Fix lockfile not being updated for 6.0.0-rc.3

* Start splitting apart reconciler, with tests

* Reify children in reify

* Baseline hydrate implementation

* Remove debug print

* Scaffold out diff implementation, just supporting name changes

* invariant -> error in decodeValue

* Flesh out diff and add getProperty

* Clear out top-level reconciler interface, start updating code that touches it

* Address review feedback

* Add (experimental) Selene configuration

* Add emptiness checks to PatchSet, remove unimplement invert method

* Improve descendant destruction behavior in InstanceMap

* Track instanceId on all reify errors

* Base implementation of applyPatch, returning partial patches on failure

* Change reify to accept InstanceMap and insert instances into it

* Start testing applyPatch for removals

* Add test for applyPatch adding instances successfully and not

* Add , which is just error with formatting

* Correctly use new diff and applyPatch APIs

* Improve applyPatch logging and fix field name typo

* Better debug output when reify fails

* Print out unapplied patch in debug mode

* Don't write properties if their values are not different.

This was exposed trying to sync the Rojo plugin, which
has a gigantic ModuleScript in it with the reflection
database. This workaround was present in some form in
many versions of Rojo, and I guess we still need it.

This time, I actually documented why it's here so that
I don't forget for the umpteenth time...

* Add placeholder test that needs to happen still

* Introduce easier plugin testing, write applyPatch properties test

* Delete legacy get/setCanonicalProperty files

* Fix trying to remove numbers instead of instances

* Change applyPatch to return partial patches instead of binary success

* Work towards being able to decode and apply refs

* Add helpers for PatchSet assertions

* Apply refs in reify, test all cases

* Improve diagnostics when patches fail to apply

* Stop logging when destroying untracked instances, it's ok

* Remove read before setting property in applyPatch

* Fix diff thinking all properties are changed

.github/workflows/ci.yml

@@ -1,6 +1,13 @@
 name: CI
 
-on: [push]
+on:
+  push:
+    branches:
+    - master
+
+  pull_request:
+    branches:
+    - master
 
 jobs:
   build:
@@ -9,10 +16,12 @@ jobs:
 
     strategy:
       matrix:
-        rust_version: [stable, "1.36.0"]
+        rust_version: [stable, "1.43.1"]
 
     steps:
     - uses: actions/checkout@v1
+      with:
+        submodules: true
 
     - name: Setup Rust toolchain
       run: rustup default ${{ matrix.rust_version }}
@@ -27,10 +36,4 @@ jobs:
       run: |
         cargo fmt -- --check
         cargo clippy
-      if: matrix.rust_version == 'stable'
-
-    - name: Build (All Features)
-      run: cargo build --locked --verbose --all-features
-
-    - name: Run tests (All Features)
-      run: cargo test --locked --verbose --all-features
+      if: matrix.rust_version == 'stable'

.github/workflows/release.yml

@@ -10,6 +10,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v1
+      with:
+        submodules: true
 
     - name: Build release binary
       run: cargo build --verbose --locked --release
@@ -25,6 +27,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v1
+      with:
+        submodules: true
 
     - name: Install Rust
       run: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
@@ -47,6 +51,8 @@ jobs:
 
     steps:
     - uses: actions/checkout@v1
+      with:
+        submodules: true
 
     - name: Build
       run: cargo build --locked --verbose --release

.gitignore

@@ -10,9 +10,15 @@
 /*.rbxl
 /*.rbxlx
 
+# Test places for the Roblox Studio Plugin
+/plugin/*.rbxlx
+
 # Roblox Studio holds 'lock' files on places
 *.rbxl.lock
 *.rbxlx.lock
 
 # Snapshot files from the 'insta' Rust crate
-**/*.snap.new
+**/*.snap.new
+
+# Selene generates a roblox.toml file that should not be checked in.
+/roblox.toml

.gitmodules

@@ -9,7 +9,4 @@
 	url = https://github.com/LPGhatguy/roblox-lua-promise.git
 [submodule "plugin/modules/t"]
 	path = plugin/modules/t
-	url = https://github.com/osyrisrblx/t.git
-[submodule "plugin/modules/rbx-dom"]
-	path = plugin/modules/rbx-dom
-	url = http://github.com/rojo-rbx/rbx-dom
+	url = https://github.com/osyrisrblx/t.git

.luacheckrc

@@ -33,7 +33,7 @@ stds.plugin = {
 stds.testez = {
 	read_globals = {
 		"describe",
-		"it", "itFOCUS", "itSKIP",
+		"it", "itFOCUS", "itSKIP", "itFIXME",
 		"FOCUS", "SKIP", "HACK_NO_XPCALL",
 		"expect",
 	}

CHANGELOG.md

@@ -2,6 +2,57 @@
 
 ## Unreleased Changes
 
+## [6.0.0 Release Candidate 3](https://github.com/rojo-rbx/rojo/releases/tag/v6.0.0-rc.3) (November 19, 2020)
+* Fixed the Rojo plugin attempted to write the non-scriptable properties `Instance.SourceAssetId` and `HttpServer.HttpEnabled`.
+* Fixed the Rojo plugin's handling of null referents.
+
+## [6.0.0 Release Candidate 2](https://github.com/rojo-rbx/rojo/releases/tag/v6.0.0-rc.2) (November 19, 2020)
+* Fixed crash when malformed CSV files are put into a project. ([#310](https://github.com/rojo-rbx/rojo/issues/310))
+* Fixed incorrect string escaping when producing Lua code from JSON files. ([#314](https://github.com/rojo-rbx/rojo/issues/314))
+* Fixed performance issues introduced in Rojo 6.0.0-rc.1. ([#317](https://github.com/rojo-rbx/rojo/issues/317))
+* Fixed `rojo plugin install` subcommand failing for everyone except Rojo developers. ([#320](https://github.com/rojo-rbx/rojo/issues/320))
+* Updated default place template to take advantage of [#210](https://github.com/rojo-rbx/rojo/pull/210).
+* Enabled glob ignore patterns by default and removed the `unstable_glob_ignore` feature.
+    * `globIgnorePaths` can be set on a project to a list of globs to ignore.
+* The Rojo plugin now completes as much as it can from a patch without disconnecting. Warnings are shown in the console.
+* Fixed 6.0.0-rc.1 regression causing instances that changed ClassName to instead... not change ClassName.
+
+## [6.0.0 Release Candidate 1](https://github.com/rojo-rbx/rojo/releases/tag/v6.0.0-rc.1) (March 29, 2020)
+This release jumped from 0.6.0 to 6.0.0. Rojo has been in use in production for many users for quite a long times, and so 6.0 is a more accurate reflection of Rojo's version than a pre-1.0 version.
+
+* Added basic settings panel to plugin, with two settings:
+    * "Open Scripts Externally": When enabled, opening a script in Studio will instead open it in your default text editor.
+    * "Two-Way Sync": When enabled, Rojo will attempt to save changes to your place back to the filesystem. **Very early feature, very broken, beware!**
+* Added `--color` option to force-enable or force-disable color in Rojo's output.
+* Added support for turning `.json` files into `ModuleScript` instances ([#308](https://github.com/rojo-rbx/rojo/pull/308))
+* Added `rojo plugin install` and `rojo plugin uninstall` to allow Rojo to manage its Roblox Studio plugin. ([#304](https://github.com/rojo-rbx/rojo/pull/304))
+* Class names no longer need to be specified for Roblox services in Rojo projects. ([#210](https://github.com/rojo-rbx/rojo/pull/210))
+* The server half of **experimental** two-way sync is now enabled by default.
+* Increased default logging verbosity in commands like `rojo build`.
+* Rojo now requires a project file again, just like 0.5.4.
+
+## [0.6.0 Alpha 3](https://github.com/rojo-rbx/rojo/releases/tag/v0.6.0-alpha.3) (March 13, 2020)
+* Added `--watch` argument to `rojo build`. ([#284](https://github.com/rojo-rbx/rojo/pull/284))
+* Added dark theme support to plugin. ([#241](https://github.com/rojo-rbx/rojo/issues/241))
+* Added a revamped `rojo init` command, which will now create more complete projects.
+* Added the `rojo doc` command, which opens Rojo's documentation in your browser.
+* Fixed many crashes from malformed projects and filesystem edge cases in `rojo serve`.
+* Simplified filesystem access code dramatically.
+* Improved error reporting and logging across the board.
+    * Log messages have a less noisy prefix.
+    * Any thread panicking now causes Rojo to abort instead of existing as a zombie.
+    * Errors now have a list of causes, helping make many errors more clear.
+
+## [0.6.0 Alpha 2](https://github.com/rojo-rbx/rojo/releases/tag/v0.6.0-alpha.2) (March 6, 2020)
+* Fixed `rojo upload` command always uploading models.
+* Removed `--kind` parameter to `rojo upload`; Rojo now automatically uploads the correct kind of asset based on your project file.
+
+## [0.5.4](https://github.com/rojo-rbx/rojo/releases/tag/v0.5.4) (February 26, 2020)
+This is a general maintenance release for the Rojo 0.5.x release series.
+
+* Updated reflection database and other dependencies.
+* First stable release with binaries for macOS and Linux.
+
 ## [0.6.0 Alpha 1](https://github.com/rojo-rbx/rojo/releases/tag/v0.6.0-alpha.1) (January 22, 2020)
 
 ### General
@@ -26,6 +77,12 @@
 * Added "error" state to show errors in a place that isn't the output panel.
 * Improved diagnostics for when the Rojo plugin cannot create an instance.
 
+## [0.5.3](https://github.com/rojo-rbx/rojo/releases/tag/v0.5.3) (October 15, 2019)
+* Fixed an issue where Rojo would throw an error when encountering recently-added instance classes.
+
+## [0.5.2](https://github.com/rojo-rbx/rojo/releases/tag/v0.5.2) (October 14, 2019)
+* Fixed an issue where `LocalizationTable` instances would have their column order randomized. ([#173](https://github.com/rojo-rbx/rojo/issues/173))
+
 ## [0.5.1](https://github.com/rojo-rbx/rojo/releases/tag/v0.5.1) (October 4, 2019)
 * Fixed an issue where Rojo would drop changes if they happened too quickly ([#252](https://github.com/rojo-rbx/rojo/issues/252))
 * Improved diagnostics for when the Rojo plugin cannot create an instance.
@@ -80,7 +137,7 @@
 
 ## [0.5.0 Alpha 9](https://github.com/rojo-rbx/rojo/releases/tag/v0.5.0-alpha.9) (April 4, 2019)
 * Changed `rojo build` to use buffered I/O, which can make it up to 2x faster in some cases.
-    * Building [*Road Not Taken*](https://github.com/rojo-rbx/roads) to an `rbxlx` file dropped from 150ms to 70ms on my machine
+    * Building [*Road Not Taken*](https://github.com/LPGhatguy/roads) to an `rbxlx` file dropped from 150ms to 70ms on my machine
 * Fixed `LocalizationTable` instances being made from `csv` files incorrectly interpreting empty rows and columns. ([#149](https://github.com/rojo-rbx/rojo/pull/149))
 * Fixed CSV files with entries that parse as numbers causing Rojo to panic. ([#152](https://github.com/rojo-rbx/rojo/pull/152))
 * Improved error messages when malformed CSV files are found in a Rojo project.
@@ -277,4 +334,4 @@
 * More robust syncing with a new reconciler
 
 ## [0.1.0](https://github.com/rojo-rbx/rojo/releases/tag/v0.1.0) (November 29, 2017)
-* Initial release, functionally very similar to [rbxfs](https://github.com/rojo-rbx/rbxfs)
+* Initial release, functionally very similar to [rbxfs](https://github.com/LPGhatguy/rbxfs)

CONTRIBUTING.md

@@ -1,5 +1,5 @@
 # Contributing to the Rojo Project
-Rojo is a big project and can always use more help! This guide covers all repositories underneath the [rojo-rbx organization on GitHub](https://github.com/rojo-rbx).
+Rojo is a big project and can always use more help!
 
 Some of the repositories covered are:
 
@@ -15,8 +15,7 @@ You'll want these tools to work on Rojo:
 
 * Latest stable Rust compiler
 * Latest stable [Rojo](https://github.com/rojo-rbx/rojo)
-* Latest stable [Remodel](https://github.com/rojo-rbx/remodel)
-* Latest stable [run-in-roblox](https://github.com/rojo-rbx/run-in-roblox)
+* [Foreman](https://github.com/Roblox/foreman)
 
 ## Documentation
 Documentation impacts way more people than the individual lines of code we write.
@@ -33,15 +32,13 @@ Please file issues and we'll try to help figure out what the best way forward is
 ## Pushing a Rojo Release
 The Rojo release process is pretty manual right now. If you need to do it, here's how:
 
-1. Bump server version in [`server/Cargo.toml`](server/Cargo.toml)
+1. Bump server version in [`Cargo.toml`](Cargo.toml)
 2. Bump plugin version in [`plugin/src/Config.lua`](plugin/src/Config.lua)
 3. Run `cargo test` to update `Cargo.lock` and double-check tests
 4. Update [`CHANGELOG.md`](CHANGELOG.md)
 5. Commit!
     * `git add . && git commit -m "Release vX.Y.Z"`
 6. Tag the commit with the version from `Cargo.toml` prepended with a v, like `v0.4.13`
-7. Build Windows release build of CLI
-    * `cargo build --release`
 7. Publish the CLI
     * `cargo publish`
 8. Build and upload the plugin
@@ -52,4 +49,5 @@ The Rojo release process is pretty manual right now. If you need to do it, here'
 10. Copy GitHub release content from previous release
     * Update the leading text with a summary about the release
     * Paste the changelog notes (as-is!) from [`CHANGELOG.md`](CHANGELOG.md)
-    * Write a small summary of each major feature
+    * Write a small summary of each major feature
+    * Attach release artifacts from GitHub Actions for each platform

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rojo"
-version = "0.6.0-alpha.1"
+version = "6.0.0-rc.3"
 authors = ["Lucien Greathouse <me@lpghatguy.com>"]
 description = "Enables professional-grade development tools for Roblox developers"
 license = "MPL-2.0"
@@ -11,33 +11,32 @@ readme = "README.md"
 edition = "2018"
 
 exclude = [
-    "/plugin/**",
     "/test-projects/**",
 ]
 
+[profile.dev]
+panic = "abort"
+
+[profile.release]
+panic = "abort"
+
 [features]
 default = []
 
-# Turn on support for specifying glob ignore path rules in the project format.
-unstable_glob_ignore_paths = []
-
-# Turn on the server half of Rojo's unstable two-way sync feature.
-unstable_two_way_sync = []
-
 # Enable this feature to live-reload assets from the web UI.
 dev_live_assets = []
 
 [workspace]
 members = [
-    "rojo-test",
     "rojo-insta-ext",
     "clibrojo",
+    "memofs",
 ]
 
 default-members = [
     ".",
-    "rojo-test",
     "rojo-insta-ext",
+    "memofs",
 ]
 
 [lib]
@@ -53,9 +52,15 @@ name = "build"
 harness = false
 
 [dependencies]
+memofs = { version = "0.1.2", path = "memofs" }
+
+anyhow = "1.0.27"
+backtrace = "0.3"
+bincode = "1.2.1"
 crossbeam-channel = "0.4.0"
 csv = "1.1.1"
 env_logger = "0.7.1"
+fs-err = "2.2.0"
 futures = "0.1.29"
 globset = "0.4.4"
 humantime = "1.3.0"
@@ -65,6 +70,7 @@ lazy_static = "1.4.0"
 log = "0.4.8"
 maplit = "1.0.1"
 notify = "4.0.14"
+opener = "0.4.1"
 rbx_binary = "0.5.0"
 rbx_dom_weak = "1.10.1"
 rbx_reflection = "3.3.408"
@@ -73,25 +79,34 @@ regex = "1.3.1"
 reqwest = "0.9.20"
 ritz = "0.1.0"
 rlua = "0.17.0"
+roblox_install = "0.2.2"
 serde = { version = "1.0", features = ["derive", "rc"] }
 serde_json = "1.0"
-snafu = "0.6.0"
 structopt = "0.3.5"
 termcolor = "1.0.5"
+thiserror = "1.0.11"
+tokio = "0.1.22"
 uuid = { version = "0.8.1", features = ["v4", "serde"] }
 
 [target.'cfg(windows)'.dependencies]
 winreg = "0.6.2"
 
+[build-dependencies]
+memofs = { version = "0.1.3", path = "memofs" }
+
+anyhow = "1.0.27"
+bincode = "1.2.1"
+fs-err = "2.3.0"
+maplit = "1.0.1"
+
 [dev-dependencies]
 rojo-insta-ext = { path = "rojo-insta-ext" }
 
 criterion = "0.3"
-insta = { version = "0.12.0", features = ["redactions"] }
+insta = { version = "0.13.1", features = ["redactions"] }
 lazy_static = "1.2"
 paste = "0.1"
 pretty_assertions = "0.6.1"
 serde_yaml = "0.8.9"
 tempfile = "3.0"
-tokio = "0.1.22"
 walkdir = "2.1"

README.md

@@ -13,8 +13,8 @@
     <a href="https://crates.io/crates/rojo">
         <img src="https://img.shields.io/crates/v/rojo.svg?label=latest%20release" alt="Latest server version" />
     </a>
-    <a href="https://rojo.space/docs/0.5.x">
-        <img src="https://img.shields.io/badge/docs-0.5.x-brightgreen.svg" alt="Rojo 0.5.x Documentation" />
+    <a href="https://rojo.space/docs">
+        <img src="https://img.shields.io/badge/docs-website-brightgreen.svg" alt="Rojo Documentation" />
     </a>
 </div>
 
@@ -34,22 +34,21 @@ Rojo enables:
 * Streaming `rbxmx` and `rbxm` models into your game in real time
 * Packaging and deploying your project to Roblox.com from the command line
 
-Soon, Rojo will be able to:
+In the future, Rojo will be able to:
 
-* Automatically convert your existing game to work with Rojo
 * Sync instances from Roblox Studio to the filesystem
-* Automatically manage your assets on Roblox.com, like images and sounds
+* Automatically convert your existing game to work with Rojo
 * Import custom instances like MoonScript code
 
 ## [Documentation](https://rojo.space/docs)
-If you find any mistakes, feel free to make changes in the [docs](https://github.com/rojo-rbx/rojo/tree/master/docs) folder of this repository and submit a pull request!
+Documentation is hosted in the [rojo.space repository](https://github.com/rojo-rbx/rojo.space).
 
 ## Contributing
 Check out our [contribution guide](CONTRIBUTING.md) for detailed instructions for helping work on Rojo!
 
 Pull requests are welcome!
 
-Rojo supports Rust 1.36.0 and newer. The minimum supported version of Rust is based on the latest versions of the dependencies that Rojo has.
+Rojo supports Rust 1.43.1 and newer. The minimum supported version of Rust is based on the latest versions of the dependencies that Rojo has.
 
 ## License
 Rojo is available under the terms of the Mozilla Public License, Version 2.0. See [LICENSE.txt](LICENSE.txt) for details.

assets/default-model-project/README.md

@@ -0,0 +1,11 @@
+# {project_name}
+Generated by [Rojo](https://github.com/rojo-rbx/rojo) {rojo_version}.
+
+## Getting Started
+To build this library or plugin, use:
+
+```bash
+rojo build -o "{project_name}.rbxmx"
+```
+
+For more help, check out [the Rojo documentation](https://rojo.space/docs).

assets/default-model-project/default.project.json

@@ -0,0 +1,6 @@
+{
+  "name": "{project_name}",
+  "tree": {
+    "$path": "src"
+  }
+}

assets/default-model-project/gitignore.txt

@@ -0,0 +1,3 @@
+# Roblox Studio lock files
+/*.rbxlx.lock
+/*.rbxl.lock

assets/default-model-project/src-init.lua

@@ -0,0 +1,5 @@
+return {
+	hello = function()
+		print("Hello world, from {project_name}!")
+	end,
+}

assets/default-place-project/README.md

@@ -0,0 +1,17 @@
+# {project_name}
+Generated by [Rojo](https://github.com/rojo-rbx/rojo) {rojo_version}.
+
+## Getting Started
+To build the place from scratch, use:
+
+```bash
+rojo build -o "{project_name}.rbxlx"
+```
+
+Next, open `{project_name}.rbxlx` in Roblox Studio and start the Rojo server:
+
+```bash
+rojo serve
+```
+
+For more help, check out [the Rojo documentation](https://rojo.space/docs).

assets/default-place-project/default.project.json

@@ -1,41 +1,29 @@
 {
-  "name": "[placeholder]",
+  "name": "{project_name}",
   "tree": {
     "$className": "DataModel",
-    "HttpService": {
-      "$className": "HttpService",
-      "$properties": {
-        "HttpEnabled": true
-      }
-    },
-    "Lighting": {
-      "$className": "Lighting",
-      "$properties": {
-        "Ambient": [
-          0,
-          0,
-          0
-        ],
-        "Brightness": 2,
-        "GlobalShadows": true,
-        "Outlines": false,
-        "Technology": "Voxel"
-      }
-    },
+
     "ReplicatedStorage": {
-      "$className": "ReplicatedStorage",
-      "Source": {
-        "$path": "src"
+      "Common": {
+        "$path": "src/shared"
       }
     },
-    "SoundService": {
-      "$className": "SoundService",
-      "$properties": {
-        "RespectFilteringEnabled": true
+
+    "ServerScriptService": {
+      "Server": {
+        "$path": "src/server"
       }
     },
+
+    "StarterPlayer": {
+      "StarterPlayerScripts": {
+        "Client": {
+          "$path": "src/client"
+        }
+      }
+    },
+
     "Workspace": {
-      "$className": "Workspace",
       "$properties": {
         "FilteringEnabled": true
       },
@@ -61,6 +49,24 @@
           ]
         }
       }
+    },
+    "Lighting": {
+      "$properties": {
+        "Ambient": [
+          0,
+          0,
+          0
+        ],
+        "Brightness": 2,
+        "GlobalShadows": true,
+        "Outlines": false,
+        "Technology": "Voxel"
+      }
+    },
+    "SoundService": {
+      "$properties": {
+        "RespectFilteringEnabled": true
+      }
     }
   }
 }

assets/default-place-project/gitignore.txt

@@ -0,0 +1,6 @@
+# Project place file
+/{project_name}.rbxlx
+
+# Roblox Studio lock files
+/*.rbxlx.lock
+/*.rbxl.lock

benches/build.rs

@@ -35,6 +35,7 @@ fn place_setup<P: AsRef<Path>>(input_path: P) -> (TempDir, BuildCommand) {
 
     let options = BuildCommand {
         project: input,
+        watch: false,
         output,
     };
 

build.rs

@@ -0,0 +1,74 @@
+use std::{
+    env, io,
+    path::{Path, PathBuf},
+};
+
+use fs_err as fs;
+use fs_err::File;
+use maplit::hashmap;
+use memofs::VfsSnapshot;
+
+fn snapshot_from_fs_path(path: &Path) -> io::Result<VfsSnapshot> {
+    println!("cargo:rerun-if-changed={}", path.display());
+
+    if path.is_dir() {
+        let mut children = Vec::new();
+
+        for entry in fs::read_dir(path)? {
+            let entry = entry?;
+
+            let file_name = entry.file_name().to_str().unwrap().to_owned();
+
+            // We can skip any TestEZ test files since they aren't necessary for
+            // the plugin to run.
+            if file_name.ends_with(".spec.lua") {
+                continue;
+            }
+
+            let child_snapshot = snapshot_from_fs_path(&entry.path())?;
+            children.push((file_name, child_snapshot));
+        }
+
+        Ok(VfsSnapshot::dir(children))
+    } else {
+        let content = fs::read_to_string(path)?;
+
+        Ok(VfsSnapshot::file(content))
+    }
+}
+
+fn main() -> Result<(), anyhow::Error> {
+    let out_dir = env::var_os("OUT_DIR").unwrap();
+
+    let root_dir = env::var_os("CARGO_MANIFEST_DIR").unwrap();
+    let plugin_root = PathBuf::from(root_dir).join("plugin");
+
+    let plugin_modules = plugin_root.join("modules");
+
+    let snapshot = VfsSnapshot::dir(hashmap! {
+        "default.project.json" => snapshot_from_fs_path(&plugin_root.join("default.project.json"))?,
+        "fmt" => snapshot_from_fs_path(&plugin_root.join("fmt"))?,
+        "http" => snapshot_from_fs_path(&plugin_root.join("http"))?,
+        "log" => snapshot_from_fs_path(&plugin_root.join("log"))?,
+        "rbx_dom_lua" => snapshot_from_fs_path(&plugin_root.join("rbx_dom_lua"))?,
+        "src" => snapshot_from_fs_path(&plugin_root.join("src"))?,
+        "modules" => VfsSnapshot::dir(hashmap! {
+            "roact" => VfsSnapshot::dir(hashmap! {
+                "src" => snapshot_from_fs_path(&plugin_modules.join("roact").join("src"))?
+            }),
+            "promise" => VfsSnapshot::dir(hashmap! {
+                "lib" => snapshot_from_fs_path(&plugin_modules.join("promise").join("lib"))?
+            }),
+            "t" => VfsSnapshot::dir(hashmap! {
+                "lib" => snapshot_from_fs_path(&plugin_modules.join("t").join("lib"))?
+            }),
+        }),
+    });
+
+    let out_path = Path::new(&out_dir).join("plugin.bincode");
+    let out_file = File::create(&out_path)?;
+
+    bincode::serialize_into(out_file, &snapshot)?;
+
+    Ok(())
+}

design.gv

@@ -1,30 +0,0 @@
-digraph Rojo {
-	concentrate = true;
-	node [fontname = "sans-serif"];
-
-	plugin [label="Roblox Studio Plugin"]
-	session [label="Session"]
-	rbx_tree [label="Instance Tree"]
-	imfs [label="In-Memory Filesystem"]
-	fs_impl [label="Filesystem Implementation\n(stubbed in tests)"]
-	fs [label="Real Filesystem"]
-	snapshot_subsystem [label="Snapshot Subsystem\n(reconciler)"]
-	snapshot_generator [label="Snapshot Generator"]
-	user_middleware [label="User Middleware\n(MoonScript, etc.)"]
-	builtin_middleware [label="Built-in Middleware\n(.lua, .rbxm, etc.)"]
-	api [label="Web API"]
-	file_watcher [label="File Watcher"]
-
-	session -> imfs
-	session -> rbx_tree
-	session -> snapshot_subsystem
-	session -> snapshot_generator
-	session -> file_watcher [dir="both"]
-	file_watcher -> imfs
-	snapshot_generator -> user_middleware
-	snapshot_generator -> builtin_middleware
-	plugin -> api [style="dotted"; dir="both"; minlen=2]
-	api -> session
-	imfs -> fs_impl
-	fs_impl -> fs
-}

docs/extra.css

@@ -1,13 +0,0 @@
-.md-typeset__table {
-  width: 100%;
-}
-
-.feature-image img {
-  border: 1px solid rgba(0, 0, 0, 0.2);
-  box-shadow: 1px 1px 4px rgba(0, 0, 0, 0.2);
-}
-
-.codehilite {
-  border: 1px solid rgba(0, 0, 0, 0.2);
-  box-shadow: 1px 1px 4px rgba(0, 0, 0, 0.2);
-}

docs/guide/existing-game.md

@@ -1,11 +0,0 @@
-**This page is under construction!**
-
-## Summary
-* Tools to port existing games are in progress!
-    * [rbxlx-to-rojo](https://github.com/rojo-rbx/rbxlx-to-rojo)
-    * `rojo export` ([issue #208](https://github.com/rojo-rbx/rojo/issues/208))
-* Can port as much or as little of your game as you like
-    * Rojo can manage just a slice of your game!
-* Some Roblox idioms aren't very well supported
-    * Redundant copies of scripts don't work well with files
-    * Having only a couple places with scripts simplifies your project dramatically!

docs/guide/installation.md

@@ -1,48 +0,0 @@
-This is this installation guide for Rojo **0.5.x**.
-
-[TOC]
-
-## Overview
-Rojo has two components:
-
-* The command line interface (CLI)
-* The Roblox Studio plugin
-
-!!! info
-    It's important that your installed version of the plugin and CLI are compatible.
-
-    The plugin will show errors in the Roblox Studio output window if there is a version mismatch.
-
-## Visual Studio Code Extension
-If you use Visual Studio Code, you can install [the Rojo VS Code extension](https://marketplace.visualstudio.com/items?itemName=evaera.vscode-rojo), which will install both halves of Rojo for you. It even has a nifty UI to sync files and start/stop the Rojo server!
-
-## Installing the CLI
-
-### Installing from GitHub
-If you're on Windows, there are pre-built binaries available from Rojo's [GitHub Releases page](https://github.com/LPGhatguy/rojo/releases).
-
-The Rojo CLI must be run from the command line, like Terminal.app on MacOS or `cmd.exe` on Windows. It's recommended that you put the Rojo CLI executable on your `PATH` to make this easier.
-
-### Installing from Cargo
-If you have Rust installed, the easiest way to get Rojo is with Cargo!
-
-To install the latest 0.5.x release, use:
-
-```sh
-cargo install rojo
-```
-
-If you're upgrading from a previous version of Rojo, you may need to pass `--force` to tell Cargo to overwrite your existing version.
-
-## Installing the Plugin
-
-### Installing from GitHub
-The Rojo Roblox Studio plugin is available from Rojo's [GitHub Releases page](https://github.com/LPGhatguy/rojo/releases).
-
-Download the attached `rbxm` file and put it into your Roblox Studio plugins folder. You can find that folder by pressing **Plugins Folder** from your Plugins toolbar in Roblox Studio:
-
-!['Plugins Folder' button in Roblox Studio](../images/plugins-folder-in-studio.png)
-{: align="center" }
-
-### Installing from Roblox.com
-Visit [Rojo's Roblox.com Plugin page](https://www.roblox.com/library/1997686364) in Roblox Studio and press **Install**.

docs/guide/migrating-to-epiphany.md

@@ -1,63 +0,0 @@
-Rojo underwent a large refactor during most of 2018 to enable a bunch of new features and lay groundwork for lots more in 2019. As such, Rojo **0.5.x** projects are not compatible with Rojo **0.4.x** projects.
-
-[TOC]
-
-## Supporting Both 0.4.x and 0.5.x
-Rojo 0.5.x uses a different name for its project format. While 0.4.x used `rojo.json`, 0.5.x uses `default.project.json`, which allows them to coexist.
-
-If you aren't sure about upgrading or want to upgrade gradually, it's possible to keep both files in the same project without causing problems.
-
-## Upgrading Your Project File
-Project files in 0.5.x are more explicit and flexible than they were in 0.4.x. Project files can now describe models and plugins in addition to places.
-
-This new project file format also guards against two of the biggest pitfalls when writing a config file:
-
-* Using a service as a partition target directly, which often wiped away extra instances
-* Defining two partitions that overlapped, which made Rojo act unpredictably
-
-The biggest change is that the `partitions` field has been replaced with a new field, `tree`, that describes the entire hierarchy of your project from the top-down.
-
-A project for 0.4.x that syncs from the `src` directory into `ReplicatedStorage.Source` would look like this:
-
-```json
-{
-    "name": "Rojo 0.4.x Example",
-    "partitions": {
-        "path": "src",
-        "target": "ReplicatedStorage.Source"
-    }
-}
-```
-
-In 0.5.x, the project format is more explicit:
-
-```json
-{
-    "name": "Rojo 0.5.x Example",
-    "tree": {
-        "$className": "DataModel",
-        "ReplicatedStorage": {
-            "$className": "ReplicatedStorage",
-            "Source": {
-                "$path": "src"
-            }
-        }
-    }
-}
-```
-
-For each object in the tree, we define *metadata* and *children*.
-
-Metadata begins with a dollar sign (`$`), like `$className`. This is so that children and metadata can coexist without creating too many nested layers.
-
-All other values are considered children, where the key is the instance's name, and the value is an object, repeating the process.
-
-## Migrating Unknown Files
-If you used Rojo to sync in files as `StringValue` objects, you'll need to make sure those files end with the `txt` extension to preserve this in Rojo 0.5.x.
-
-Unknown files are now ignored in Rojo instead of being converted to `StringValue` objects.
-
-## Migrating `init.model.json` files
-In Rojo 0.4.x, it's possible to create a file named `init.model.json` that lets you describe a model that becomes the container for all of the other files in the folder, just like `init.lua`.
-
-In Rojo 0.5.x, this feature has been replaced with `init.meta.json` files. See [Sync Details](../../reference/sync-details) for more information about these new files.

docs/guide/new-game.md

@@ -1,90 +0,0 @@
-[TOC]
-
-## Creating the Rojo Project
-To use Rojo to build a game, you'll need to create a new project file, which tells Rojo how to turn your files into a Roblox place.
-
-First, create a new folder to contain the files for your game and open up a new terminal inside of it, like cmd.exe or Bash.
-
-It's convenient to make the folder from the command line:
-
-```sh
-mkdir my-new-project
-cd my-new-project
-```
-
-Inside the folder, initialize a new Rojo project:
-
-```sh
-rojo init
-```
-
-Rojo will make a small project file in your directory, named `default.project.json`. It matches the "Baseplate" template from Roblox Studio, except that it'll take any files you put in a folder called `src` and put it into `ReplicatedStorage.Source`.
-
-Speaking of files, make sure to create a directory named `src` in this folder, or Rojo will be upset about missing files!
-
-```sh
-mkdir src
-```
-
-Let's also add a Lua file, `hello.lua` to the `src` folder, so that we can make this project our own.
-
-```sh
-echo 'return "Hello, Rojo!"' > src/hello.lua
-```
-
-## Building Your Place
-Now that we have a project, one thing we can do is build a Roblox place file for our project. This is a great way to get started with a project quickly with no fuss.
-
-All we have to do is call `rojo build`:
-
-```sh
-rojo build -o MyNewProject.rbxlx
-```
-
-If you open `MyNewProject.rbxlx` in Roblox Studio now, you should see a `Folder` named "Source" containing a `ModuleScript` under `ReplicatedStorage`.
-
-!!! info
-    To generate a binary place file instead, use `rbxl`. Note that support for binary model/place files (`rbxm` and `rbxl`) is very limited in Rojo presently.
-
-## Live-Syncing into Studio
-Building a place file is great for starting to work on a game, but for active iteration, you'll want something faster.
-
-In Roblox Studio, make sure the Rojo plugin is installed. If you need it, check out [the installation guide](../installation) to learn how to install it.
-
-To expose your project to the plugin, you'll need to start a new **live sync session** from the command line:
-
-```sh
-rojo serve
-```
-
-You should see output like this in your terminal:
-
-```sh
-$ rojo serve
-Rojo server listening on port 34872
-```
-
-Switch into Roblox Studio and press the **Connect** button on the Rojo plugin toolbar. A dialog should appear:
-
-![Rojo plugin connection dialog](../images/connection-dialog.png)
-{: class="feature-image" align="center" }
-
-If the port number doesn't match the output from the command line, change it, and then press **Connect**.
-
-If all went well, you should now be able to change files in the `src` directory and watch them sync into Roblox Studio in real time!
-
-## Uploading Your Place
-Aimed at teams that want serious levels of automation, Rojo can upload places to Roblox.com automatically.
-
-You'll need an existing game on Roblox.com as well as the `.ROBLOSECURITY` cookie of an account that has write access to that game.
-
-!!! warning
-    It's recommended that you set up a Roblox account dedicated to deploying your game instead of your personal account in case your security cookie is compromised.
-
-Generating and publishing your game is as simple as:
-
-```sh
-rojo upload --asset_id [PLACE ID] --cookie "[SECURITY COOKIE]"
-```
-
-An example project is available on GitHub that deploys to roblox.com from GitHub and Travis-CI automatically: [https://github.com/LPGhatguy/roads](https://github.com/LPGhatguy/roads)

docs/help.md

@@ -1,7 +0,0 @@
-Rojo is a fairly complex tool to adopt, but there's a community willing to help!
-
-The [Roblox Open Source Community Discord](https://discord.gg/wH5ncNS) currently hosts a Rojo support channel, **#rojo**, that is a great place to get help as problems come up.
-
-If you find anything that looks like a bug or have ideas for how to improve Rojo, feel free to file an issue on [Rojo's GitHub issue tracker](https://github.com/rojo-rbx/rojo/issues).
-
-Rojo's primary maintainer is also available on Twitter, [@LPGhatguy](https://twitter.com/LPGhatguy).

docs/images/sync-example-files.gv

@@ -1,17 +0,0 @@
-digraph "Sync Files" {
-	graph [
-	    ranksep = "0.7",
-	    nodesep = "0.5",
-	];
-	node [
-	    fontname = "monospace",
-	    shape = "record",
-	];
-
-	my_model [label = "MyModel"]
-	init_server [label = "init.server.lua"]
-	foo [label = "foo.lua"]
-
-	my_model -> init_server
-	my_model -> foo
-}

docs/images/sync-example-files.svg

@@ -1,38 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
- "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<!-- Generated by graphviz version 2.38.0 (20140413.2041)
- -->
-<!-- Title: Sync Files Pages: 1 -->
-<svg width="258pt" height="132pt"
- viewBox="0.00 0.00 258.00 132.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
-<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 128)">
-<title>Sync Files</title>
-<polygon fill="white" stroke="none" points="-4,4 -4,-128 254,-128 254,4 -4,4"/>
-<!-- my_model -->
-<g id="node1" class="node"><title>my_model</title>
-<polygon fill="none" stroke="black" points="104,-87.5 104,-123.5 178,-123.5 178,-87.5 104,-87.5"/>
-<text text-anchor="middle" x="141" y="-101.8" font-family="monospace" font-size="14.00">MyModel</text>
-</g>
-<!-- init_server -->
-<g id="node2" class="node"><title>init_server</title>
-<polygon fill="none" stroke="black" points="0,-0.5 0,-36.5 140,-36.5 140,-0.5 0,-0.5"/>
-<text text-anchor="middle" x="70" y="-14.8" font-family="monospace" font-size="14.00">init.server.lua</text>
-</g>
-<!-- my_model&#45;&gt;init_server -->
-<g id="edge1" class="edge"><title>my_model&#45;&gt;init_server</title>
-<path fill="none" stroke="black" d="M126.632,-87.299C116.335,-74.9713 102.308,-58.1787 90.7907,-44.3902"/>
-<polygon fill="black" stroke="black" points="93.4435,-42.1065 84.3465,-36.6754 88.0711,-46.594 93.4435,-42.1065"/>
-</g>
-<!-- foo -->
-<g id="node3" class="node"><title>foo</title>
-<polygon fill="none" stroke="black" points="176,-0.5 176,-36.5 250,-36.5 250,-0.5 176,-0.5"/>
-<text text-anchor="middle" x="213" y="-14.8" font-family="monospace" font-size="14.00">foo.lua</text>
-</g>
-<!-- my_model&#45;&gt;foo -->
-<g id="edge2" class="edge"><title>my_model&#45;&gt;foo</title>
-<path fill="none" stroke="black" d="M155.57,-87.299C166.013,-74.9713 180.237,-58.1787 191.917,-44.3902"/>
-<polygon fill="black" stroke="black" points="194.659,-46.5681 198.451,-36.6754 189.317,-42.0437 194.659,-46.5681"/>
-</g>
-</g>
-</svg>

docs/images/sync-example-instances.gv

@@ -1,15 +0,0 @@
-digraph "Sync Files" {
-	graph [
-	    ranksep = "0.7",
-	    nodesep = "0.5",
-	];
-	node [
-	    fontname = "monospace",
-	    shape = "record",
-	];
-
-	my_model [label = "MyModel (Script)"]
-	foo [label = "foo (ModuleScript)"]
-
-	my_model -> foo
-}

docs/images/sync-example-instances.svg

@@ -1,28 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
- "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<!-- Generated by graphviz version 2.38.0 (20140413.2041)
- -->
-<!-- Title: Sync Files Pages: 1 -->
-<svg width="173pt" height="132pt"
- viewBox="0.00 0.00 173.00 132.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
-<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 128)">
-<title>Sync Files</title>
-<polygon fill="white" stroke="none" points="-4,4 -4,-128 169,-128 169,4 -4,4"/>
-<!-- my_model -->
-<g id="node1" class="node"><title>my_model</title>
-<polygon fill="none" stroke="black" points="8,-87.5 8,-123.5 157,-123.5 157,-87.5 8,-87.5"/>
-<text text-anchor="middle" x="82.5" y="-101.8" font-family="monospace" font-size="14.00">MyModel (Script)</text>
-</g>
-<!-- foo -->
-<g id="node2" class="node"><title>foo</title>
-<polygon fill="none" stroke="black" points="0,-0.5 0,-36.5 165,-36.5 165,-0.5 0,-0.5"/>
-<text text-anchor="middle" x="82.5" y="-14.8" font-family="monospace" font-size="14.00">foo (ModuleScript)</text>
-</g>
-<!-- my_model&#45;&gt;foo -->
-<g id="edge1" class="edge"><title>my_model&#45;&gt;foo</title>
-<path fill="none" stroke="black" d="M82.5,-87.299C82.5,-75.6626 82.5,-60.0479 82.5,-46.7368"/>
-<polygon fill="black" stroke="black" points="86.0001,-46.6754 82.5,-36.6754 79.0001,-46.6755 86.0001,-46.6754"/>
-</g>
-</g>
-</svg>

docs/images/sync-example-json-model.gv

@@ -1,17 +0,0 @@
-digraph "Sync Files" {
-	graph [
-	    ranksep = "0.7",
-	    nodesep = "0.5",
-	];
-	node [
-	    fontname = "monospace",
-	    shape = "record",
-	];
-
-	model [label = "My Cool Model (Folder)"]
-	root_part [label = "RootPart (Part)"]
-	send_money [label = "SendMoney (RemoteEvent)"]
-
-	model -> root_part
-	model -> send_money
-}

docs/images/sync-example-json-model.svg

@@ -1,38 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
- "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd">
-<!-- Generated by graphviz version 2.38.0 (20140413.2041)
- -->
-<!-- Title: Sync Files Pages: 1 -->
-<svg width="390pt" height="132pt"
- viewBox="0.00 0.00 390.00 132.00" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
-<g id="graph0" class="graph" transform="scale(1 1) rotate(0) translate(4 128)">
-<title>Sync Files</title>
-<polygon fill="white" stroke="none" points="-4,4 -4,-128 386,-128 386,4 -4,4"/>
-<!-- model -->
-<g id="node1" class="node"><title>model</title>
-<polygon fill="none" stroke="black" points="75,-87.5 75,-123.5 273,-123.5 273,-87.5 75,-87.5"/>
-<text text-anchor="middle" x="174" y="-101.8" font-family="monospace" font-size="14.00">My Cool Model (Folder)</text>
-</g>
-<!-- root_part -->
-<g id="node2" class="node"><title>root_part</title>
-<polygon fill="none" stroke="black" points="0,-0.5 0,-36.5 140,-36.5 140,-0.5 0,-0.5"/>
-<text text-anchor="middle" x="70" y="-14.8" font-family="monospace" font-size="14.00">RootPart (Part)</text>
-</g>
-<!-- model&#45;&gt;root_part -->
-<g id="edge1" class="edge"><title>model&#45;&gt;root_part</title>
-<path fill="none" stroke="black" d="M152.954,-87.299C137.448,-74.6257 116.168,-57.2335 99.0438,-43.2377"/>
-<polygon fill="black" stroke="black" points="100.972,-40.2938 91.0147,-36.6754 96.5426,-45.7138 100.972,-40.2938"/>
-</g>
-<!-- send_money -->
-<g id="node3" class="node"><title>send_money</title>
-<polygon fill="none" stroke="black" points="176,-0.5 176,-36.5 382,-36.5 382,-0.5 176,-0.5"/>
-<text text-anchor="middle" x="279" y="-14.8" font-family="monospace" font-size="14.00">SendMoney (RemoteEvent)</text>
-</g>
-<!-- model&#45;&gt;send_money -->
-<g id="edge2" class="edge"><title>model&#45;&gt;send_money</title>
-<path fill="none" stroke="black" d="M195.248,-87.299C210.904,-74.6257 232.388,-57.2335 249.677,-43.2377"/>
-<polygon fill="black" stroke="black" points="252.213,-45.6878 257.783,-36.6754 247.809,-40.2471 252.213,-45.6878"/>
-</g>
-</g>
-</svg>

docs/index.md

@@ -1,18 +0,0 @@
-This is the documentation home for **the Rojo `master` branch**.
-
-!!! warning
-    Documentation here may not apply to the latest release of Rojo yet.
-
-    For documentation for the latest stable release series, 0.5.x, go to:
-
-    [https://rojo.space/docs/0.5.x](https://rojo.space/docs/0.5.x)
-
-Available versions of these docs:
-
-* [Latest version from `master` branch](https://rojo.space/docs/latest)
-* [0.5.x](https://rojo.space/docs/0.5.x)
-* [0.4.x](https://rojo.space/docs/0.4.x)
-
-**Rojo** is a tool designed to enable Roblox developers to use professional-grade software engineering tools.
-
-This documentation is a continual work in progress. If you find any issues, please file an issue on [Rojo's issue tracker](https://github.com/rojo-rbx/rojo/issues)!

docs/internals/overview.md

@@ -1,45 +0,0 @@
-This document aims to give a general overview of how Rojo works. It's intended for people who want to contribute to the project as well as anyone who's just curious how the tool works!
-
-[TOC]
-
-## CLI
-
-### RbxTree
-Rojo uses a library named [`rbx_tree`](https://github.com/LPGhatguy/rbx-tree) as its implementation of the Roblox DOM. It serves as a common format for serialization to all the formats Rojo supports!
-
-Rojo uses two related libraries to deserialize instances from Roblox's file formats, `rbx_xml` and `rbx_binary`.
-
-### In-Memory Filesystem (IMFS)
-Relevant source files:
-
-* [`server/src/imfs.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/imfs.rs)
-* [`server/src/fs_watcher.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/fs_watcher.rs)
-
-Rojo keeps an in-memory copy of all files that it needs reasons about. This enables taking fast, stateless, tear-tree snapshots of files to turn them into instances.
-
-Keeping an in-memory copy of file contents will also enable Rojo to debounce changes that are caused by Rojo itself. This'll happen when two-way sync finally happens.
-
-### Snapshot Reconciler
-Relevant source files:
-
-* [`server/src/snapshot_reconciler.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/snapshot_reconciler.rs)
-* [`server/src/rbx_snapshot.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/rbx_snapshot.rs)
-* [`server/src/rbx_session.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/rbx_session.rs)
-
-To simplify incremental updates of instances, Rojo generates lightweight snapshots describing how files map to instances. This means that Rojo can treat file change events similarly to damage painting as opposed to trying to surgically update the correct instances.
-
-This approach reduces the number of desynchronization bugs, reduces the complexity of important pieces of the codebase, and makes writing plugins a lot easier.
-
-### HTTP API
-Relevant source files:
-
-* [`server/src/web.rs`](https://github.com/LPGhatguy/rojo/blob/master/server/src/web.rs)
-
-The Rojo live-sync server and Roblox Studio plugin communicate via HTTP.
-
-Requests sent from the plugin to the server are regular HTTP requests.
-
-Messages sent from the server to the plugin are delivered via HTTP long-polling. This is an approach that uses long-lived HTTP requests that restart on timeout. It's largely been replaced by WebSockets, but Roblox doesn't have support for them.
-
-## Roblox Studio Plugin
-TODO

docs/reference/full-vs-partial.md

@@ -1,37 +0,0 @@
-Rojo is designed to be adopted incrementally. How much of your project Rojo manages is up to you!
-
-There are two primary categories of ways to use Rojo: *Fully Managed*, where everything is managed by Rojo, and *Partially Managed*, where Rojo only manages a slice of your project.
-
-## Fully Managed
-In a fully managed game project, Rojo controls every instance. A fully managed Rojo project can be built from scratch using `rojo build`.
-
-Fully managed projects are most practical for libraries, plugins, and simple games.
-
-Rojo's goal is to make it practical and easy for _every_ project to be fully managed, but we're not quite there yet!
-
-### Pros
-* Fully reproducible builds from scratch
-* Everything checked into version control
-
-### Cons
-* Without two-way sync, models have to be saved manually
-    * This can be done with the 'Save to File...' menu in Roblox Studio
-    * This will be solved by Two-Way Sync ([issue #164](https://github.com/LPGhatguy/rojo/issues/164))
-* Rojo can't manage everything yet
-    * Refs are currently broken ([issue #142](https://github.com/LPGhatguy/rojo/issues/142))
-
-## Partially Managed
-In a partially managed project, Rojo only handles a slice of the game. This could be as small as a couple scripts, or as large as everything except `Workspace`!
-
-The rest of the place's content can be versioned using Team Create or checked into source control.
-
-Partially managed projects are most practical for complicated games, or games that are migrating to use Rojo.
-
-### Pros
-* Easier to adopt gradually
-* Integrates with Team Create
-
-### Cons
-* Not everything is in version control, which makes merges tougher
-* Rojo can't live-sync instances like Terrain, MeshPart, or CSG operations yet
-    * Will be fixed with plugin escalation ([issue #169](https://github.com/LPGhatguy/rojo/issues/169))

docs/reference/project-format.md

@@ -1,151 +0,0 @@
-[TOC]
-
-## Project File
-Rojo projects are JSON files that have the `.project.json` extension. They have the following fields:
-
-* `name`: A string indicating the name of the project. This name is used when building the project into a model or place file.
-    * **Required**
-* `tree`: An [Instance Description](#instance-description) describing the root instance of the project.
-    * **Required**
-* `servePort`: The port that `rojo serve` should listen on. Passing `--port` will override this setting.
-    * **Optional**
-    * Default is `34872`
-* `servePlaceIds`: A list of place IDs that this project may be live-synced to. This feature can help prevent overwriting the wrong game with source from Rojo.
-    * **Optional**
-    * Default is `null`
-
-## Instance Description
-Instance Descriptions correspond one-to-one with the actual Roblox Instances in the project.
-
-* `$className`: The ClassName of the Instance being described.
-    * **Optional if `$path` is specified.**
-* `$path`: The path on the filesystem to pull files from into the project.
-    * **Optional if `$className` is specified.**
-    * Paths are relative to the folder containing the project file.
-* `$properties`: Properties to apply to the instance. Values should be [Instance Property Values](#instance-property-value).
-    * **Optional**
-* `$ignoreUnknownInstances`: Whether instances that Rojo doesn't know about should be deleted.
-    * **Optional**
-    * Default is `false` if `$path` is specified, otherwise `true`.
-
-All other fields in an Instance Description are turned into instances whose name is the key. These values should also be Instance Descriptions!
-
-Instance Descriptions are fairly verbose and strict. In the future, it'll be possible for Rojo to [infer class names for known services like `Workspace`](https://github.com/LPGhatguy/rojo/issues/179).
-
-## Instance Property Value
-There are two kinds of property values on instances, **implicit** and **explicit**.
-
-In the vast majority of cases, you should be able to use **implicit** property values. To use them, just use a value that's the same shape as the type that the property has:
-
-```json
-"MyPart": {
-    "$className": "Part",
-    "$properties": {
-        "Size": [3, 5, 3],
-        "Color": [0.5, 0, 0.5],
-        "Anchored": true,
-        "Material": "Granite"
-    }
-}
-```
-
-`Vector3` and `Color3` properties can just be arrays of numbers, as can types like `Vector2`, `CFrame`, and more!
-
-Enums can be set to a string containing the enum variant. Rojo will raise an error if the string isn't a valid variant for the enum.
-
-There are some cases where this syntax for assigning properties _doesn't_ work. In these cases, Rojo requires you to use the **explicit** property syntax.
-
-Some reasons why you might need to use an **explicit** property:
-
-* Using exotic property types like `BinaryString`
-* Using properties added to Roblox recently that Rojo doesn't know about yet
-
-The shape of explicit property values is defined by the [rbx-dom](https://github.com/LPGhatguy/rbx-dom) library, so it uses slightly different conventions than the rest of Rojo.
-
-Each value should be an object with the following required fields:
-
-* `Type`: The type of property to represent.
-    * [Supported types can be found here](https://github.com/LPGhatguy/rbx-tree#property-type-coverage).
-* `Value`: The value of the property.
-    * The shape of this field depends on which property type is being used. `Vector3` and `Color3` values are both represented as a list of numbers, while `BinaryString` expects a base64-encoded string, for example.
-
-Here's the same object, but with explicit properties:
-
-```json
-"MyPart": {
-    "$className": "Part",
-    "$properties": {
-        "Size": {
-            "Type": "Vector3",
-            "Value": [3, 5, 3]
-        },
-        "Color": {
-            "Type": "Color3",
-            "Value": [0.5, 0, 0.5]
-        },
-        "Anchored": {
-            "Type": "Bool",
-            "Value": true
-        },
-        "Material": {
-            "Type": "Enum",
-            "Value": 832
-        }
-    }
-}
-```
-
-## Example Projects
-This project bundles up everything in the `src` directory. It'd be suitable for making a plugin or model:
-
-```json
-{
-    "name": "AwesomeLibrary",
-    "tree": {
-        "$path": "src"
-    }
-}
-```
-
-This project describes the layout you might use if you were making the next hit simulator game, *Sisyphus Simulator*:
-
-```json
-{
-    "name": "Sisyphus Simulator",
-    "tree": {
-        "$className": "DataModel",
-
-        "HttpService": {
-            "$className": "HttpService",
-            "$properties": {
-                "HttpEnabled": true
-            }
-        },
-
-        "ReplicatedStorage": {
-            "$className": "ReplicatedStorage",
-            "$path": "src/ReplicatedStorage"
-        },
-
-        "StarterPlayer": {
-            "$className": "StarterPlayer",
-
-            "StarterPlayerScripts": {
-                "$className": "StarterPlayerScripts",
-                "$path": "src/StarterPlayerScripts"
-            }
-        },
-
-        "Workspace": {
-            "$className": "Workspace",
-            "$properties": {
-                "Gravity": 67.3
-            },
-
-            "Terrain": {
-                "$path": "Terrain.rbxm"
-            }
-        }
-    }
-}
-```

docs/reference/sync-details.md

@@ -1,157 +0,0 @@
-This page aims to describe how Rojo turns files on the filesystem into Roblox objects.
-
-[TOC]
-
-## Overview
-| File Name      | Instance Type             |
-| -------------- | ------------------------- |
-| any directory  | `Folder`                  |
-| `*.server.lua` | `Script`                  |
-| `*.client.lua` | `LocalScript`             |
-| `*.lua`        | `ModuleScript`            |
-| `*.csv`        | `LocalizationTable`       |
-| `*.txt`        | `StringValue`             |
-| `*.model.json` | Any                       |
-| `*.rbxm`       | Any                       |
-| `*.rbxmx`      | Any                       |
-| `*.meta.json`  | Modifies another instance |
-
-## Limitations
-Not all property types can be synced by Rojo in real-time due to limitations of the Roblox Studio plugin API. In these cases, you can usually generate a place file and open it when you start working on a project.
-
-Some common cases you might hit are:
-
-* Binary data (Terrain, CSG, CollectionService tags)
-* `MeshPart.MeshId`
-* `HttpService.HttpEnabled`
-
-For a list of all property types that Rojo can reason about, both when live-syncing and when building place files, look at [rbx-dom's type coverage chart](https://github.com/rojo-rbx/rbx-dom#property-type-coverage).
-
-This limitation may be solved by [issue #205](https://github.com/rojo-rbx/rojo/issues/205) in the future.
-
-## Folders
-Any directory on the filesystem will turn into a `Folder` instance unless it contains an 'init' script, described below.
-
-## Scripts
-The default script type in Rojo projects is `ModuleScript`, since most scripts in well-structued Roblox projects will be modules.
-
-If a directory contains a file named `init.server.lua`, `init.client.lua`, or `init.lua`, that folder will be transformed into a `*Script` instance with the contents of the 'init' file. This can be used to create scripts inside of scripts.
-
-For example, these files:
-
-![Tree of files on disk](../images/sync-example-files.svg)
-{: align="center" }
-
-Will turn into these instances in Roblox:
-
-![Tree of instances in Roblox](../images/sync-example-instances.svg)
-{: align="center" }
-
-## Localization Tables
-Any CSV files are transformed into `LocalizationTable` instances. Rojo expects these files to follow the same format that Roblox does when importing and exporting localization information.
-
-## Plain Text Files
-Plain text files (`.txt`) files are transformed into `StringValue` instances. This is useful for bringing in text data that can be read by scripts at runtime.
-
-## JSON Models
-Files ending in `.model.json` can be used to describe simple models. They're designed to be hand-written and are useful for instances like `RemoteEvent`.
-
-A JSON model describing a folder containing a `Part` and a `RemoteEvent` could be described as:
-
-```json
-{
-    "Name": "My Cool Model",
-    "ClassName": "Folder",
-    "Children": [
-        {
-            "Name": "RootPart",
-            "ClassName": "Part",
-            "Properties": {
-                "Size": {
-                    "Type": "Vector3",
-                    "Value": [4, 4, 4]
-                }
-            }
-        },
-        {
-            "Name": "SendMoney",
-            "ClassName": "RemoteEvent"
-        }
-    ]
-}
-```
-
-It would turn into instances in this shape:
-
-![Tree of instances in Roblox](../images/sync-example-json-model.svg)
-{: align="center" }
-
-!!! warning
-    Starting in Rojo 0.5.0 (stable), the `Name` field is no longer required. The name of the top-level instance in a JSON model is now based on its file name, and the `Name` field is now ignored.
-
-    Rojo will emit a warning if the `Name` field is specified and does not match the file's name.
-
-## Binary and XML Models
-Rojo supports both binary (`.rbxm`) and XML (`.rbxmx`) models generated by Roblox Studio or another tool.
-
-Support for the `rbxmx` is very good, while support for `rbxm` is still very early, buggy, and lacking features.
-
-For a rundown of supported types, check out [rbx-dom's type coverage chart](https://github.com/rojo-rbx/rbx-dom#property-type-coverage).
-
-## Meta Files
-New in Rojo 0.5.0-alpha.12 are meta files, named `.meta.json`.
-
-Meta files allow attaching extra Rojo data to models defined in other formats, like Roblox's `rbxm` and `rbxmx` model formats, or even Lua scripts.
-
-This can be used to set Rojo-specific settings like `ignoreUnknownInstances`, or can be used to set properties like `Disabled` on a script.
-
-Meta files can contain:
-
-* `className`: Changes the `className` of a containing `Folder` into something else.
-    * Usable only in `init.meta.json` files
-* `properties`: A map of properties to set on the instance, just like projects
-    * Usable on anything except `.rbxmx`, `.rbxm`, and `.model.json` files, which already have properties
-* `ignoreUnknownInstances`: Works just like `$ignoreUnknownInstances` in project files
-
-### Meta Files to set Rojo metadata
-Sometimes it's useful to apply properties like `ignoreUnknownInstances` on instances that are defined on the filesystem instead of within the project itself.
-
-If your project has `hello.txt` and there are instances underneath it that you want Rojo to ignore when live-syncing, you could create `hello.meta.json` with:
-
-```json
-{
-    "ignoreUnknownInstances": true
-}
-```
-
-### Meta Files for Disabled Scripts
-Meta files can be used to set properties on `Script` instances, like `Disabled`.
-
-If your project has `foo.server.lua` and you want to make sure it would be disabled, you could create a `foo.meta.json` next to it with:
-
-```json
-{
-    "properties": {
-        "Disabled": true
-    }
-}
-```
-
-### Meta Files for Tools
-If you wanted to represent a tool containing a script and a model for its handle, create a directory with an `init.meta.json` file in it:
-
-```json
-{
-    "className": "Tool",
-    "properties": {
-        "Grip": [
-            0, 0, 0,
-            1, 0, 0,
-            0, 1, 0,
-            0, 0, 1
-        ]
-    }
-}
-```
-
-Instead of a `Folder` instance, you'll end up with a `Tool` instance with the `Grip` property set!

docs/requirements.txt

@@ -1,3 +0,0 @@
-mkdocs
-mkdocs-material
-pymdown-extensions

docs/rojo-alternatives.md

@@ -1,23 +0,0 @@
-There are a number of existing plugins for Roblox that move code from the filesystem into Roblox.
-
-Besides Rojo, you might consider:
-
-* [rbxmk by Anaminus](https://github.com/anaminus/rbxmk)
-* [Rofresh by Osyris](https://github.com/osyrisrblx/rofresh)
-* [RbxRefresh by Osyris](https://github.com/osyrisrblx/RbxRefresh)
-* [Studio Bridge by Vocksel](https://github.com/vocksel/studio-bridge)
-* [Elixir by Vocksel](https://github.com/vocksel/elixir)
-* [RbxSync by evaera](https://github.com/evaera/RbxSync)
-* [CodeSync by MemoryPenguin](https://github.com/MemoryPenguin/CodeSync)
-* [rbx-exteditor by MemoryPenguin](https://github.com/MemoryPenguin/rbx-exteditor)
-
-So why did I build Rojo?
-
-Each of these tools solves what is essentially the same problem from a few different angles. The goal of Rojo is to take all of the lessons and ideas learned from these projects and build a tool that can solve this problem for good.
-
-Additionally:
-
-* I think that this tool needs to be built in a compiled language without a runtime, for easy distribution and good performance.
-* I think that the conventions promoted by other sync plugins (`.module.lua` for modules, as well a single sync point) are sub-optimal.
-* I think that I have a good enough understanding of the problem to build something robust.
-* I think that Rojo should be able to do more than just sync code.

docs/why-rojo.md

@@ -1,44 +0,0 @@
-Adding a tool like Rojo to your Roblox workflow can be daunting, but it comes with some key advantages.
-
-[TOC]
-
-## Rojo at RDC 2019
-Nathan Riemer (Kampfkarren) gave a talk at RDC 2019 talking about some of the benefits of using a tool like Rojo.
-
-<iframe style="margin: 0 auto; max-width: 100%" width="560" height="315" src="https://www.youtube-nocookie.com/embed/czlvzEyhaBc" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
-
-## External Text Editors
-Rojo opens the door to use the absolute best text editors in the world and their rich plugin ecosystems.
-
-Some very popular editors include [Visual Studio Code](https://code.visualstudio.com) and [Sublime Text](https://www.sublimetext.com).
-
-These advanced text editors have features like multi-cursor editing, go-to symbol, multi-file regex find and replace, bookmarks and much more.
-
-Many Rojo VS Code users also use extensions like:
-
-* [vscode-rbxlua](https://marketplace.visualstudio.com/items?itemName=AmaranthineCodices.vscode-rbxlua)
-* [Roblox Lua Autocompletes](https://marketplace.visualstudio.com/items?itemName=Kampfkarren.roblox-lua-autofills)
-* [TabNine](https://tabnine.com)
-
-## Version Control
-By building your game (or just the scripts) as individual files on the filesystem, it becomes easy to start using professional-grade version control tools like [Git](https://git-scm.com) and [GitHub](https://github.com).
-
-Hundreds of thousands of companies and individual developers use Git to version their software projects. With Rojo, Roblox developers can take advantage of the best collaboration tool around.
-
-Using a repository hosting service like GitHub or GitLab brings powerful features to Roblox developers like code reviews and issue tracking that professional engineers can't live without.
-
-## TypeScript
-TypeScript enables static type safety, which helps prevent typos and adds unparalleled autocompletion. It also brings features like arrow functions, object destructuring, functional programming methods, and more!
-
-With Rojo, you can use [roblox-ts](https://roblox-ts.github.io) to compile TypeScript to Lua and take advantage of a huge ecosystem of TypeScript tooling.
-
-It's also possible to use other languages that compile to Lua like [MoonScript](https://moonscript.org) and [Haxe](https://haxe.org).
-
-## Other Tools
-There are decades of excellent tools available that operate on files. With Rojo, it's possible to take advantage of any of them!
-
-Popular tools include:
-
-* [luacheck](https://github.com/mpeterv/luacheck), a static analysis tool to help you write better Lua
-* [ripgrep](https://github.com/BurntSushi/ripgrep), an extremely fast code search tool
-* [Tokei](https://github.com/XAMPPRocky/tokei), a tool for statistics like lines of code

foreman.toml

@@ -0,0 +1,3 @@
+[tools]
+rojo = { source = "rojo-rbx/rojo", version = "6.0.0-rc.1" }
+run-in-roblox = { source = "rojo-rbx/run-in-roblox", version = "0.3.0" }

memofs/CHANGELOG.md

@@ -0,0 +1,15 @@
+# memofs Changelog
+
+## Unreleased Changes
+
+## 0.1.3 (2020-11-19)
+* Added `set_watch_enabled` to `Vfs` and `VfsLock` to allow turning off file watching.
+
+## 0.1.2 (2020-03-29)
+* `VfsSnapshot` now implements Serde's `Serialize` and `Deserialize` traits.
+
+## 0.1.1 (2020-03-18)
+* Improved error messages using the [fs-err](https://crates.io/crates/fs-err) crate.
+
+## 0.1.0 (2020-03-10)
+* Initial release

memofs/Cargo.toml

@@ -0,0 +1,17 @@
+[package]
+name = "memofs"
+description = "Virtual filesystem with configurable backends."
+version = "0.1.3"
+authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+edition = "2018"
+readme = "README.md"
+license = "MIT"
+homepage = "https://github.com/rojo-rbx/rojo/tree/master/memofs"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+crossbeam-channel = "0.4.0"
+fs-err = "2.3.0"
+notify = "4.0.15"
+serde = { version = "1.0", features = ["derive"] }

memofs/LICENSE.txt

@@ -0,0 +1,7 @@
+Copyright 2020 The Rojo Developers
+
+Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

memofs/README.md

@@ -0,0 +1,22 @@
+# memofs
+[![Crates.io](https://img.shields.io/crates/v/memofs.svg)](https://crates.io/crates/memofs)
+
+Implementation of a virtual filesystem with a configurable backend and file
+watching.
+
+memofs is currently an unstable minimum viable library. Its primary consumer is
+[Rojo](https://github.com/rojo-rbx/rojo), a build system for Roblox.
+
+### Current Features
+* API similar to `std::fs`
+* Configurable backends
+    * `StdBackend`, which uses `std::fs` and the `notify` crate
+    * `NoopBackend`, which always throws errors
+    * `InMemoryFs`, a simple in-memory filesystem useful for testing
+
+### Future Features
+* Hash-based hierarchical memoization keys (hence the name)
+* Configurable caching (write-through, write-around, write-back)
+
+## License
+memofs is available under the terms of the MIT license. See [LICENSE.txt](LICENSE.txt) or <https://opensource.org/licenses/MIT> for more details.

memofs/README.tpl

@@ -0,0 +1,7 @@
+# {{crate}}
+[![Crates.io](https://img.shields.io/crates/v/memofs.svg)](https://crates.io/crates/memofs)
+
+{{readme}}
+
+## License
+memofs is available under the terms of the MIT license. See [LICENSE.txt](LICENSE.txt) or <https://opensource.org/licenses/MIT> for more details.

memofs/src/in_memory_fs.rs

@@ -0,0 +1,249 @@
+use std::collections::{BTreeSet, HashMap, VecDeque};
+use std::io;
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, Mutex};
+
+use crossbeam_channel::{Receiver, Sender};
+
+use crate::{DirEntry, Metadata, ReadDir, VfsBackend, VfsEvent, VfsSnapshot};
+
+/// In-memory filesystem that can be used as a VFS backend.
+///
+/// Internally reference counted to enable giving a copy to
+/// [`Vfs`](struct.Vfs.html) and keeping the original to mutate the filesystem's
+/// state with.
+#[derive(Debug, Clone)]
+pub struct InMemoryFs {
+    inner: Arc<Mutex<InMemoryFsInner>>,
+}
+
+impl InMemoryFs {
+    /// Create a new empty `InMemoryFs`.
+    pub fn new() -> Self {
+        Self {
+            inner: Arc::new(Mutex::new(InMemoryFsInner::new())),
+        }
+    }
+
+    /// Load a [`VfsSnapshot`](enum.VfsSnapshot.html) into a subtree of the
+    /// in-memory filesystem.
+    ///
+    /// This function will return an error if the operations required to apply
+    /// the snapshot result in errors, like trying to create a file inside a
+    /// file.
+    pub fn load_snapshot<P: Into<PathBuf>>(
+        &mut self,
+        path: P,
+        snapshot: VfsSnapshot,
+    ) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+        inner.load_snapshot(path.into(), snapshot)
+    }
+
+    /// Raises a filesystem change event.
+    ///
+    /// If this `InMemoryFs` is being used as the backend of a
+    /// [`Vfs`](struct.Vfs.html), then any listeners be notified of this event.
+    pub fn raise_event(&mut self, event: VfsEvent) {
+        let inner = self.inner.lock().unwrap();
+        inner.event_sender.send(event).unwrap();
+    }
+}
+
+#[derive(Debug)]
+struct InMemoryFsInner {
+    entries: HashMap<PathBuf, Entry>,
+    orphans: BTreeSet<PathBuf>,
+
+    event_receiver: Receiver<VfsEvent>,
+    event_sender: Sender<VfsEvent>,
+}
+
+impl InMemoryFsInner {
+    fn new() -> Self {
+        let (event_sender, event_receiver) = crossbeam_channel::unbounded();
+
+        Self {
+            entries: HashMap::new(),
+            orphans: BTreeSet::new(),
+            event_receiver,
+            event_sender,
+        }
+    }
+
+    fn load_snapshot(&mut self, path: PathBuf, snapshot: VfsSnapshot) -> io::Result<()> {
+        if let Some(parent_path) = path.parent() {
+            if let Some(parent_entry) = self.entries.get_mut(parent_path) {
+                if let Entry::Dir { children } = parent_entry {
+                    children.insert(path.clone());
+                } else {
+                    return must_be_dir(parent_path);
+                }
+            } else {
+                self.orphans.insert(path.clone());
+            }
+        } else {
+            self.orphans.insert(path.clone());
+        }
+
+        match snapshot {
+            VfsSnapshot::File { contents } => {
+                self.entries.insert(path, Entry::File { contents });
+            }
+            VfsSnapshot::Dir { children } => {
+                self.entries.insert(
+                    path.clone(),
+                    Entry::Dir {
+                        children: BTreeSet::new(),
+                    },
+                );
+
+                for (child_name, child) in children {
+                    let full_path = path.join(child_name);
+                    self.load_snapshot(full_path, child)?;
+                }
+            }
+        }
+
+        Ok(())
+    }
+
+    fn remove(&mut self, root_path: PathBuf) {
+        self.orphans.remove(&root_path);
+
+        let mut to_remove = VecDeque::new();
+        to_remove.push_back(root_path);
+
+        while let Some(path) = to_remove.pop_front() {
+            if let Some(Entry::Dir { children }) = self.entries.remove(&path) {
+                to_remove.extend(children);
+            }
+        }
+    }
+}
+
+#[derive(Debug)]
+enum Entry {
+    File { contents: Vec<u8> },
+
+    Dir { children: BTreeSet<PathBuf> },
+}
+
+impl VfsBackend for InMemoryFs {
+    fn read(&mut self, path: &Path) -> io::Result<Vec<u8>> {
+        let inner = self.inner.lock().unwrap();
+
+        match inner.entries.get(path) {
+            Some(Entry::File { contents }) => Ok(contents.clone()),
+            Some(Entry::Dir { .. }) => must_be_file(path),
+            None => not_found(path),
+        }
+    }
+
+    fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+
+        inner.load_snapshot(
+            path.to_path_buf(),
+            VfsSnapshot::File {
+                contents: data.to_owned(),
+            },
+        )
+    }
+
+    fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
+        let inner = self.inner.lock().unwrap();
+
+        match inner.entries.get(path) {
+            Some(Entry::Dir { children }) => {
+                let iter = children
+                    .clone()
+                    .into_iter()
+                    .map(|path| Ok(DirEntry { path }));
+
+                Ok(ReadDir {
+                    inner: Box::new(iter),
+                })
+            }
+            Some(Entry::File { .. }) => must_be_dir(path),
+            None => not_found(path),
+        }
+    }
+
+    fn remove_file(&mut self, path: &Path) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+
+        match inner.entries.get(path) {
+            Some(Entry::File { .. }) => {
+                inner.remove(path.to_owned());
+                Ok(())
+            }
+            Some(Entry::Dir { .. }) => must_be_file(path),
+            None => not_found(path),
+        }
+    }
+
+    fn remove_dir_all(&mut self, path: &Path) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+
+        match inner.entries.get(path) {
+            Some(Entry::Dir { .. }) => {
+                inner.remove(path.to_owned());
+                Ok(())
+            }
+            Some(Entry::File { .. }) => must_be_dir(path),
+            None => not_found(path),
+        }
+    }
+
+    fn metadata(&mut self, path: &Path) -> io::Result<Metadata> {
+        let inner = self.inner.lock().unwrap();
+
+        match inner.entries.get(path) {
+            Some(Entry::File { .. }) => Ok(Metadata { is_file: true }),
+            Some(Entry::Dir { .. }) => Ok(Metadata { is_file: false }),
+            None => not_found(path),
+        }
+    }
+
+    fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        let inner = self.inner.lock().unwrap();
+
+        inner.event_receiver.clone()
+    }
+
+    fn watch(&mut self, _path: &Path) -> io::Result<()> {
+        Ok(())
+    }
+
+    fn unwatch(&mut self, _path: &Path) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+fn must_be_file<T>(path: &Path) -> io::Result<T> {
+    Err(io::Error::new(
+        io::ErrorKind::Other,
+        format!(
+            "path {} was a directory, but must be a file",
+            path.display()
+        ),
+    ))
+}
+
+fn must_be_dir<T>(path: &Path) -> io::Result<T> {
+    Err(io::Error::new(
+        io::ErrorKind::Other,
+        format!(
+            "path {} was a file, but must be a directory",
+            path.display()
+        ),
+    ))
+}
+
+fn not_found<T>(path: &Path) -> io::Result<T> {
+    Err(io::Error::new(
+        io::ErrorKind::NotFound,
+        format!("path {} not found", path.display()),
+    ))
+}

memofs/src/lib.rs

@@ -0,0 +1,433 @@
+/*!
+Implementation of a virtual filesystem with a configurable backend and file
+watching.
+
+memofs is currently an unstable minimum viable library. Its primary consumer is
+[Rojo](https://github.com/rojo-rbx/rojo), a build system for Roblox.
+
+## Current Features
+* API similar to `std::fs`
+* Configurable backends
+    * `StdBackend`, which uses `std::fs` and the `notify` crate
+    * `NoopBackend`, which always throws errors
+    * `InMemoryFs`, a simple in-memory filesystem useful for testing
+
+## Future Features
+* Hash-based hierarchical memoization keys (hence the name)
+* Configurable caching (write-through, write-around, write-back)
+*/
+
+mod in_memory_fs;
+mod noop_backend;
+mod snapshot;
+mod std_backend;
+
+use std::io;
+use std::path::{Path, PathBuf};
+use std::sync::{Arc, Mutex, MutexGuard};
+
+pub use in_memory_fs::InMemoryFs;
+pub use noop_backend::NoopBackend;
+pub use snapshot::VfsSnapshot;
+pub use std_backend::StdBackend;
+
+mod sealed {
+    use super::*;
+
+    /// Sealing trait for VfsBackend.
+    pub trait Sealed {}
+
+    impl Sealed for NoopBackend {}
+    impl Sealed for StdBackend {}
+    impl Sealed for InMemoryFs {}
+}
+
+/// Trait that transforms `io::Result<T>` into `io::Result<Option<T>>`.
+///
+/// `Ok(None)` takes the place of IO errors whose `io::ErrorKind` is `NotFound`.
+pub trait IoResultExt<T> {
+    fn with_not_found(self) -> io::Result<Option<T>>;
+}
+
+impl<T> IoResultExt<T> for io::Result<T> {
+    fn with_not_found(self) -> io::Result<Option<T>> {
+        match self {
+            Ok(v) => Ok(Some(v)),
+            Err(err) => {
+                if err.kind() == io::ErrorKind::NotFound {
+                    Ok(None)
+                } else {
+                    Err(err)
+                }
+            }
+        }
+    }
+}
+
+/// Backend that can be used to create a `Vfs`.
+///
+/// This trait is sealed and cannot not be implemented outside this crate.
+pub trait VfsBackend: sealed::Sealed + Send + 'static {
+    fn read(&mut self, path: &Path) -> io::Result<Vec<u8>>;
+    fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()>;
+    fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir>;
+    fn metadata(&mut self, path: &Path) -> io::Result<Metadata>;
+    fn remove_file(&mut self, path: &Path) -> io::Result<()>;
+    fn remove_dir_all(&mut self, path: &Path) -> io::Result<()>;
+
+    fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent>;
+    fn watch(&mut self, path: &Path) -> io::Result<()>;
+    fn unwatch(&mut self, path: &Path) -> io::Result<()>;
+}
+
+/// Vfs equivalent to [`std::fs::DirEntry`][std::fs::DirEntry].
+///
+/// [std::fs::DirEntry]: https://doc.rust-lang.org/stable/std/fs/struct.DirEntry.html
+pub struct DirEntry {
+    pub(crate) path: PathBuf,
+}
+
+impl DirEntry {
+    pub fn path(&self) -> &Path {
+        &self.path
+    }
+}
+
+/// Vfs equivalent to [`std::fs::ReadDir`][std::fs::ReadDir].
+///
+/// [std::fs::ReadDir]: https://doc.rust-lang.org/stable/std/fs/struct.ReadDir.html
+pub struct ReadDir {
+    pub(crate) inner: Box<dyn Iterator<Item = io::Result<DirEntry>>>,
+}
+
+impl Iterator for ReadDir {
+    type Item = io::Result<DirEntry>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        self.inner.next()
+    }
+}
+
+/// Vfs equivalent to [`std::fs::Metadata`][std::fs::Metadata].
+///
+/// [std::fs::Metadata]: https://doc.rust-lang.org/stable/std/fs/struct.Metadata.html
+#[derive(Debug)]
+pub struct Metadata {
+    pub(crate) is_file: bool,
+}
+
+impl Metadata {
+    pub fn is_file(&self) -> bool {
+        self.is_file
+    }
+
+    pub fn is_dir(&self) -> bool {
+        !self.is_file
+    }
+}
+
+/// Represents an event that a filesystem can raise that might need to be
+/// handled.
+#[derive(Debug)]
+#[non_exhaustive]
+pub enum VfsEvent {
+    Create(PathBuf),
+    Write(PathBuf),
+    Remove(PathBuf),
+}
+
+/// Contains implementation details of the Vfs, wrapped by `Vfs` and `VfsLock`,
+/// the public interfaces to this type.
+struct VfsInner {
+    backend: Box<dyn VfsBackend>,
+    watch_enabled: bool,
+}
+
+impl VfsInner {
+    fn read<P: AsRef<Path>>(&mut self, path: P) -> io::Result<Arc<Vec<u8>>> {
+        let path = path.as_ref();
+        let contents = self.backend.read(path)?;
+
+        if self.watch_enabled {
+            self.backend.watch(path)?;
+        }
+
+        Ok(Arc::new(contents))
+    }
+
+    fn write<P: AsRef<Path>, C: AsRef<[u8]>>(&mut self, path: P, contents: C) -> io::Result<()> {
+        let path = path.as_ref();
+        let contents = contents.as_ref();
+        self.backend.write(path, contents)
+    }
+
+    fn read_dir<P: AsRef<Path>>(&mut self, path: P) -> io::Result<ReadDir> {
+        let path = path.as_ref();
+        let dir = self.backend.read_dir(path)?;
+
+        if self.watch_enabled {
+            self.backend.watch(path)?;
+        }
+
+        Ok(dir)
+    }
+
+    fn remove_file<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        let _ = self.backend.unwatch(path);
+        self.backend.remove_file(path)
+    }
+
+    fn remove_dir_all<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        let _ = self.backend.unwatch(path);
+        self.backend.remove_dir_all(path)
+    }
+
+    fn metadata<P: AsRef<Path>>(&mut self, path: P) -> io::Result<Metadata> {
+        let path = path.as_ref();
+        self.backend.metadata(path)
+    }
+
+    fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        self.backend.event_receiver()
+    }
+
+    fn commit_event(&mut self, event: &VfsEvent) -> io::Result<()> {
+        match event {
+            VfsEvent::Remove(path) => {
+                let _ = self.backend.unwatch(&path);
+            }
+            _ => {}
+        }
+
+        Ok(())
+    }
+}
+
+/// A virtual filesystem with a configurable backend.
+///
+/// All operations on the Vfs take a lock on an internal backend. For performing
+/// large batches of operations, it might be more performant to call `lock()`
+/// and use [`VfsLock`](struct.VfsLock.html) instead.
+pub struct Vfs {
+    inner: Mutex<VfsInner>,
+}
+
+impl Vfs {
+    /// Creates a new `Vfs` with the default backend, `StdBackend`.
+    pub fn new_default() -> Self {
+        Self::new(StdBackend::new())
+    }
+
+    /// Creates a new `Vfs` with the given backend.
+    pub fn new<B: VfsBackend>(backend: B) -> Self {
+        let lock = VfsInner {
+            backend: Box::new(backend),
+            watch_enabled: true,
+        };
+
+        Self {
+            inner: Mutex::new(lock),
+        }
+    }
+
+    /// Manually lock the Vfs, useful for large batches of operations.
+    pub fn lock(&self) -> VfsLock<'_> {
+        VfsLock {
+            inner: self.inner.lock().unwrap(),
+        }
+    }
+
+    /// Turns automatic file watching on or off. Enabled by default.
+    ///
+    /// Turning off file watching may be useful for single-use cases, especially
+    /// on platforms like macOS where registering file watches has significant
+    /// performance cost.
+    pub fn set_watch_enabled(&self, enabled: bool) {
+        let mut inner = self.inner.lock().unwrap();
+        inner.watch_enabled = enabled;
+    }
+
+    /// Read a file from the VFS, or the underlying backend if it isn't
+    /// resident.
+    ///
+    /// Roughly equivalent to [`std::fs::read`][std::fs::read].
+    ///
+    /// [std::fs::read]: https://doc.rust-lang.org/stable/std/fs/fn.read.html
+    #[inline]
+    pub fn read<P: AsRef<Path>>(&self, path: P) -> io::Result<Arc<Vec<u8>>> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().read(path)
+    }
+
+    /// Write a file to the VFS and the underlying backend.
+    ///
+    /// Roughly equivalent to [`std::fs::write`][std::fs::write].
+    ///
+    /// [std::fs::write]: https://doc.rust-lang.org/stable/std/fs/fn.write.html
+    #[inline]
+    pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(&self, path: P, contents: C) -> io::Result<()> {
+        let path = path.as_ref();
+        let contents = contents.as_ref();
+        self.inner.lock().unwrap().write(path, contents)
+    }
+
+    /// Read all of the children of a directory.
+    ///
+    /// Roughly equivalent to [`std::fs::read_dir`][std::fs::read_dir].
+    ///
+    /// [std::fs::read_dir]: https://doc.rust-lang.org/stable/std/fs/fn.read_dir.html
+    #[inline]
+    pub fn read_dir<P: AsRef<Path>>(&self, path: P) -> io::Result<ReadDir> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().read_dir(path)
+    }
+
+    /// Remove a file.
+    ///
+    /// Roughly equivalent to [`std::fs::remove_file`][std::fs::remove_file].
+    ///
+    /// [std::fs::remove_file]: https://doc.rust-lang.org/stable/std/fs/fn.remove_file.html
+    #[inline]
+    pub fn remove_file<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().remove_file(path)
+    }
+
+    /// Remove a directory and all of its descendants.
+    ///
+    /// Roughly equivalent to [`std::fs::remove_dir_all`][std::fs::remove_dir_all].
+    ///
+    /// [std::fs::remove_dir_all]: https://doc.rust-lang.org/stable/std/fs/fn.remove_dir_all.html
+    #[inline]
+    pub fn remove_dir_all<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().remove_dir_all(path)
+    }
+
+    /// Query metadata about the given path.
+    ///
+    /// Roughly equivalent to [`std::fs::metadata`][std::fs::metadata].
+    ///
+    /// [std::fs::metadata]: https://doc.rust-lang.org/stable/std/fs/fn.metadata.html
+    #[inline]
+    pub fn metadata<P: AsRef<Path>>(&self, path: P) -> io::Result<Metadata> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().metadata(path)
+    }
+
+    /// Retrieve a handle to the event receiver for this `Vfs`.
+    #[inline]
+    pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        self.inner.lock().unwrap().event_receiver()
+    }
+
+    /// Commit an event to this `Vfs`.
+    #[inline]
+    pub fn commit_event(&self, event: &VfsEvent) -> io::Result<()> {
+        self.inner.lock().unwrap().commit_event(event)
+    }
+}
+
+/// A locked handle to a [`Vfs`](struct.Vfs.html), created by `Vfs::lock`.
+///
+/// Implements roughly the same API as [`Vfs`](struct.Vfs.html).
+pub struct VfsLock<'a> {
+    inner: MutexGuard<'a, VfsInner>,
+}
+
+impl VfsLock<'_> {
+    /// Turns automatic file watching on or off. Enabled by default.
+    ///
+    /// Turning off file watching may be useful for single-use cases, especially
+    /// on platforms like macOS where registering file watches has significant
+    /// performance cost.
+    pub fn set_watch_enabled(&mut self, enabled: bool) {
+        self.inner.watch_enabled = enabled;
+    }
+
+    /// Read a file from the VFS, or the underlying backend if it isn't
+    /// resident.
+    ///
+    /// Roughly equivalent to [`std::fs::read`][std::fs::read].
+    ///
+    /// [std::fs::read]: https://doc.rust-lang.org/stable/std/fs/fn.read.html
+    #[inline]
+    pub fn read<P: AsRef<Path>>(&mut self, path: P) -> io::Result<Arc<Vec<u8>>> {
+        let path = path.as_ref();
+        self.inner.read(path)
+    }
+
+    /// Write a file to the VFS and the underlying backend.
+    ///
+    /// Roughly equivalent to [`std::fs::write`][std::fs::write].
+    ///
+    /// [std::fs::write]: https://doc.rust-lang.org/stable/std/fs/fn.write.html
+    #[inline]
+    pub fn write<P: AsRef<Path>, C: AsRef<[u8]>>(
+        &mut self,
+        path: P,
+        contents: C,
+    ) -> io::Result<()> {
+        let path = path.as_ref();
+        let contents = contents.as_ref();
+        self.inner.write(path, contents)
+    }
+
+    /// Read all of the children of a directory.
+    ///
+    /// Roughly equivalent to [`std::fs::read_dir`][std::fs::read_dir].
+    ///
+    /// [std::fs::read_dir]: https://doc.rust-lang.org/stable/std/fs/fn.read_dir.html
+    #[inline]
+    pub fn read_dir<P: AsRef<Path>>(&mut self, path: P) -> io::Result<ReadDir> {
+        let path = path.as_ref();
+        self.inner.read_dir(path)
+    }
+
+    /// Remove a file.
+    ///
+    /// Roughly equivalent to [`std::fs::remove_file`][std::fs::remove_file].
+    ///
+    /// [std::fs::remove_file]: https://doc.rust-lang.org/stable/std/fs/fn.remove_file.html
+    #[inline]
+    pub fn remove_file<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.remove_file(path)
+    }
+
+    /// Remove a directory and all of its descendants.
+    ///
+    /// Roughly equivalent to [`std::fs::remove_dir_all`][std::fs::remove_dir_all].
+    ///
+    /// [std::fs::remove_dir_all]: https://doc.rust-lang.org/stable/std/fs/fn.remove_dir_all.html
+    #[inline]
+    pub fn remove_dir_all<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.remove_dir_all(path)
+    }
+
+    /// Query metadata about the given path.
+    ///
+    /// Roughly equivalent to [`std::fs::metadata`][std::fs::metadata].
+    ///
+    /// [std::fs::metadata]: https://doc.rust-lang.org/stable/std/fs/fn.metadata.html
+    #[inline]
+    pub fn metadata<P: AsRef<Path>>(&mut self, path: P) -> io::Result<Metadata> {
+        let path = path.as_ref();
+        self.inner.metadata(path)
+    }
+
+    /// Retrieve a handle to the event receiver for this `Vfs`.
+    #[inline]
+    pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        self.inner.event_receiver()
+    }
+
+    /// Commit an event to this `Vfs`.
+    #[inline]
+    pub fn commit_event(&mut self, event: &VfsEvent) -> io::Result<()> {
+        self.inner.commit_event(event)
+    }
+}

memofs/src/noop_backend.rs

@@ -0,0 +1,76 @@
+use std::io;
+use std::path::Path;
+
+use crate::{Metadata, ReadDir, VfsBackend, VfsEvent};
+
+/// `VfsBackend` that returns an error on every operation.
+#[non_exhaustive]
+pub struct NoopBackend;
+
+impl NoopBackend {
+    pub fn new() -> Self {
+        Self
+    }
+}
+
+impl VfsBackend for NoopBackend {
+    fn read(&mut self, _path: &Path) -> io::Result<Vec<u8>> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn write(&mut self, _path: &Path, _data: &[u8]) -> io::Result<()> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn read_dir(&mut self, _path: &Path) -> io::Result<ReadDir> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn remove_file(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn remove_dir_all(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn metadata(&mut self, _path: &Path) -> io::Result<Metadata> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        crossbeam_channel::never()
+    }
+
+    fn watch(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+
+    fn unwatch(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::new(
+            io::ErrorKind::Other,
+            "NoopBackend doesn't do anything",
+        ))
+    }
+}

memofs/src/snapshot.rs

@@ -0,0 +1,45 @@
+use serde::{Deserialize, Serialize};
+use std::collections::BTreeMap;
+
+/// A slice of a tree of files. Can be loaded into an
+/// [`InMemoryFs`](struct.InMemoryFs.html).
+#[derive(Debug, Serialize, Deserialize)]
+#[non_exhaustive]
+pub enum VfsSnapshot {
+    File {
+        contents: Vec<u8>,
+    },
+
+    Dir {
+        children: BTreeMap<String, VfsSnapshot>,
+    },
+}
+
+impl VfsSnapshot {
+    pub fn file<C: Into<Vec<u8>>>(contents: C) -> Self {
+        Self::File {
+            contents: contents.into(),
+        }
+    }
+
+    pub fn dir<K: Into<String>, I: IntoIterator<Item = (K, VfsSnapshot)>>(children: I) -> Self {
+        Self::Dir {
+            children: children
+                .into_iter()
+                .map(|(key, value)| (key.into(), value))
+                .collect(),
+        }
+    }
+
+    pub fn empty_file() -> Self {
+        Self::File {
+            contents: Vec::new(),
+        }
+    }
+
+    pub fn empty_dir() -> Self {
+        Self::Dir {
+            children: BTreeMap::new(),
+        }
+    }
+}

memofs/src/std_backend.rs

@@ -0,0 +1,110 @@
+use std::io;
+use std::path::Path;
+use std::sync::mpsc;
+use std::thread;
+use std::time::Duration;
+
+use crossbeam_channel::Receiver;
+use notify::{watcher, DebouncedEvent, RecommendedWatcher, RecursiveMode, Watcher};
+
+use crate::{DirEntry, Metadata, ReadDir, VfsBackend, VfsEvent};
+
+/// `VfsBackend` that uses `std::fs` and the `notify` crate.
+pub struct StdBackend {
+    watcher: RecommendedWatcher,
+    watcher_receiver: Receiver<VfsEvent>,
+}
+
+impl StdBackend {
+    pub fn new() -> StdBackend {
+        let (notify_tx, notify_rx) = mpsc::channel();
+        let watcher = watcher(notify_tx, Duration::from_millis(50)).unwrap();
+
+        let (tx, rx) = crossbeam_channel::unbounded();
+
+        thread::spawn(move || {
+            for event in notify_rx {
+                match event {
+                    DebouncedEvent::Create(path) => {
+                        tx.send(VfsEvent::Create(path))?;
+                    }
+                    DebouncedEvent::Write(path) => {
+                        tx.send(VfsEvent::Write(path))?;
+                    }
+                    DebouncedEvent::Remove(path) => {
+                        tx.send(VfsEvent::Remove(path))?;
+                    }
+                    DebouncedEvent::Rename(from, to) => {
+                        tx.send(VfsEvent::Remove(from))?;
+                        tx.send(VfsEvent::Create(to))?;
+                    }
+                    _ => {}
+                }
+            }
+
+            Result::<(), crossbeam_channel::SendError<VfsEvent>>::Ok(())
+        });
+
+        Self {
+            watcher,
+            watcher_receiver: rx,
+        }
+    }
+}
+
+impl VfsBackend for StdBackend {
+    fn read(&mut self, path: &Path) -> io::Result<Vec<u8>> {
+        fs_err::read(path)
+    }
+
+    fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()> {
+        fs_err::write(path, data)
+    }
+
+    fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
+        let entries: Result<Vec<_>, _> = fs_err::read_dir(path)?.collect();
+        let mut entries = entries?;
+
+        entries.sort_by_cached_key(|entry| entry.file_name());
+
+        let inner = entries
+            .into_iter()
+            .map(|entry| Ok(DirEntry { path: entry.path() }));
+
+        Ok(ReadDir {
+            inner: Box::new(inner),
+        })
+    }
+
+    fn remove_file(&mut self, path: &Path) -> io::Result<()> {
+        fs_err::remove_file(path)
+    }
+
+    fn remove_dir_all(&mut self, path: &Path) -> io::Result<()> {
+        fs_err::remove_dir_all(path)
+    }
+
+    fn metadata(&mut self, path: &Path) -> io::Result<Metadata> {
+        let inner = fs_err::metadata(path)?;
+
+        Ok(Metadata {
+            is_file: inner.is_file(),
+        })
+    }
+
+    fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
+        self.watcher_receiver.clone()
+    }
+
+    fn watch(&mut self, path: &Path) -> io::Result<()> {
+        self.watcher
+            .watch(path, RecursiveMode::NonRecursive)
+            .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
+    }
+
+    fn unwatch(&mut self, path: &Path) -> io::Result<()> {
+        self.watcher
+            .unwatch(path)
+            .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
+    }
+}

mkdocs.yml

@@ -1,37 +0,0 @@
-site_name: Rojo Documentation
-repo_name: rojo-rbx/rojo
-repo_url: https://github.com/rojo-rbx/rojo
-
-theme:
-  name: material
-  palette:
-    primary: 'Red'
-    accent: 'Red'
-
-nav:
-  - Home: index.md
-  - Why Rojo?: why-rojo.md
-  - Get Help with Rojo: help.md
-  - Guide:
-    - Installation: guide/installation.md
-    - Creating a Game with Rojo: guide/new-game.md
-    - Porting an Existing Game to Rojo: guide/existing-game.md
-    - Migrating from 0.4.x to 0.5.x: guide/migrating-to-epiphany.md
-  - Reference:
-    - Fully vs Partially Managed Rojo: reference/full-vs-partial.md
-    - Project Format: reference/project-format.md
-    - Sync Details: reference/sync-details.md
-  - Rojo Alternatives: rojo-alternatives.md
-  - Rojo Internals:
-    - Internals Overview: internals/overview.md
-
-extra_css:
-  - extra.css
-
-markdown_extensions:
-  - attr_list
-  - admonition
-  - codehilite:
-      guess_lang: false
-  - toc:
-      permalink: true

perf-test.sh

@@ -0,0 +1,10 @@
+#!/bin/sh
+set -e
+
+cargo build --release
+
+echo "Known good:"
+time rojo build ../uiblox/test-place.project.json -o UIBlox.rbxlx
+
+echo "Current:"
+time ./target/release/rojo build ../uiblox/test-place.project.json -o UIBlox.rbxlx

plugin/default.project.json

@@ -14,6 +14,9 @@
     "Fmt": {
       "$path": "fmt"
     },
+    "RbxDom": {
+      "$path": "rbx_dom_lua"
+    },
     "Roact": {
       "$path": "modules/roact/src"
     },
@@ -22,9 +25,6 @@
     },
     "t": {
       "$path": "modules/t/lib"
-    },
-    "RbxDom": {
-      "$path": "modules/rbx-dom/rbx_dom_lua/src"
     }
   }
 }

plugin/log/init.lua

@@ -53,4 +53,8 @@ function Log.warn(template, ...)
 	end
 end
 
+function Log.error(template, ...)
+	error(Fmt.fmt(template, ...))
+end
+
 return Log

plugin/rbx_dom_lua/.luacheckrc

@@ -0,0 +1,44 @@
+stds.roblox = {
+	read_globals = {
+		game = {
+			other_fields = true,
+		},
+
+		-- Roblox globals
+		"script",
+
+		-- Extra functions
+		"tick", "warn",
+		"wait", "typeof",
+
+		-- Types
+		"CFrame",
+		"Color3",
+		"Enum",
+		"Instance",
+		"NumberRange",
+		"Rect",
+		"UDim", "UDim2",
+		"Vector2", "Vector3",
+		"Vector2int16", "Vector3int16",
+	}
+}
+
+stds.testez = {
+	read_globals = {
+		"describe",
+		"it", "itFOCUS", "itSKIP",
+		"FOCUS", "SKIP", "HACK_NO_XPCALL",
+		"expect",
+	}
+}
+
+ignore = {
+	"212", -- unused arguments
+}
+
+std = "lua51+roblox"
+
+files["**/*.spec.lua"] = {
+	std = "+testez",
+}

plugin/rbx_dom_lua/README.md

@@ -0,0 +1,2 @@
+# rbx_dom_lua
+Roblox Lua implementation of rbx-dom mechanisms, intended to work with rbx_dom_weak and friends.

plugin/rbx_dom_lua/default.project.json

@@ -0,0 +1,6 @@
+{
+  "name": "rbx_dom_lua",
+  "tree": {
+    "$path": "src"
+  }
+}

plugin/rbx_dom_lua/src/EncodedValue.lua

@@ -0,0 +1,242 @@
+local base64 = require(script.Parent.base64)
+
+local function identity(...)
+	return ...
+end
+
+local function unpackDecoder(f)
+	return function(value)
+		return f(unpack(value))
+	end
+end
+
+local function serializeFloat(value)
+	-- TODO: Figure out a better way to serialize infinity and NaN, neither of
+	-- which fit into JSON.
+	if value == math.huge or value == -math.huge then
+		return 999999999 * math.sign(value)
+	end
+
+	return value
+end
+
+local encoders
+encoders = {
+	Bool = identity,
+	Content = identity,
+	Float32 = serializeFloat,
+	Float64 = serializeFloat,
+	Int32 = identity,
+	Int64 = identity,
+	String = identity,
+
+	BinaryString = base64.encode,
+	SharedString = base64.encode,
+
+	BrickColor = function(value)
+		return value.Number
+	end,
+
+	CFrame = function(value)
+		return {value:GetComponents()}
+	end,
+	Color3 = function(value)
+		return {value.r, value.g, value.b}
+	end,
+	NumberRange = function(value)
+		return {value.Min, value.Max}
+	end,
+	NumberSequence = function(value)
+		local keypoints = {}
+
+		for index, keypoint in ipairs(value.Keypoints) do
+			keypoints[index] = {
+				Time = keypoint.Time,
+				Value = keypoint.Value,
+				Envelope = keypoint.Envelope,
+			}
+		end
+
+		return {
+			Keypoints = keypoints,
+		}
+	end,
+	ColorSequence = function(value)
+		local keypoints = {}
+
+		for index, keypoint in ipairs(value.Keypoints) do
+			keypoints[index] = {
+				Time = keypoint.Time,
+				Color = encoders.Color3(keypoint.Value),
+			}
+		end
+
+		return {
+			Keypoints = keypoints,
+		}
+	end,
+	Rect = function(value)
+		return {
+			Min = {value.Min.X, value.Min.Y},
+			Max = {value.Max.X, value.Max.Y},
+		}
+	end,
+	UDim = function(value)
+		return {value.Scale, value.Offset}
+	end,
+	UDim2 = function(value)
+		return {value.X.Scale, value.X.Offset, value.Y.Scale, value.Y.Offset}
+	end,
+	Vector2 = function(value)
+		return {
+			serializeFloat(value.X),
+			serializeFloat(value.Y),
+		}
+	end,
+	Vector2int16 = function(value)
+		return {value.X, value.Y}
+	end,
+	Vector3 = function(value)
+		return {
+			serializeFloat(value.X),
+			serializeFloat(value.Y),
+			serializeFloat(value.Z),
+		}
+	end,
+	Vector3int16 = function(value)
+		return {value.X, value.Y, value.Z}
+	end,
+
+	PhysicalProperties = function(value)
+		if value == nil then
+			return nil
+		else
+			return {
+				Density = value.Density,
+				Friction = value.Friction,
+				Elasticity = value.Elasticity,
+				FrictionWeight = value.FrictionWeight,
+				ElasticityWeight = value.ElasticityWeight,
+			}
+		end
+	end,
+
+	Ref = function(value)
+		return nil
+	end,
+}
+
+local decoders = {
+	Bool = identity,
+	Content = identity,
+	Enum = identity,
+	Float32 = identity,
+	Float64 = identity,
+	Int32 = identity,
+	Int64 = identity,
+	String = identity,
+
+	BinaryString = base64.decode,
+	SharedString = base64.decode,
+
+	BrickColor = BrickColor.new,
+
+	CFrame = unpackDecoder(CFrame.new),
+	Color3 = unpackDecoder(Color3.new),
+	Color3uint8 = unpackDecoder(Color3.fromRGB),
+	NumberRange = unpackDecoder(NumberRange.new),
+	UDim = unpackDecoder(UDim.new),
+	UDim2 = unpackDecoder(UDim2.new),
+	Vector2 = unpackDecoder(Vector2.new),
+	Vector2int16 = unpackDecoder(Vector2int16.new),
+	Vector3 = unpackDecoder(Vector3.new),
+	Vector3int16 = unpackDecoder(Vector3int16.new),
+
+	Rect = function(value)
+		return Rect.new(value.Min[1], value.Min[2], value.Max[1], value.Max[2])
+	end,
+
+	NumberSequence = function(value)
+		local keypoints = {}
+
+		for index, keypoint in ipairs(value.Keypoints) do
+			keypoints[index] = NumberSequenceKeypoint.new(
+				keypoint.Time,
+				keypoint.Value,
+				keypoint.Envelope
+			)
+		end
+
+		return NumberSequence.new(keypoints)
+	end,
+
+	ColorSequence = function(value)
+		local keypoints = {}
+
+		for index, keypoint in ipairs(value.Keypoints) do
+			keypoints[index] = ColorSequenceKeypoint.new(
+				keypoint.Time,
+				Color3.new(unpack(keypoint.Color))
+			)
+		end
+
+		return ColorSequence.new(keypoints)
+	end,
+
+	PhysicalProperties = function(properties)
+		if properties == nil then
+			return nil
+		else
+			return PhysicalProperties.new(
+				properties.Density,
+				properties.Friction,
+				properties.Elasticity,
+				properties.FrictionWeight,
+				properties.ElasticityWeight
+			)
+		end
+	end,
+
+	Ref = function()
+		return nil
+	end,
+}
+
+local EncodedValue = {}
+
+function EncodedValue.decode(encodedValue)
+	local decoder = decoders[encodedValue.Type]
+	if decoder ~= nil then
+		return true, decoder(encodedValue.Value)
+	end
+
+	return false, "Couldn't decode value " .. tostring(encodedValue.Type)
+end
+
+function EncodedValue.encode(rbxValue, propertyType)
+	assert(propertyType ~= nil, "Property type descriptor is required")
+
+	if propertyType.type == "Data" then
+		local encoder = encoders[propertyType.name]
+
+		if encoder == nil then
+			return false, ("Missing encoder for property type %q"):format(propertyType.name)
+		end
+
+		if encoder ~= nil then
+			return true, {
+				Type = propertyType.name,
+				Value = encoder(rbxValue),
+			}
+		end
+	elseif propertyType.type == "Enum" then
+		return true, {
+			Type = "Enum",
+			Value = rbxValue.Value,
+		}
+	end
+
+	return false, ("Unknown property descriptor type %q"):format(tostring(propertyType.type))
+end
+
+return EncodedValue

plugin/rbx_dom_lua/src/EncodedValue.spec.lua

@@ -0,0 +1,127 @@
+return function()
+	local RbxDom = require(script.Parent)
+	local EncodedValue = require(script.Parent.EncodedValue)
+
+	it("should decode Rect values", function()
+		local input = {
+			Type = "Rect",
+			Value = {
+				Min = {1, 2},
+				Max = {3, 4},
+			},
+		}
+
+		local output = Rect.new(1, 2, 3, 4)
+
+		local ok, decoded = EncodedValue.decode(input)
+
+		assert(ok, decoded)
+		expect(decoded).to.equal(output)
+	end)
+
+	it("should decode ColorSequence values", function()
+		local input = {
+			Type = "ColorSequence",
+			Value = {
+				Keypoints = {
+					{
+						Time = 0,
+						Color = { 0.12, 0.34, 0.56 },
+					},
+
+					{
+						Time = 1,
+						Color = { 0.13, 0.33, 0.37 },
+					},
+				}
+			},
+		}
+
+		local output = ColorSequence.new({
+			ColorSequenceKeypoint.new(0, Color3.new(0.12, 0.34, 0.56)),
+			ColorSequenceKeypoint.new(1, Color3.new(0.13, 0.33, 0.37)),
+		})
+
+		local ok, decoded = EncodedValue.decode(input)
+		assert(ok, decoded)
+		expect(decoded).to.equal(output)
+	end)
+
+	it("should decode NumberSequence values", function()
+		local input = {
+			Type = "NumberSequence",
+			Value = {
+				Keypoints = {
+					{
+						Time = 0,
+						Value = 0.5,
+						Envelope = 0,
+					},
+
+					{
+						Time = 1,
+						Value = 0.5,
+						Envelope = 0,
+					},
+				}
+			},
+		}
+
+		local output = NumberSequence.new({
+			NumberSequenceKeypoint.new(0, 0.5, 0),
+			NumberSequenceKeypoint.new(1, 0.5, 0),
+		})
+
+		local ok, decoded = EncodedValue.decode(input)
+		assert(ok, decoded)
+		expect(decoded).to.equal(output)
+	end)
+
+	it("should decode PhysicalProperties values", function()
+		local input = {
+			Type = "PhysicalProperties",
+			Value = {
+				Density = 0.1,
+				Friction = 0.2,
+				Elasticity = 0.3,
+				FrictionWeight = 0.4,
+				ElasticityWeight = 0.5,
+			},
+		}
+
+		local output = PhysicalProperties.new(
+			0.1,
+			0.2,
+			0.3,
+			0.4,
+			0.5
+		)
+
+		local ok, decoded = EncodedValue.decode(input)
+		assert(ok, decoded)
+		expect(decoded).to.equal(output)
+	end)
+
+	-- This part of rbx_dom_lua needs some work still.
+	itSKIP("should encode Rect values", function()
+		local input = Rect.new(10, 20, 30, 40)
+
+		local output = {
+			Type = "Rect",
+			Value = {
+				Min = {10, 20},
+				Max = {30, 40},
+			},
+		}
+
+		local descriptor = RbxDom.findCanonicalPropertyDescriptor("ImageLabel", "SliceCenter")
+		local ok, encoded = EncodedValue.encode(input, descriptor)
+
+		assert(ok, encoded)
+		expect(encoded.Type).to.equal(output.Type)
+		expect(encoded.Value.Min[1]).to.equal(output.Value.Min[1])
+		expect(encoded.Value.Min[2]).to.equal(output.Value.Min[2])
+		expect(encoded.Value.Max[1]).to.equal(output.Value.Max[1])
+		expect(encoded.Value.Max[2]).to.equal(output.Value.Max[2])
+	end)
+end

plugin/rbx_dom_lua/src/Error.lua

@@ -0,0 +1,28 @@
+local Error = {}
+Error.__index = Error
+
+Error.Kind = {
+	UnknownProperty = "UnknownProperty",
+	PropertyNotReadable = "PropertyNotReadable",
+	PropertyNotWritable = "PropertyNotWritable",
+	Roblox = "Roblox",
+}
+
+setmetatable(Error.Kind, {
+	__index = function(_, key)
+		error(("%q is not a valid member of Error.Kind"):format(tostring(key)), 2)
+	end,
+})
+
+function Error.new(kind, extra)
+	return setmetatable({
+		kind = kind,
+		extra = extra,
+	}, Error)
+end
+
+function Error:__tostring()
+	return ("Error(%s: %s)"):format(self.kind, tostring(self.extra))
+end
+
+return Error

plugin/rbx_dom_lua/src/PropertyDescriptor.lua

@@ -0,0 +1,80 @@
+local Error = require(script.Parent.Error)
+local customProperties = require(script.Parent.customProperties)
+
+-- A wrapper around a property descriptor from the reflection database with some
+-- extra convenience methods.
+--
+-- The aim of this API is to facilitate looking up a property once, then reading
+-- from it or writing to it multiple times. It's also useful when a consumer
+-- wants to check additional constraints on the property before trying to use
+-- it, like scriptability.
+local PropertyDescriptor = {}
+PropertyDescriptor.__index = PropertyDescriptor
+
+local function get(container, key)
+	return container[key]
+end
+
+local function set(container, key, value)
+	container[key] = value
+end
+
+function PropertyDescriptor.fromRaw(data, className, propertyName)
+	return setmetatable({
+		scriptability = data.scriptability,
+		className = className,
+		name = propertyName,
+	}, PropertyDescriptor)
+end
+
+function PropertyDescriptor:read(instance)
+	if self.scriptability == "ReadWrite" or self.scriptability == "Read" then
+		local success, value = xpcall(get, debug.traceback, instance, self.name)
+
+		if success then
+			return success, value
+		else
+			return false, Error.new(Error.Kind.Roblox, value)
+		end
+	end
+
+	if self.scriptability == "Custom" then
+		local interface = customProperties[self.className][self.name]
+
+		return interface.read(instance, self.name)
+	end
+
+	if self.scriptability == "None" or self.scriptability == "Write" then
+		local fullName = ("%s.%s"):format(instance.className, self.name)
+
+		return false, Error.new(Error.Kind.PropertyNotReadable, fullName)
+	end
+
+	error(("Internal error: unexpected value of 'scriptability': %s"):format(tostring(self.scriptability)), 2)
+end
+
+function PropertyDescriptor:write(instance, value)
+	if self.scriptability == "ReadWrite" or self.scriptability == "Write" then
+		local success, err = xpcall(set, debug.traceback, instance, self.name, value)
+
+		if success then
+			return success
+		else
+			return false, Error.new(Error.Kind.Roblox, err)
+		end
+	end
+
+	if self.scriptability == "Custom" then
+		local interface = customProperties[self.className][self.name]
+
+		return interface.write(instance, self.name, value)
+	end
+
+	if self.scriptability == "None" or self.scriptability == "Read" then
+		local fullName = ("%s.%s"):format(instance.className, self.name)
+
+		return false, Error.new(Error.Kind.PropertyNotWritable, fullName)
+	end
+end
+
+return PropertyDescriptor

plugin/rbx_dom_lua/src/ReflectionDatabase/init.lua

@@ -0,0 +1,3 @@
+return {
+	classes = require(script.classes)
+}

plugin/rbx_dom_lua/src/base64.lua

@@ -0,0 +1,139 @@
+-- Thanks to Tiffany352 for this base64 implementation!
+
+local floor = math.floor
+local char = string.char
+
+local function encodeBase64(str)
+	local out = {}
+	local nOut = 0
+	local alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+	local strLen = #str
+
+	-- 3 octets become 4 hextets
+	for i = 1, strLen - 2, 3 do
+		local b1, b2, b3 = str:byte(i, i + 3)
+		local word = b3 + b2 * 256 + b1 * 256 * 256
+
+		local h4 = word % 64 + 1
+		word = floor(word / 64)
+		local h3 = word % 64 + 1
+		word = floor(word / 64)
+		local h2 = word % 64 + 1
+		word = floor(word / 64)
+		local h1 = word % 64 + 1
+
+		out[nOut + 1] = alphabet:sub(h1, h1)
+		out[nOut + 2] = alphabet:sub(h2, h2)
+		out[nOut + 3] = alphabet:sub(h3, h3)
+		out[nOut + 4] = alphabet:sub(h4, h4)
+		nOut = nOut + 4
+	end
+
+	local remainder = strLen % 3
+
+	if remainder == 2 then
+		-- 16 input bits -> 3 hextets (2 full, 1 partial)
+		local b1, b2 = str:byte(-2, -1)
+		-- partial is 4 bits long, leaving 2 bits of zero padding ->
+		-- offset = 4
+		local word = b2 * 4 + b1 * 4 * 256
+
+		local h3 = word % 64 + 1
+		word = floor(word / 64)
+		local h2 = word % 64 + 1
+		word = floor(word / 64)
+		local h1 = word % 64 + 1
+
+		out[nOut + 1] = alphabet:sub(h1, h1)
+		out[nOut + 2] = alphabet:sub(h2, h2)
+		out[nOut + 3] = alphabet:sub(h3, h3)
+		out[nOut + 4] = "="
+	elseif remainder == 1 then
+		-- 8 input bits -> 2 hextets (2 full, 1 partial)
+		local b1 = str:byte(-1, -1)
+		-- partial is 2 bits long, leaving 4 bits of zero padding ->
+		-- offset = 16
+		local word = b1 * 16
+
+		local h2 = word % 64 + 1
+		word = floor(word / 64)
+		local h1 = word % 64 + 1
+
+		out[nOut + 1] = alphabet:sub(h1, h1)
+		out[nOut + 2] = alphabet:sub(h2, h2)
+		out[nOut + 3] = "="
+		out[nOut + 4] = "="
+	end
+	-- if the remainder is 0, then no work is needed
+
+	return table.concat(out, "")
+end
+
+local function decodeBase64(str)
+	local out = {}
+	local nOut = 0
+	local alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
+	local strLen = #str
+	local acc = 0
+	local nAcc = 0
+
+	local alphabetLut = {}
+	for i = 1, #alphabet do
+		alphabetLut[alphabet:sub(i, i)] = i - 1
+	end
+
+	-- 4 hextets become 3 octets
+	for i = 1, strLen do
+		local ch = str:sub(i, i)
+		local byte = alphabetLut[ch]
+		if byte then
+			acc = acc * 64 + byte
+			nAcc = nAcc + 1
+		end
+
+		if nAcc == 4 then
+			local b3 = acc % 256
+			acc = floor(acc / 256)
+			local b2 = acc % 256
+			acc = floor(acc / 256)
+			local b1 = acc % 256
+
+			out[nOut + 1] = char(b1)
+			out[nOut + 2] = char(b2)
+			out[nOut + 3] = char(b3)
+			nOut = nOut + 3
+			nAcc = 0
+			acc = 0
+		end
+	end
+
+	if nAcc == 3 then
+		-- 3 hextets -> 16 bit output
+		acc = acc * 64
+		acc = floor(acc / 256)
+		local b2 = acc % 256
+		acc = floor(acc / 256)
+		local b1 = acc % 256
+
+		out[nOut + 1] = char(b1)
+		out[nOut + 2] = char(b2)
+	elseif nAcc == 2 then
+		-- 2 hextets -> 8 bit output
+		acc = acc * 64
+		acc = floor(acc / 256)
+		acc = acc * 64
+		acc = floor(acc / 256)
+		local b1 = acc % 256
+
+		out[nOut + 1] = char(b1)
+	elseif nAcc == 1 then
+		error("Base64 has invalid length")
+	end
+
+	return table.concat(out, "")
+end
+
+return {
+	decode = decodeBase64,
+	encode = encodeBase64,
+}

plugin/rbx_dom_lua/src/base64.spec.lua

@@ -0,0 +1,29 @@
+return function()
+	local base64 = require(script.Parent.base64)
+
+	it("should encode and decode", function()
+		local function try(str, expected)
+			local encoded = base64.encode(str)
+			expect(encoded).to.equal(expected)
+			expect(base64.decode(encoded)).to.equal(str)
+		end
+
+		try("Man", "TWFu")
+		try("Ma", "TWE=")
+		try("M", "TQ==")
+		try("ManM", "TWFuTQ==")
+		try(
+			[[Man is distinguished, not only by his reason, but by this ]]..
+			[[singular passion from other animals, which is a lust of the ]]..
+			[[mind, that by a perseverance of delight in the continued and ]]..
+			[[indefatigable generation of knowledge, exceeds the short ]]..
+			[[vehemence of any carnal pleasure.]],
+			[[TWFuIGlzIGRpc3Rpbmd1aXNoZWQsIG5vdCBvbmx5IGJ5IGhpcyByZWFzb24sI]]..
+			[[GJ1dCBieSB0aGlzIHNpbmd1bGFyIHBhc3Npb24gZnJvbSBvdGhlciBhbmltYW]]..
+			[[xzLCB3aGljaCBpcyBhIGx1c3Qgb2YgdGhlIG1pbmQsIHRoYXQgYnkgYSBwZXJ]]..
+			[[zZXZlcmFuY2Ugb2YgZGVsaWdodCBpbiB0aGUgY29udGludWVkIGFuZCBpbmRl]]..
+			[[ZmF0aWdhYmxlIGdlbmVyYXRpb24gb2Yga25vd2xlZGdlLCBleGNlZWRzIHRoZ]]..
+			[[SBzaG9ydCB2ZWhlbWVuY2Ugb2YgYW55IGNhcm5hbCBwbGVhc3VyZS4=]]
+		)
+	end)
+end

plugin/rbx_dom_lua/src/customProperties.lua

@@ -0,0 +1,47 @@
+local CollectionService = game:GetService("CollectionService")
+
+-- Defines how to read and write properties that aren't directly scriptable.
+--
+-- The reflection database refers to these as having scriptability = "Custom"
+return {
+	Instance = {
+		Tags = {
+			read = function(instance, key)
+				local tagList = CollectionService:GetTags(instance)
+
+				return true, table.concat(tagList, "\0")
+			end,
+			write = function(instance, key, value)
+				local existingTags = CollectionService:GetTags(instance)
+
+				local unseenTags = {}
+				for _, tag in ipairs(existingTags) do
+					unseenTags[tag] = true
+				end
+
+				local tagList = string.split(value, "\0")
+				for _, tag in ipairs(tagList) do
+					unseenTags[tag] = nil
+					CollectionService:AddTag(instance, tag)
+				end
+
+				for tag in pairs(unseenTags) do
+					CollectionService:RemoveTag(instance, tag)
+				end
+
+				return true
+			end,
+		},
+	},
+	LocalizationTable = {
+		Contents = {
+			read = function(instance, key)
+				return true, instance:GetContents()
+			end,
+			write = function(instance, key, value)
+				instance:SetContents(value)
+				return true
+			end,
+		},
+	},
+}

plugin/rbx_dom_lua/src/init.lua

@@ -0,0 +1,67 @@
+local ReflectionDatabase = require(script.ReflectionDatabase)
+local Error = require(script.Error)
+local PropertyDescriptor = require(script.PropertyDescriptor)
+
+local function findCanonicalPropertyDescriptor(className, propertyName)
+	local currentClassName = className
+
+	repeat
+		local currentClass = ReflectionDatabase.classes[currentClassName]
+
+		if currentClass == nil then
+			return currentClass
+		end
+
+		local propertyData = currentClass.properties[propertyName]
+		if propertyData ~= nil then
+			if propertyData.isCanonical then
+				return PropertyDescriptor.fromRaw(propertyData, currentClassName, propertyName)
+			end
+
+			if propertyData.canonicalName ~= nil then
+				return PropertyDescriptor.fromRaw(
+					currentClass.properties[propertyData.canonicalName],
+					currentClassName,
+					propertyData.canonicalName)
+			end
+
+			return nil
+		end
+
+		currentClassName = currentClass.superclass
+	until currentClassName == nil
+
+	return nil
+end
+
+local function readProperty(instance, propertyName)
+	local descriptor = findCanonicalPropertyDescriptor(instance.ClassName, propertyName)
+
+	if descriptor == nil then
+		local fullName = ("%s.%s"):format(instance.className, propertyName)
+
+		return false, Error.new(Error.Kind.UnknownProperty, fullName)
+	end
+
+	return descriptor:read(instance)
+end
+
+local function writeProperty(instance, propertyName, value)
+	local descriptor = findCanonicalPropertyDescriptor(instance.ClassName, propertyName)
+
+	if descriptor == nil then
+		local fullName = ("%s.%s"):format(instance.className, propertyName)
+
+		return false, Error.new(Error.Kind.UnknownProperty, fullName)
+	end
+
+	return descriptor:write(instance, value)
+end
+
+return {
+	readProperty = readProperty,
+	writeProperty = writeProperty,
+	findCanonicalPropertyDescriptor = findCanonicalPropertyDescriptor,
+	Error = Error,
+	EncodedValue = require(script.EncodedValue),
+}

plugin/rbx_dom_lua/src/init.spec.lua

@@ -0,0 +1,7 @@
+return function()
+	local RbxDom = require(script.Parent)
+
+	it("should load", function()
+		expect(RbxDom).to.be.ok()
+	end)
+end

plugin/rbx_dom_lua/test-place.project.json

@@ -0,0 +1,35 @@
+{
+  "name": "rbx_dom_lua test place",
+  "tree": {
+    "$className": "DataModel",
+    "ReplicatedStorage": {
+      "$className": "ReplicatedStorage",
+
+      "RbxDom": {
+        "$path": "src"
+      },
+      "TestEZ": {
+        "$path": "modules/testez/lib"
+      }
+    },
+    "ServerScriptService": {
+      "$className": "ServerScriptService",
+
+      "Run Tests": {
+        "$path": "test.server.lua"
+      }
+    },
+    "Players": {
+      "$className": "Players",
+      "$properties": {
+        "CharacterAutoLoads": false
+      }
+    },
+    "HttpService": {
+      "$className": "HttpService",
+      "$properties": {
+        "HttpEnabled": true
+      }
+    }
+  }
+}

plugin/rbx_dom_lua/test.server.lua

@@ -0,0 +1,7 @@
+local ReplicatedStorage = game:GetService("ReplicatedStorage")
+
+local LIB_ROOT = ReplicatedStorage.RbxDom
+
+local TestEZ = require(ReplicatedStorage.TestEZ)
+
+TestEZ.TestBootstrap:run({LIB_ROOT})

plugin/src/ApiContext.lua

@@ -158,19 +158,35 @@ end
 function ApiContext:write(patch)
 	local url = ("%s/api/write"):format(self.__baseUrl)
 
-	local body = {
-		sessionId = self.__sessionId,
-		removed = patch.removed,
-		updated = patch.updated,
-	}
+	local updated = {}
+	for _, update in ipairs(patch.updated) do
+		local fixedUpdate = {
+			id = update.id,
+			changedName = update.changedName,
+		}
+
+		if next(update.changedProperties) ~= nil then
+			fixedUpdate.changedProperties = update.changedProperties
+		end
+
+		table.insert(updated, fixedUpdate)
+	end
 
 	-- Only add the 'added' field if the table is non-empty, or else Roblox's
 	-- JSON implementation will turn the table into an array instead of an
 	-- object, causing API validation to fail.
+	local added
 	if next(patch.added) ~= nil then
-		body.added = patch.added
+		added = patch.added
 	end
 
+	local body = {
+		sessionId = self.__sessionId,
+		removed = patch.removed,
+		updated = updated,
+		added = added,
+	}
+
 	body = Http.jsonEncode(body)
 
 	return Http.post(url, body)
@@ -217,4 +233,19 @@ function ApiContext:retrieveMessages()
 		end)
 end
 
+function ApiContext:open(id)
+	local url = ("%s/api/open/%s"):format(self.__baseUrl, id)
+
+	return Http.post(url, "")
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(body)
+			if body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
+
+			return nil
+		end)
+end
+
 return ApiContext

plugin/src/Components/App.lua

@@ -17,6 +17,7 @@ local ConnectPanel = require(Plugin.Components.ConnectPanel)
 local ConnectingPanel = require(Plugin.Components.ConnectingPanel)
 local ConnectionActivePanel = require(Plugin.Components.ConnectionActivePanel)
 local ErrorPanel = require(Plugin.Components.ErrorPanel)
+local SettingsPanel = require(Plugin.Components.SettingsPanel)
 
 local e = Roact.createElement
 
@@ -61,6 +62,7 @@ local AppStatus = strict("AppStatus", {
 	Connecting = "Connecting",
 	Connected = "Connected",
 	Error = "Error",
+	Settings = "Settings",
 })
 
 local App = Roact.Component:extend("App")
@@ -73,10 +75,7 @@ function App:init()
 
 	self.signals = {}
 	self.serveSession = nil
-
-	self.displayedVersion = DevSettings:isEnabled()
-		and Config.codename
-		or Version.display(Config.version)
+	self.displayedVersion = Version.display(Config.version)
 
 	local toolbar = self.props.plugin:CreateToolbar("Rojo " .. self.displayedVersion)
 
@@ -108,12 +107,14 @@ function App:init()
 	end)
 end
 
-function App:startSession(address, port)
+function App:startSession(address, port, sessionOptions)
 	Log.trace("Starting new session")
 
 	local baseUrl = ("http://%s:%s"):format(address, port)
 	self.serveSession = ServeSession.new({
 		apiContext = ApiContext.new(baseUrl),
+		openScriptsExternally = sessionOptions.openScriptsExternally,
+		twoWaySync = sessionOptions.twoWaySync,
 	})
 
 	self.serveSession:onStatusChanged(function(status, details)
@@ -154,8 +155,13 @@ function App:render()
 	if self.state.appStatus == AppStatus.NotStarted then
 		children = {
 			ConnectPanel = e(ConnectPanel, {
-				startSession = function(address, port)
-					self:startSession(address, port)
+				startSession = function(address, port, settings)
+					self:startSession(address, port, settings)
+				end,
+				openSettings = function()
+					self:setState({
+						appStatus = AppStatus.Settings,
+					})
 				end,
 				cancel = function()
 					Log.trace("Canceling session configuration")
@@ -168,7 +174,7 @@ function App:render()
 		}
 	elseif self.state.appStatus == AppStatus.Connecting then
 		children = {
-			ConnectingPanel = Roact.createElement(ConnectingPanel),
+			ConnectingPanel = e(ConnectingPanel),
 		}
 	elseif self.state.appStatus == AppStatus.Connected then
 		children = {
@@ -186,9 +192,19 @@ function App:render()
 				end,
 			}),
 		}
+	elseif self.state.appStatus == AppStatus.Settings then
+		children = {
+			e(SettingsPanel, {
+				back = function()
+					self:setState({
+						appStatus = AppStatus.NotStarted,
+					})
+				end,
+			}),
+		}
 	elseif self.state.appStatus == AppStatus.Error then
 		children = {
-			ErrorPanel = Roact.createElement(ErrorPanel, {
+			ErrorPanel = e(ErrorPanel, {
 				errorMessage = self.state.errorMessage,
 				onDismiss = function()
 					self:setState({
@@ -199,7 +215,7 @@ function App:render()
 		}
 	end
 
-	return Roact.createElement(Roact.Portal, {
+	return e(Roact.Portal, {
 		target = self.dockWidget,
 	}, children)
 end

plugin/src/Components/Checkbox.lua

@@ -0,0 +1,39 @@
+local Rojo = script:FindFirstAncestor("Rojo")
+local Plugin = Rojo.Plugin
+
+local Roact = require(Rojo.Roact)
+
+local Theme = require(Plugin.Components.Theme)
+
+local e = Roact.createElement
+
+local function Checkbox(props)
+	local checked = props.checked
+	local layoutOrder = props.layoutOrder
+	local onChange = props.onChange
+
+	return Theme.with(function(theme)
+		return e("ImageButton", {
+			LayoutOrder = layoutOrder,
+			Size = UDim2.new(0, 20, 0, 20),
+			BorderSizePixel = 2,
+			BorderColor3 = theme.Text2,
+			BackgroundColor3 = theme.Background2,
+
+			[Roact.Event.Activated] = function()
+				onChange(not checked)
+			end,
+		}, {
+			Indicator = e("Frame", {
+				Size = UDim2.new(0, 18, 0, 18),
+				Position = UDim2.new(0.5, 0, 0.5, 0),
+				AnchorPoint = Vector2.new(0.5, 0.5),
+				BorderSizePixel = 0,
+				BackgroundColor3 = theme.Brand1,
+				BackgroundTransparency = checked and 0 or 1,
+			})
+		})
+	end)
+end
+
+return Checkbox

plugin/src/Components/ConnectPanel.lua

@@ -4,13 +4,14 @@ local Plugin = Rojo.Plugin
 local Roact = require(Rojo.Roact)
 
 local Config = require(Plugin.Config)
-local Theme = require(Plugin.Theme)
 
+local Theme = require(Plugin.Components.Theme)
 local Panel = require(Plugin.Components.Panel)
 local FitList = require(Plugin.Components.FitList)
 local FitText = require(Plugin.Components.FitText)
 local FormButton = require(Plugin.Components.FormButton)
 local FormTextInput = require(Plugin.Components.FormTextInput)
+local PluginSettings = require(Plugin.Components.PluginSettings)
 
 local e = Roact.createElement
 
@@ -25,137 +26,158 @@ end
 
 function ConnectPanel:render()
 	local startSession = self.props.startSession
+	local openSettings = self.props.openSettings
 
-	return e(Panel, nil, {
-		Layout = e("UIListLayout", {
-			SortOrder = Enum.SortOrder.LayoutOrder,
-			HorizontalAlignment = Enum.HorizontalAlignment.Center,
-			VerticalAlignment = Enum.VerticalAlignment.Center,
-		}),
-
-		Inputs = e(FitList, {
-			containerProps = {
-				BackgroundTransparency = 1,
-				LayoutOrder = 1,
-			},
-			layoutProps = {
-				FillDirection = Enum.FillDirection.Horizontal,
-				Padding = UDim.new(0, 8),
-			},
-			paddingProps = {
-				PaddingTop = UDim.new(0, 20),
-				PaddingBottom = UDim.new(0, 10),
-				PaddingLeft = UDim.new(0, 24),
-				PaddingRight = UDim.new(0, 24),
-			},
-		}, {
-			Address = e(FitList, {
-				containerProps = {
-					LayoutOrder = 1,
-					BackgroundTransparency = 1,
-				},
-				layoutProps = {
-					Padding = UDim.new(0, 4),
-				},
-			}, {
-				Label = e(FitText, {
-					Kind = "TextLabel",
-					LayoutOrder = 1,
-					BackgroundTransparency = 1,
-					TextXAlignment = Enum.TextXAlignment.Left,
-					Font = Theme.TitleFont,
-					TextSize = 20,
-					Text = "Address",
-					TextColor3 = Theme.PrimaryColor,
+	return Theme.with(function(theme)
+		return PluginSettings.with(function(settings)
+			return e(Panel, nil, {
+				Layout = e("UIListLayout", {
+					SortOrder = Enum.SortOrder.LayoutOrder,
+					HorizontalAlignment = Enum.HorizontalAlignment.Center,
+					VerticalAlignment = Enum.VerticalAlignment.Center,
 				}),
 
-				Input = e(FormTextInput, {
-					layoutOrder = 2,
-					width = UDim.new(0, 220),
-					value = self.state.address,
-					placeholderValue = Config.defaultHost,
-					onValueChange = function(newValue)
-						self:setState({
-							address = newValue,
-						})
-					end,
-				}),
-			}),
+				Inputs = e(FitList, {
+					containerProps = {
+						BackgroundTransparency = 1,
+						LayoutOrder = 1,
+					},
+					layoutProps = {
+						FillDirection = Enum.FillDirection.Horizontal,
+						Padding = UDim.new(0, 8),
+					},
+					paddingProps = {
+						PaddingTop = UDim.new(0, 20),
+						PaddingBottom = UDim.new(0, 10),
+						PaddingLeft = UDim.new(0, 24),
+						PaddingRight = UDim.new(0, 24),
+					},
+				}, {
+					Address = e(FitList, {
+						containerProps = {
+							LayoutOrder = 1,
+							BackgroundTransparency = 1,
+						},
+						layoutProps = {
+							Padding = UDim.new(0, 4),
+						},
+					}, {
+						Label = e(FitText, {
+							Kind = "TextLabel",
+							LayoutOrder = 1,
+							BackgroundTransparency = 1,
+							TextXAlignment = Enum.TextXAlignment.Left,
+							Font = theme.TitleFont,
+							TextSize = 20,
+							Text = "Address",
+							TextColor3 = theme.Text1,
+						}),
 
-			Port = e(FitList, {
-				containerProps = {
-					LayoutOrder = 2,
-					BackgroundTransparency = 1,
-				},
-				layoutProps = {
-					Padding = UDim.new(0, 4),
-				},
-			}, {
-				Label = e(FitText, {
-					Kind = "TextLabel",
-					LayoutOrder = 1,
-					BackgroundTransparency = 1,
-					TextXAlignment = Enum.TextXAlignment.Left,
-					Font = Theme.TitleFont,
-					TextSize = 20,
-					Text = "Port",
-					TextColor3 = Theme.PrimaryColor,
+						Input = e(FormTextInput, {
+							layoutOrder = 2,
+							width = UDim.new(0, 220),
+							value = self.state.address,
+							placeholderValue = Config.defaultHost,
+							onValueChange = function(newValue)
+								self:setState({
+									address = newValue,
+								})
+							end,
+						}),
+					}),
+
+					Port = e(FitList, {
+						containerProps = {
+							LayoutOrder = 2,
+							BackgroundTransparency = 1,
+						},
+						layoutProps = {
+							Padding = UDim.new(0, 4),
+						},
+					}, {
+						Label = e(FitText, {
+							Kind = "TextLabel",
+							LayoutOrder = 1,
+							BackgroundTransparency = 1,
+							TextXAlignment = Enum.TextXAlignment.Left,
+							Font = theme.TitleFont,
+							TextSize = 20,
+							Text = "Port",
+							TextColor3 = theme.Text1,
+						}),
+
+						Input = e(FormTextInput, {
+							layoutOrder = 2,
+							width = UDim.new(0, 80),
+							value = self.state.port,
+							placeholderValue = Config.defaultPort,
+							onValueChange = function(newValue)
+								self:setState({
+									port = newValue,
+								})
+							end,
+						}),
+					}),
 				}),
 
-				Input = e(FormTextInput, {
-					layoutOrder = 2,
-					width = UDim.new(0, 80),
-					value = self.state.port,
-					placeholderValue = Config.defaultPort,
-					onValueChange = function(newValue)
-						self:setState({
-							port = newValue,
-						})
-					end,
+				Buttons = e(FitList, {
+					fitAxes = "Y",
+					containerProps = {
+						BackgroundTransparency = 1,
+						LayoutOrder = 2,
+						Size = UDim2.new(1, 0, 0, 0),
+					},
+					layoutProps = {
+						FillDirection = Enum.FillDirection.Horizontal,
+						HorizontalAlignment = Enum.HorizontalAlignment.Right,
+						Padding = UDim.new(0, 8),
+					},
+					paddingProps = {
+						PaddingTop = UDim.new(0, 0),
+						PaddingBottom = UDim.new(0, 20),
+						PaddingLeft = UDim.new(0, 24),
+						PaddingRight = UDim.new(0, 24),
+					},
+				}, {
+					e(FormButton, {
+						layoutOrder = 1,
+						text = "Settings",
+						secondary = true,
+						onClick = function()
+							if openSettings ~= nil then
+								openSettings()
+							end
+						end,
+					}),
+
+					e(FormButton, {
+						layoutOrder = 2,
+						text = "Connect",
+						onClick = function()
+							if startSession ~= nil then
+								local address = self.state.address
+								if address:len() == 0 then
+									address = Config.defaultHost
+								end
+
+								local port = self.state.port
+								if port:len() == 0 then
+									port = Config.defaultPort
+								end
+
+								local sessionOptions = {
+									openScriptsExternally = settings:get("openScriptsExternally"),
+									twoWaySync = settings:get("twoWaySync"),
+								}
+
+								startSession(address, port, sessionOptions)
+							end
+						end,
+					}),
 				}),
-			}),
-		}),
-
-		Buttons = e(FitList, {
-			fitAxes = "Y",
-			containerProps = {
-				BackgroundTransparency = 1,
-				LayoutOrder = 2,
-				Size = UDim2.new(1, 0, 0, 0),
-			},
-			layoutProps = {
-				FillDirection = Enum.FillDirection.Horizontal,
-				HorizontalAlignment = Enum.HorizontalAlignment.Right,
-				Padding = UDim.new(0, 8),
-			},
-			paddingProps = {
-				PaddingTop = UDim.new(0, 0),
-				PaddingBottom = UDim.new(0, 20),
-				PaddingLeft = UDim.new(0, 24),
-				PaddingRight = UDim.new(0, 24),
-			},
-		}, {
-			e(FormButton, {
-				layoutOrder = 2,
-				text = "Connect",
-				onClick = function()
-					if startSession ~= nil then
-						local address = self.state.address
-						if address:len() == 0 then
-							address = Config.defaultHost
-						end
-
-						local port = self.state.port
-						if port:len() == 0 then
-							port = Config.defaultPort
-						end
-
-						startSession(address, port)
-					end
-				end,
-			}),
-		}),
-	})
+			})
+		end)
+	end)
 end
 
 return ConnectPanel

plugin/src/Components/ConnectingPanel.lua

@@ -2,8 +2,7 @@ local Roact = require(script:FindFirstAncestor("Rojo").Roact)
 
 local Plugin = script:FindFirstAncestor("Plugin")
 
-local Theme = require(Plugin.Theme)
-
+local Theme = require(Plugin.Components.Theme)
 local Panel = require(Plugin.Components.Panel)
 local FitText = require(Plugin.Components.FitText)
 
@@ -12,23 +11,25 @@ local e = Roact.createElement
 local ConnectingPanel = Roact.Component:extend("ConnectingPanel")
 
 function ConnectingPanel:render()
-	return e(Panel, nil, {
-		Layout = Roact.createElement("UIListLayout", {
-			HorizontalAlignment = Enum.HorizontalAlignment.Center,
-			VerticalAlignment = Enum.VerticalAlignment.Center,
-			SortOrder = Enum.SortOrder.LayoutOrder,
-			Padding = UDim.new(0, 8),
-		}),
+	return Theme.with(function(theme)
+		return e(Panel, nil, {
+			Layout = Roact.createElement("UIListLayout", {
+				HorizontalAlignment = Enum.HorizontalAlignment.Center,
+				VerticalAlignment = Enum.VerticalAlignment.Center,
+				SortOrder = Enum.SortOrder.LayoutOrder,
+				Padding = UDim.new(0, 8),
+			}),
 
-		Text = e(FitText, {
-			Padding = Vector2.new(12, 6),
-			Font = Theme.ButtonFont,
-			TextSize = 18,
-			Text = "Connecting...",
-			TextColor3 = Theme.PrimaryColor,
-			BackgroundTransparency = 1,
-		}),
-	})
+			Text = e(FitText, {
+				Padding = Vector2.new(12, 6),
+				Font = theme.ButtonFont,
+				TextSize = 18,
+				Text = "Connecting...",
+				TextColor3 = theme.Text1,
+				BackgroundTransparency = 1,
+			}),
+		})
+	end)
 end
 
 return ConnectingPanel

plugin/src/Components/ConnectionActivePanel.lua

@@ -2,8 +2,7 @@ local Roact = require(script:FindFirstAncestor("Rojo").Roact)
 
 local Plugin = script:FindFirstAncestor("Plugin")
 
-local Theme = require(Plugin.Theme)
-
+local Theme = require(Plugin.Components.Theme)
 local Panel = require(Plugin.Components.Panel)
 local FitText = require(Plugin.Components.FitText)
 local FormButton = require(Plugin.Components.FormButton)
@@ -15,32 +14,34 @@ local ConnectionActivePanel = Roact.Component:extend("ConnectionActivePanel")
 function ConnectionActivePanel:render()
 	local stopSession = self.props.stopSession
 
-	return e(Panel, nil, {
-		Layout = Roact.createElement("UIListLayout", {
-			HorizontalAlignment = Enum.HorizontalAlignment.Center,
-			VerticalAlignment = Enum.VerticalAlignment.Center,
-			SortOrder = Enum.SortOrder.LayoutOrder,
-			Padding = UDim.new(0, 8),
-		}),
+	return Theme.with(function(theme)
+		return e(Panel, nil, {
+			Layout = Roact.createElement("UIListLayout", {
+				HorizontalAlignment = Enum.HorizontalAlignment.Center,
+				VerticalAlignment = Enum.VerticalAlignment.Center,
+				SortOrder = Enum.SortOrder.LayoutOrder,
+				Padding = UDim.new(0, 8),
+			}),
 
-		Text = e(FitText, {
-			Padding = Vector2.new(12, 6),
-			Font = Theme.ButtonFont,
-			TextSize = 18,
-			Text = "Connected to Live-Sync Server",
-			TextColor3 = Theme.PrimaryColor,
-			BackgroundTransparency = 1,
-		}),
+			Text = e(FitText, {
+				Padding = Vector2.new(12, 6),
+				Font = theme.ButtonFont,
+				TextSize = 18,
+				Text = "Connected to Live-Sync Server",
+				TextColor3 = theme.Text1,
+				BackgroundTransparency = 1,
+			}),
 
-		DisconnectButton = e(FormButton, {
-			layoutOrder = 2,
-			text = "Disconnect",
-			secondary = true,
-			onClick = function()
-				stopSession()
-			end,
-		}),
-	})
+			DisconnectButton = e(FormButton, {
+				layoutOrder = 2,
+				text = "Disconnect",
+				secondary = true,
+				onClick = function()
+					stopSession()
+				end,
+			}),
+		})
+	end)
 end
 
 return ConnectionActivePanel

plugin/src/Components/ErrorPanel.lua

@@ -2,8 +2,7 @@ local Roact = require(script:FindFirstAncestor("Rojo").Roact)
 
 local Plugin = script:FindFirstAncestor("Plugin")
 
-local Theme = require(Plugin.Theme)
-
+local Theme = require(Plugin.Components.Theme)
 local Panel = require(Plugin.Components.Panel)
 local FitText = require(Plugin.Components.FitText)
 local FitScrollingFrame = require(Plugin.Components.FitScrollingFrame)
@@ -20,50 +19,52 @@ function ErrorPanel:render()
 	local errorMessage = self.props.errorMessage
 	local onDismiss = self.props.onDismiss
 
-	return e(Panel, nil, {
-		Layout = Roact.createElement("UIListLayout", {
-			HorizontalAlignment = Enum.HorizontalAlignment.Center,
-			VerticalAlignment = Enum.VerticalAlignment.Center,
-			SortOrder = Enum.SortOrder.LayoutOrder,
-			Padding = UDim.new(0, 8),
-		}),
-
-		ErrorContainer = e(FitScrollingFrame, {
-			containerProps = {
-				BackgroundTransparency = 1,
-				BorderSizePixel = 0,
-				Size = UDim2.new(1, -HOR_PADDING * 2, 1, -BUTTON_HEIGHT),
-				Position = UDim2.new(0, HOR_PADDING, 0, 0),
-				ScrollBarImageColor3 = Theme.PrimaryColor,
-				VerticalScrollBarInset = Enum.ScrollBarInset.ScrollBar,
-				ScrollingDirection = Enum.ScrollingDirection.Y,
-			},
-		}, {
-			Text = e(FitText, {
-				Size = UDim2.new(1, 0, 0, 0),
-
-				LayoutOrder = 1,
-				TextXAlignment = Enum.TextXAlignment.Left,
-				TextYAlignment = Enum.TextYAlignment.Top,
-				FitAxis = "Y",
-				Font = Theme.ButtonFont,
-				TextSize = 18,
-				Text = errorMessage,
-				TextWrap = true,
-				TextColor3 = Theme.PrimaryColor,
-				BackgroundTransparency = 1,
+	return Theme.with(function(theme)
+		return e(Panel, nil, {
+			Layout = Roact.createElement("UIListLayout", {
+				HorizontalAlignment = Enum.HorizontalAlignment.Center,
+				VerticalAlignment = Enum.VerticalAlignment.Center,
+				SortOrder = Enum.SortOrder.LayoutOrder,
+				Padding = UDim.new(0, 8),
 			}),
-		}),
 
-		DismissButton = e(FormButton, {
-			layoutOrder = 2,
-			text = "Dismiss",
-			secondary = true,
-			onClick = function()
-				onDismiss()
-			end,
-		}),
-	})
+			ErrorContainer = e(FitScrollingFrame, {
+				containerProps = {
+					BackgroundTransparency = 1,
+					BorderSizePixel = 0,
+					Size = UDim2.new(1, -HOR_PADDING * 2, 1, -BUTTON_HEIGHT),
+					Position = UDim2.new(0, HOR_PADDING, 0, 0),
+					ScrollBarImageColor3 = theme.Text1,
+					VerticalScrollBarInset = Enum.ScrollBarInset.ScrollBar,
+					ScrollingDirection = Enum.ScrollingDirection.Y,
+				},
+			}, {
+				Text = e(FitText, {
+					Size = UDim2.new(1, 0, 0, 0),
+
+					LayoutOrder = 1,
+					TextXAlignment = Enum.TextXAlignment.Left,
+					TextYAlignment = Enum.TextYAlignment.Top,
+					FitAxis = "Y",
+					Font = theme.ButtonFont,
+					TextSize = 18,
+					Text = errorMessage,
+					TextWrap = true,
+					TextColor3 = theme.Text1,
+					BackgroundTransparency = 1,
+				}),
+			}),
+
+			DismissButton = e(FormButton, {
+				layoutOrder = 2,
+				text = "Dismiss",
+				secondary = true,
+				onClick = function()
+					onDismiss()
+				end,
+			}),
+		})
+	end)
 end
 
 return ErrorPanel

plugin/src/Components/FormButton.lua

@@ -4,7 +4,7 @@ local Plugin = Rojo.Plugin
 local Roact = require(Rojo.Roact)
 
 local Assets = require(Plugin.Assets)
-local Theme = require(Plugin.Theme)
+local Theme = require(Plugin.Components.Theme)
 local FitList = require(Plugin.Components.FitList)
 local FitText = require(Plugin.Components.FitText)
 
@@ -20,43 +20,45 @@ local function FormButton(props)
 	local textColor
 	local backgroundColor
 
-	if props.secondary then
-		textColor = Theme.AccentColor
-		backgroundColor = Theme.SecondaryColor
-	else
-		textColor = Theme.SecondaryColor
-		backgroundColor = Theme.AccentColor
-	end
+	return Theme.with(function(theme)
+		if props.secondary then
+			textColor = theme.Brand1
+			backgroundColor = theme.Background2
+		else
+			textColor = theme.TextOnAccent
+			backgroundColor = theme.Brand1
+		end
 
-	return e(FitList, {
-		containerKind = "ImageButton",
-		containerProps = {
-			LayoutOrder = layoutOrder,
-			BackgroundTransparency = 1,
-			Image = RoundBox.asset,
-			ImageRectOffset = RoundBox.offset,
-			ImageRectSize = RoundBox.size,
-			SliceCenter = RoundBox.center,
-			ScaleType = Enum.ScaleType.Slice,
-			ImageColor3 = backgroundColor,
+		return e(FitList, {
+			containerKind = "ImageButton",
+			containerProps = {
+				LayoutOrder = layoutOrder,
+				BackgroundTransparency = 1,
+				Image = RoundBox.asset,
+				ImageRectOffset = RoundBox.offset,
+				ImageRectSize = RoundBox.size,
+				SliceCenter = RoundBox.center,
+				ScaleType = Enum.ScaleType.Slice,
+				ImageColor3 = backgroundColor,
 
-			[Roact.Event.Activated] = function()
-				if onClick ~= nil then
-					onClick()
-				end
-			end,
-		},
-	}, {
-		Text = e(FitText, {
-			Kind = "TextLabel",
-			Text = text,
-			TextSize = 18,
-			TextColor3 = textColor,
-			Font = Theme.ButtonFont,
-			Padding = Vector2.new(16, 8),
-			BackgroundTransparency = 1,
-		}),
-	})
+				[Roact.Event.Activated] = function()
+					if onClick ~= nil then
+						onClick()
+					end
+				end,
+			},
+		}, {
+			Text = e(FitText, {
+				Kind = "TextLabel",
+				Text = text,
+				TextSize = 18,
+				TextColor3 = textColor,
+				Font = theme.ButtonFont,
+				Padding = Vector2.new(16, 8),
+				BackgroundTransparency = 1,
+			}),
+		})
+	end)
 end
 
 return FormButton

plugin/src/Components/FormTextInput.lua

@@ -4,7 +4,7 @@ local Plugin = Rojo.Plugin
 local Roact = require(Rojo.Roact)
 
 local Assets = require(Plugin.Assets)
-local Theme = require(Plugin.Theme)
+local Theme = require(Plugin.Components.Theme)
 
 local e = Roact.createElement
 
@@ -35,46 +35,48 @@ function FormTextInput:render()
 		shownPlaceholder = placeholderValue
 	end
 
-	return e("ImageLabel", {
-		LayoutOrder = layoutOrder,
-		Image = RoundBox.asset,
-		ImageRectOffset = RoundBox.offset,
-		ImageRectSize = RoundBox.size,
-		ScaleType = Enum.ScaleType.Slice,
-		SliceCenter = RoundBox.center,
-		ImageColor3 = Theme.SecondaryColor,
-		Size = UDim2.new(width.Scale, width.Offset, 0, TEXT_SIZE + PADDING * 2),
-		BackgroundTransparency = 1,
-	}, {
-		InputInner = e("TextBox", {
+	return Theme.with(function(theme)
+		return e("ImageLabel", {
+			LayoutOrder = layoutOrder,
+			Image = RoundBox.asset,
+			ImageRectOffset = RoundBox.offset,
+			ImageRectSize = RoundBox.size,
+			ScaleType = Enum.ScaleType.Slice,
+			SliceCenter = RoundBox.center,
+			ImageColor3 = theme.Background2,
+			Size = UDim2.new(width.Scale, width.Offset, 0, TEXT_SIZE + PADDING * 2),
 			BackgroundTransparency = 1,
-			Size = UDim2.new(1, -PADDING * 2, 1, -PADDING * 2),
-			Position = UDim2.new(0.5, 0, 0.5, 0),
-			AnchorPoint = Vector2.new(0.5, 0.5),
-			Font = Theme.InputFont,
-			ClearTextOnFocus = false,
-			TextXAlignment = Enum.TextXAlignment.Center,
-			TextSize = TEXT_SIZE,
-			Text = value,
-			PlaceholderText = shownPlaceholder,
-			PlaceholderColor3 = Theme.LightTextColor,
-			TextColor3 = Theme.PrimaryColor,
+		}, {
+			InputInner = e("TextBox", {
+				BackgroundTransparency = 1,
+				Size = UDim2.new(1, -PADDING * 2, 1, -PADDING * 2),
+				Position = UDim2.new(0.5, 0, 0.5, 0),
+				AnchorPoint = Vector2.new(0.5, 0.5),
+				Font = theme.InputFont,
+				ClearTextOnFocus = false,
+				TextXAlignment = Enum.TextXAlignment.Center,
+				TextSize = TEXT_SIZE,
+				Text = value,
+				PlaceholderText = shownPlaceholder,
+				PlaceholderColor3 = theme.Text2,
+				TextColor3 = theme.Text1,
 
-			[Roact.Change.Text] = function(rbx)
-				onValueChange(rbx.Text)
-			end,
-			[Roact.Event.Focused] = function()
-				self:setState({
-					focused = true,
-				})
-			end,
-			[Roact.Event.FocusLost] = function()
-				self:setState({
-					focused = false,
-				})
-			end,
-		}),
-	})
+				[Roact.Change.Text] = function(rbx)
+					onValueChange(rbx.Text)
+				end,
+				[Roact.Event.Focused] = function()
+					self:setState({
+						focused = true,
+					})
+				end,
+				[Roact.Event.FocusLost] = function()
+					self:setState({
+						focused = false,
+					})
+				end,
+			}),
+		})
+	end)
 end
 
 return FormTextInput

plugin/src/Components/Panel.lua

@@ -3,6 +3,7 @@ local Roact = require(script:FindFirstAncestor("Rojo").Roact)
 local Plugin = script:FindFirstAncestor("Plugin")
 
 local RojoFooter = require(Plugin.Components.RojoFooter)
+local Theme = require(Plugin.Components.Theme)
 
 local e = Roact.createElement
 
@@ -13,22 +14,25 @@ function Panel:init()
 end
 
 function Panel:render()
-	return e("Frame", {
-		Size = UDim2.new(1, 0, 1, 0),
-		BackgroundTransparency = 1,
-	}, {
-		Layout = Roact.createElement("UIListLayout", {
-			HorizontalAlignment = Enum.HorizontalAlignment.Center,
-			SortOrder = Enum.SortOrder.LayoutOrder,
-		}),
+	return Theme.with(function(theme)
+		return e("Frame", {
+			Size = UDim2.new(1, 0, 1, 0),
+			BackgroundColor3 = theme.Background1,
+			BorderSizePixel = 1,
+		}, {
+			Layout = Roact.createElement("UIListLayout", {
+				HorizontalAlignment = Enum.HorizontalAlignment.Center,
+				SortOrder = Enum.SortOrder.LayoutOrder,
+			}),
 
-		Body = e("Frame", {
-			Size = UDim2.new(0, 360, 1, -32),
-			BackgroundTransparency = 1,
-		}, self.props[Roact.Children]),
+			Body = e("Frame", {
+				Size = UDim2.new(0, 360, 1, -32),
+				BackgroundTransparency = 1,
+			}, self.props[Roact.Children]),
 
-		Footer = e(RojoFooter),
-	})
+			Footer = e(RojoFooter),
+		})
+	end)
 end
 
 return Panel

plugin/src/Components/PluginSettings.lua

@@ -0,0 +1,121 @@
+--[[
+	Persistent plugin settings that can be accessed via Roact context.
+]]
+
+local Rojo = script:FindFirstAncestor("Rojo")
+
+local Roact = require(Rojo.Roact)
+
+local defaultSettings = {
+	openScriptsExternally = false,
+	twoWaySync = false,
+}
+
+local Settings = {}
+Settings.__index = Settings
+
+function Settings.fromPlugin(plugin)
+	local values = {}
+
+	for name, defaultValue in pairs(defaultSettings) do
+		local savedValue = plugin:GetSetting("Rojo_" .. name)
+
+		if savedValue == nil then
+			plugin:SetSetting("Rojo_" .. name, defaultValue)
+			values[name] = defaultValue
+		else
+			values[name] = savedValue
+		end
+	end
+
+	return setmetatable({
+		__values = values,
+		__plugin = plugin,
+		__updateListeners = {},
+	}, Settings)
+end
+
+function Settings:get(name)
+	if defaultSettings[name] == nil then
+		error("Invalid setings name " .. tostring(name), 2)
+	end
+
+	return self.__values[name]
+end
+
+function Settings:set(name, value)
+	self.__plugin:SetSetting("Rojo_" .. name, value)
+	self.__values[name] = value
+
+	for callback in pairs(self.__updateListeners) do
+		callback(name, value)
+	end
+end
+
+function Settings:onUpdate(newCallback)
+	local newListeners = {}
+	for callback in pairs(self.__updateListeners) do
+		newListeners[callback] = true
+	end
+
+	newListeners[newCallback] = true
+	self.__updateListeners = newListeners
+
+	return function()
+		local newListeners = {}
+		for callback in pairs(self.__updateListeners) do
+			if callback ~= newCallback then
+				newListeners[callback] = true
+			end
+		end
+
+		self.__updateListeners = newListeners
+	end
+end
+
+local Context = Roact.createContext(nil)
+
+local StudioProvider = Roact.Component:extend("StudioProvider")
+
+function StudioProvider:init()
+	self.settings = Settings.fromPlugin(self.props.plugin)
+end
+
+function StudioProvider:render()
+	return Roact.createElement(Context.Provider, {
+		value = self.settings,
+	}, self.props[Roact.Children])
+end
+
+local InternalConsumer = Roact.Component:extend("InternalConsumer")
+
+function InternalConsumer:render()
+	return self.props.render(self.props.settings)
+end
+
+function InternalConsumer:didMount()
+	self.disconnect = self.props.settings:onUpdate(function()
+		-- Trigger a dummy state update to update the settings consumer.
+		self:setState({})
+	end)
+end
+
+function InternalConsumer:willUnmount()
+	self.disconnect()
+end
+
+local function with(callback)
+	return Roact.createElement(Context.Consumer, {
+		render = function(settings)
+			return Roact.createElement(InternalConsumer, {
+				settings = settings,
+				render = callback,
+			})
+		end,
+	})
+end
+
+return {
+	StudioProvider = StudioProvider,
+	with = with,
+}

plugin/src/Components/RojoFooter.lua

@@ -6,7 +6,7 @@ local Roact = require(Rojo.Roact)
 local Config = require(Plugin.Config)
 local Version = require(Plugin.Version)
 local Assets = require(Plugin.Assets)
-local Theme = require(Plugin.Theme)
+local Theme = require(Plugin.Components.Theme)
 
 local e = Roact.createElement
 
@@ -18,50 +18,53 @@ function RojoFooter:init()
 end
 
 function RojoFooter:render()
-	return e("Frame", {
-		LayoutOrder = 3,
-		Size = UDim2.new(1, 0, 0, 32),
-		BackgroundColor3 = Theme.SecondaryColor,
-		BorderSizePixel = 0,
-	}, {
-		Padding = e("UIPadding", {
-			PaddingTop = UDim.new(0, 4),
-			PaddingBottom = UDim.new(0, 4),
-			PaddingLeft = UDim.new(0, 8),
-			PaddingRight = UDim.new(0, 8),
-		}),
-
-		LogoContainer = e("Frame", {
-			BackgroundTransparency = 1,
-
-			Size = UDim2.new(0, 0, 0, 32),
+	return Theme.with(function(theme)
+		return e("Frame", {
+			LayoutOrder = 3,
+			Size = UDim2.new(1, 0, 0, 32),
+			BackgroundColor3 = theme.Background2,
+			BorderSizePixel = 0,
+			ZIndex = 2,
 		}, {
-			Logo = e("ImageLabel", {
-				Image = Assets.Images.Logo,
-				Size = UDim2.new(0, 80, 0, 40),
-				ScaleType = Enum.ScaleType.Fit,
-				BackgroundTransparency = 1,
-				Position = UDim2.new(0, 0, 1, -10),
-				AnchorPoint = Vector2.new(0, 1),
+			Padding = e("UIPadding", {
+				PaddingTop = UDim.new(0, 4),
+				PaddingBottom = UDim.new(0, 4),
+				PaddingLeft = UDim.new(0, 8),
+				PaddingRight = UDim.new(0, 8),
 			}),
-		}),
 
-		Version = e("TextLabel", {
-			Position = UDim2.new(1, 0, 0, 0),
-			Size = UDim2.new(0, 0, 1, 0),
-			AnchorPoint = Vector2.new(1, 0),
-			Font = Theme.TitleFont,
-			TextSize = 18,
-			Text = Version.display(Config.version),
-			TextXAlignment = Enum.TextXAlignment.Right,
-			TextColor3 = Theme.LightTextColor,
-			BackgroundTransparency = 1,
+			LogoContainer = e("Frame", {
+				BackgroundTransparency = 1,
 
-			[Roact.Change.AbsoluteSize] = function(rbx)
-				self.setFooterVersionSize(rbx.AbsoluteSize)
-			end,
-		}),
-	})
+				Size = UDim2.new(0, 0, 0, 32),
+			}, {
+				Logo = e("ImageLabel", {
+					Image = Assets.Images.Logo,
+					Size = UDim2.new(0, 80, 0, 40),
+					ScaleType = Enum.ScaleType.Fit,
+					BackgroundTransparency = 1,
+					Position = UDim2.new(0, 0, 1, -10),
+					AnchorPoint = Vector2.new(0, 1),
+				}),
+			}),
+
+			Version = e("TextLabel", {
+				Position = UDim2.new(1, 0, 0, 0),
+				Size = UDim2.new(0, 0, 1, 0),
+				AnchorPoint = Vector2.new(1, 0),
+				Font = theme.TitleFont,
+				TextSize = 18,
+				Text = Version.display(Config.version),
+				TextXAlignment = Enum.TextXAlignment.Right,
+				TextColor3 = theme.Text2,
+				BackgroundTransparency = 1,
+
+				[Roact.Change.AbsoluteSize] = function(rbx)
+					self.setFooterVersionSize(rbx.AbsoluteSize)
+				end,
+			}),
+		})
+	end)
 end
 
 return RojoFooter

plugin/src/Components/SettingsPanel.lua

@@ -0,0 +1,119 @@
+local Roact = require(script:FindFirstAncestor("Rojo").Roact)
+
+local Plugin = script:FindFirstAncestor("Plugin")
+
+local Checkbox = require(Plugin.Components.Checkbox)
+local FitList = require(Plugin.Components.FitList)
+local FitText = require(Plugin.Components.FitText)
+local FormButton = require(Plugin.Components.FormButton)
+local Panel = require(Plugin.Components.Panel)
+local PluginSettings = require(Plugin.Components.PluginSettings)
+local Theme = require(Plugin.Components.Theme)
+
+local e = Roact.createElement
+
+local SettingsPanel = Roact.Component:extend("SettingsPanel")
+
+function SettingsPanel:render()
+	local back = self.props.back
+
+	return Theme.with(function(theme)
+		return PluginSettings.with(function(settings)
+			return e(Panel, nil, {
+				Layout = Roact.createElement("UIListLayout", {
+					HorizontalAlignment = Enum.HorizontalAlignment.Center,
+					VerticalAlignment = Enum.VerticalAlignment.Center,
+					SortOrder = Enum.SortOrder.LayoutOrder,
+					Padding = UDim.new(0, 16),
+				}),
+
+				OpenScriptsExternally = e(FitList, {
+					containerProps = {
+						LayoutOrder = 1,
+						BackgroundTransparency = 1,
+					},
+					layoutProps = {
+						Padding = UDim.new(0, 4),
+						FillDirection = Enum.FillDirection.Horizontal,
+						HorizontalAlignment = Enum.HorizontalAlignment.Left,
+						VerticalAlignment = Enum.VerticalAlignment.Center,
+					},
+				}, {
+					Label = e(FitText, {
+						Kind = "TextLabel",
+						LayoutOrder = 1,
+						BackgroundTransparency = 1,
+						TextXAlignment = Enum.TextXAlignment.Left,
+						Font = theme.MainFont,
+						TextSize = 16,
+						Text = "Open Scripts Externally",
+						TextColor3 = theme.Text1,
+					}),
+
+					Padding = e("Frame", {
+						Size = UDim2.new(0, 8, 0, 0),
+						BackgroundTransparency = 1,
+						LayoutOrder = 2,
+					}),
+
+					Input = e(Checkbox, {
+						layoutOrder = 3,
+						checked = settings:get("openScriptsExternally"),
+						onChange = function(newValue)
+							settings:set("openScriptsExternally", not settings:get("openScriptsExternally"))
+						end,
+					}),
+				}),
+
+				TwoWaySync = e(FitList, {
+					containerProps = {
+						LayoutOrder = 2,
+						BackgroundTransparency = 1,
+					},
+					layoutProps = {
+						Padding = UDim.new(0, 4),
+						FillDirection = Enum.FillDirection.Horizontal,
+						HorizontalAlignment = Enum.HorizontalAlignment.Left,
+						VerticalAlignment = Enum.VerticalAlignment.Center,
+					},
+				}, {
+					Label = e(FitText, {
+						Kind = "TextLabel",
+						LayoutOrder = 1,
+						BackgroundTransparency = 1,
+						TextXAlignment = Enum.TextXAlignment.Left,
+						Font = theme.MainFont,
+						TextSize = 16,
+						Text = "Two-Way Sync (Experimental!)",
+						TextColor3 = theme.Text1,
+					}),
+
+					Padding = e("Frame", {
+						Size = UDim2.new(0, 8, 0, 0),
+						BackgroundTransparency = 1,
+						LayoutOrder = 2,
+					}),
+
+					Input = e(Checkbox, {
+						layoutOrder = 3,
+						checked = settings:get("twoWaySync"),
+						onChange = function(newValue)
+							settings:set("twoWaySync", not settings:get("twoWaySync"))
+						end,
+					}),
+				}),
+
+				BackButton = e(FormButton, {
+					layoutOrder = 4,
+					text = "Okay",
+					secondary = true,
+					onClick = function()
+						back()
+					end,
+				}),
+			})
+		end)
+	end)
+end
+
+return SettingsPanel

plugin/src/Components/Theme.lua

@@ -0,0 +1,113 @@
+--[[
+	Theming system taking advantage of Roact's new context API.
+
+	Doesn't use colors provided by Studio and instead just branches on theme
+	name. This isn't exactly best practice.
+]]
+
+-- Studio does not exist outside Roblox Studio, so we'll lazily initialize it
+-- when possible.
+local _Studio
+local function getStudio()
+	if _Studio == nil then
+		_Studio = settings():GetService("Studio")
+	end
+
+	return _Studio
+end
+
+local Rojo = script:FindFirstAncestor("Rojo")
+
+local Roact = require(Rojo.Roact)
+local Log = require(Rojo.Log)
+
+local strict = require(script.Parent.Parent.strict)
+
+local lightTheme = strict("Theme", {
+	ButtonFont = Enum.Font.GothamSemibold,
+	InputFont = Enum.Font.Code,
+	TitleFont = Enum.Font.GothamBold,
+	MainFont = Enum.Font.Gotham,
+
+	Brand1 = Color3.fromRGB(225, 56, 53),
+
+	Text1 = Color3.fromRGB(64, 64, 64),
+	Text2 = Color3.fromRGB(160, 160, 160),
+	TextOnAccent = Color3.fromRGB(235, 235, 235),
+
+	Background1 = Color3.fromRGB(255, 255, 255),
+	Background2 = Color3.fromRGB(235, 235, 235),
+})
+
+local darkTheme = strict("Theme", {
+	ButtonFont = Enum.Font.GothamSemibold,
+	InputFont = Enum.Font.Code,
+	TitleFont = Enum.Font.GothamBold,
+	MainFont = Enum.Font.Gotham,
+
+	Brand1 = Color3.fromRGB(225, 56, 53),
+
+	Text1 = Color3.fromRGB(235, 235, 235),
+	Text2 = Color3.fromRGB(200, 200, 200),
+	TextOnAccent = Color3.fromRGB(235, 235, 235),
+
+	Background1 = Color3.fromRGB(48, 48, 48),
+	Background2 = Color3.fromRGB(64, 64, 64),
+})
+
+local Context = Roact.createContext(lightTheme)
+
+local StudioProvider = Roact.Component:extend("StudioProvider")
+
+-- Pull the current theme from Roblox Studio and update state with it.
+function StudioProvider:updateTheme()
+	local studioTheme = getStudio().Theme
+
+	if studioTheme.Name == "Light" then
+		self:setState({
+			theme = lightTheme,
+		})
+	elseif studioTheme.Name == "Dark" then
+		self:setState({
+			theme = darkTheme,
+		})
+	else
+		Log.warn("Unexpected theme '{}'' -- falling back to light theme!", studioTheme.Name)
+
+		self:setState({
+			theme = lightTheme,
+		})
+	end
+end
+
+function StudioProvider:init()
+	self:updateTheme()
+end
+
+function StudioProvider:render()
+	return Roact.createElement(Context.Provider, {
+		value = self.state.theme,
+	}, self.props[Roact.Children])
+end
+
+function StudioProvider:didMount()
+	self.connection = getStudio().ThemeChanged:Connect(function()
+		self:updateTheme()
+	end)
+end
+
+function StudioProvider:willUnmount()
+	self.connection:Disconnect()
+end
+
+local function with(callback)
+	return Roact.createElement(Context.Consumer, {
+		render = callback,
+	})
+end
+
+return {
+	StudioProvider = StudioProvider,
+	Consumer = Context.Consumer,
+	with = with,
+}

plugin/src/Config.lua

@@ -5,8 +5,8 @@ local isDevBuild = script.Parent.Parent:FindFirstChild("ROJO_DEV_BUILD") ~= nil
 return strict("Config", {
 	isDevBuild = isDevBuild,
 	codename = "Epiphany",
-	version = {0, 6, 0, "-alpha.1"},
-	expectedServerVersionString = "0.6.0 or newer",
+	version = {6, 0, 0, "-rc.3"},
+	expectedServerVersionString = "6.0 or newer",
 	protocolVersion = 3,
 	defaultHost = "localhost",
 	defaultPort = 34872,

plugin/src/DevSettings.lua

@@ -25,14 +25,6 @@ local VALUES = {
 			[Environment.Test] = true,
 		},
 	},
-	UnstableTwoWaySync = {
-		type = "BoolValue",
-		values = {
-			[Environment.User] = false,
-			[Environment.Dev] = false,
-			[Environment.Test] = false,
-		},
-	},
 }
 
 local CONTAINER_NAME = "RojoDevSettings" .. Config.codename
@@ -140,10 +132,6 @@ function DevSettings:shouldTypecheck()
 	return getValue("TypecheckingEnabled")
 end
 
-function DevSettings:twoWaySyncEnabled()
-	return getValue("UnstableTwoWaySync")
-end
-
 function _G.ROJO_DEV_CREATE()
 	DevSettings:createDevSettings()
 end

plugin/src/InstanceMap.lua

@@ -11,15 +11,38 @@ InstanceMap.__index = InstanceMap
 
 function InstanceMap.new(onInstanceChanged)
 	local self = {
+		-- A map from IDs to instances.
 		fromIds = {},
+
+		-- A map from instances to IDs.
 		fromInstances = {},
+
+		-- A set of all instances that updates should be paused for. This set
+		-- should generally be empty, and will be filled by pauseInstance
+		-- temporarily.
+		pausedUpdateInstances = {},
+
+		-- A map from instances to a signal or list of signals connected to it.
 		instancesToSignal = {},
+
+		-- Callback that's invoked whenever an instance is changed and it was
+		-- not paused.
 		onInstanceChanged = onInstanceChanged,
 	}
 
 	return setmetatable(self, InstanceMap)
 end
 
+function InstanceMap:size()
+	local size = 0
+
+	for _ in pairs(self.fromIds) do
+		size = size + 1
+	end
+
+	return size
+end
+
 --[[
 	Disconnect all connections and release all instance references.
 ]]
@@ -56,6 +79,9 @@ function InstanceMap:__fmtDebug(output)
 end
 
 function InstanceMap:insert(id, instance)
+	self:removeId(id)
+	self:removeInstance(instance)
+
 	self.fromIds[id] = instance
 	self.fromInstances[instance] = id
 	self:__connectSignals(instance)
@@ -68,8 +94,6 @@ function InstanceMap:removeId(id)
 		self:__disconnectSignals(instance)
 		self.fromIds[id] = nil
 		self.fromInstances[instance] = nil
-	else
-		Log.warn("Attempted to remove nonexistant ID {}", id)
 	end
 end
 
@@ -80,8 +104,6 @@ function InstanceMap:removeInstance(instance)
 	if id ~= nil then
 		self.fromInstances[instance] = nil
 		self.fromIds[id] = nil
-	else
-		Log.warn("Attempted to remove nonexistant instance {}", instance)
 	end
 end
 
@@ -89,10 +111,14 @@ function InstanceMap:destroyInstance(instance)
 	local id = self.fromInstances[instance]
 
 	if id ~= nil then
-		self:destroyId(id)
-	else
-		Log.warn("Attempted to destroy untracked instance {}", instance)
+		self:removeId(id)
 	end
+
+	for _, descendantInstance in ipairs(instance:GetDescendants()) do
+		self:removeInstance(descendantInstance)
+	end
+
+	instance:Destroy()
 end
 
 function InstanceMap:destroyId(id)
@@ -100,21 +126,37 @@ function InstanceMap:destroyId(id)
 	self:removeId(id)
 
 	if instance ~= nil then
-		local descendantsToDestroy = {}
-
-		for otherInstance in pairs(self.fromInstances) do
-			if otherInstance:IsDescendantOf(instance) then
-				table.insert(descendantsToDestroy, otherInstance)
-			end
-		end
-
-		for _, otherInstance in ipairs(descendantsToDestroy) do
-			self:removeInstance(otherInstance)
+		for _, descendantInstance in ipairs(instance:GetDescendants()) do
+			self:removeInstance(descendantInstance)
 		end
 
 		instance:Destroy()
+	end
+end
+
+--[[
+	Pause updates for an instance momentarily and invoke a callback.
+
+	If the callback throws an error, InstanceMap will still be kept in a
+	consistent state.
+]]
+function InstanceMap:pauseInstance(instance, callback)
+	local id = self.fromInstances[instance]
+
+	-- If we don't know about this instance, ignore it and do not invoke the
+	-- callback.
+	if id == nil then
+		return
+	end
+
+	self.pausedUpdateInstances[instance] = true
+	local success, result = xpcall(callback, debug.traceback)
+	self.pausedUpdateInstances[instance] = false
+
+	if success then
+		return result
 	else
-		Log.warn("Attempted to destroy nonexistant ID {}", id)
+		error(result, 2)
 	end
 end
 
@@ -133,6 +175,10 @@ function InstanceMap:__connectSignals(instance)
 			instance:GetPropertyChangedSignal("Value"):Connect(function()
 				self:__maybeFireInstanceChanged(instance, "Value")
 			end),
+
+			instance:GetPropertyChangedSignal("Parent"):Connect(function()
+				self:__maybeFireInstanceChanged(instance, "Parent")
+			end),
 		}
 
 		self.instancesToSignal[instance] = signals
@@ -146,9 +192,15 @@ end
 function InstanceMap:__maybeFireInstanceChanged(instance, propertyName)
 	Log.trace("{}.{} changed", instance:GetFullName(), propertyName)
 
-	if self.onInstanceChanged ~= nil then
-		self.onInstanceChanged(instance, propertyName)
+	if self.pausedUpdateInstances[instance] then
+		return
 	end
+
+	if self.onInstanceChanged == nil then
+		return
+	end
+
+	self.onInstanceChanged(instance, propertyName)
 end
 
 function InstanceMap:__disconnectSignals(instance)

plugin/src/PatchSet.lua

@@ -0,0 +1,184 @@
+--[[
+	Methods to operate on either a patch created by the hydrate method, or a
+	patch returned from the API.
+]]
+
+local t = require(script.Parent.Parent.t)
+
+local Types = require(script.Parent.Types)
+
+local PatchSet = {}
+
+PatchSet.validate = t.interface({
+	removed = t.array(t.union(Types.RbxId, t.Instance)),
+	added = t.map(Types.RbxId, Types.ApiInstance),
+	updated = t.array(Types.ApiInstanceUpdate),
+})
+
+--[[
+	Create a new, empty PatchSet.
+]]
+function PatchSet.newEmpty()
+	return {
+		removed = {},
+		added = {},
+		updated = {},
+	}
+end
+
+--[[
+	Tells whether the given PatchSet is empty.
+]]
+function PatchSet.isEmpty(patchSet)
+	return next(patchSet.removed) == nil and
+		next(patchSet.added) == nil and
+		next(patchSet.updated) == nil
+end
+
+--[[
+	Tells whether the given PatchSet has any remove operations.
+]]
+function PatchSet.hasRemoves(patchSet)
+	return next(patchSet.removed) ~= nil
+end
+
+--[[
+	Tells whether the given PatchSet has any add operations.
+]]
+function PatchSet.hasAdditions(patchSet)
+	return next(patchSet.added) ~= nil
+end
+
+--[[
+	Tells whether the given PatchSet has any update operations.
+]]
+function PatchSet.hasUpdates(patchSet)
+	return next(patchSet.updated) ~= nil
+end
+
+--[[
+	Merge multiple PatchSet objects into the given PatchSet.
+]]
+function PatchSet.assign(target, ...)
+	for i = 1, select("#", ...) do
+		local sourcePatch = select(i, ...)
+
+		for _, removed in ipairs(sourcePatch.removed) do
+			table.insert(target.removed, removed)
+		end
+
+		for id, added in pairs(sourcePatch.added) do
+			target.added[id] = added
+		end
+
+		for _, update in ipairs(sourcePatch.updated) do
+			table.insert(target.updated, update)
+		end
+	end
+
+	return target
+end
+
+--[[
+	Create a list of human-readable statements summarizing the contents of this
+	patch, intended to be displayed to users.
+]]
+function PatchSet.humanSummary(instanceMap, patchSet)
+	local statements = {}
+
+	for _, idOrInstance in ipairs(patchSet.removed) do
+		local instance, id
+
+		if type(idOrInstance) == "string" then
+			id = idOrInstance
+			instance = instanceMap.fromIds[id]
+		else
+			instance = idOrInstance
+			id = instanceMap.fromInstances[instance]
+		end
+
+		if instance ~= nil then
+			table.insert(statements, string.format("- Delete instance %s", instance:GetFullName()))
+		else
+			table.insert(statements, string.format("- Delete instance with ID %s", id))
+		end
+	end
+
+	local additionsMentioned = {}
+
+	local function addAllDescendents(virtualInstance)
+		additionsMentioned[virtualInstance.Id] = true
+
+		for _, childId in ipairs(virtualInstance.Children) do
+			addAllDescendents(patchSet.added[childId])
+		end
+	end
+
+	for id, addition in pairs(patchSet.added) do
+		if additionsMentioned[id] then
+			continue
+		end
+
+		local virtualInstance = addition
+		while true do
+			if virtualInstance.Parent == nil then
+				break
+			end
+
+			local virtualParent = patchSet.added[virtualInstance.Parent]
+			if virtualParent == nil then
+				break
+			end
+
+			virtualInstance = virtualParent
+		end
+
+		local parentDisplayName = "nil (how strange!)"
+		if virtualInstance.Parent ~= nil then
+			local parent = instanceMap.fromIds[virtualInstance.Parent]
+			if parent ~= nil then
+				parentDisplayName = parent:GetFullName()
+			end
+		end
+
+		table.insert(statements, string.format(
+			"- Add instance %q (ClassName %q) to %s",
+			virtualInstance.Name, virtualInstance.ClassName, parentDisplayName))
+	end
+
+	for _, update in ipairs(patchSet.updated) do
+		local updatedProperties = {}
+
+		if update.changedMetadata ~= nil then
+			table.insert(updatedProperties, "Rojo's Metadata")
+		end
+
+		if update.changedName ~= nil then
+			table.insert(updatedProperties, "Name")
+		end
+
+		if update.changedClassName ~= nil then
+			table.insert(updatedProperties, "ClassName")
+		end
+
+		for name in pairs(update.changedProperties) do
+			table.insert(updatedProperties, name)
+		end
+
+		local instance = instanceMap.fromIds[update.id]
+		local displayName
+		if instance ~= nil then
+			displayName = instance:GetFullName()
+		else
+			displayName = "[unknown instance]"
+		end
+
+		table.insert(statements, string.format(
+			"- Update properties on %s: %s",
+			displayName, table.concat(updatedProperties, ",")))
+	end
+
+	return table.concat(statements, "\n")
+end
+
+return PatchSet

plugin/src/Reconciler.lua

@@ -1,401 +0,0 @@
---[[
-	This module defines the meat of the Rojo plugin and how it manages tracking
-	and mutating the Roblox DOM.
-]]
-
-local RbxDom = require(script.Parent.Parent.RbxDom)
-local t = require(script.Parent.Parent.t)
-local Log = require(script.Parent.Parent.Log)
-
-local Types = require(script.Parent.Types)
-local invariant = require(script.Parent.invariant)
-local getCanonicalProperty = require(script.Parent.getCanonicalProperty)
-local setCanonicalProperty = require(script.Parent.setCanonicalProperty)
-
---[[
-	This interface represents either a patch created by the hydrate method, or a
-	patch returned from the API.
-
-	This type should be a subset of Types.ApiInstanceUpdate.
-]]
-local IPatch = t.interface({
-	removed = t.array(t.union(Types.RbxId, t.Instance)),
-	added = t.map(Types.RbxId, Types.ApiInstance),
-	updated = t.array(Types.ApiInstanceUpdate),
-})
-
---[[
-	Attempt to safely set the parent of an instance.
-
-	This function will always succeed, even if the actual set failed. This is
-	important for some types like services that will throw even if their current
-	parent is already set to the requested parent.
-
-	TODO: See if we can eliminate this by being more nuanced with property
-	assignment?
-]]
-local function safeSetParent(instance, newParent)
-	pcall(function()
-		instance.Parent = newParent
-	end)
-end
-
---[[
-	Similar to setting Parent, some instances really don't like being renamed.
-
-	TODO: Should we be throwing away these results or can we be more careful?
-]]
-local function safeSetName(instance, name)
-	pcall(function()
-		instance.Name = name
-	end)
-end
-
-local Reconciler = {}
-Reconciler.__index = Reconciler
-
-function Reconciler.new(instanceMap)
-	local self = {
-		-- Tracks all of the instances known by the reconciler by ID.
-		__instanceMap = instanceMap,
-	}
-
-	return setmetatable(self, Reconciler)
-end
-
---[[
-	See Reconciler:__hydrateInternal().
-]]
-function Reconciler:hydrate(apiInstances, id, instance)
-	local hydratePatch = {
-		removed = {},
-		added = {},
-		updated = {},
-	}
-
-	self:__hydrateInternal(apiInstances, id, instance, hydratePatch)
-
-	return hydratePatch
-end
-
---[[
-	Applies a patch to the Roblox DOM using the reconciler's internal state.
-
-	TODO: This function might only apply some of the patch in the future and
-	require content negotiation with the Rojo server to handle types that aren't
-	editable by scripts.
-]]
-local applyPatchSchema = Types.ifEnabled(t.tuple(
-	IPatch
-))
-function Reconciler:applyPatch(patch)
-	assert(applyPatchSchema(patch))
-
-	for _, removedIdOrInstance in ipairs(patch.removed) do
-		local removedInstance
-
-		if Types.RbxId(removedIdOrInstance) then
-			-- If this value is an ID, it's assumed to be an instance that the
-			-- Rojo server knows about.
-			removedInstance = self.__instanceMap.fromIds[removedIdOrInstance]
-			self.__instanceMap:removeId(removedIdOrInstance)
-		end
-
-		-- If this entry was an ID that we didn't know about, removedInstance
-		-- will be nil, which we guard against in case of minor tree desync.
-		if removedInstance ~= nil then
-			-- Ensure that if any descendants are tracked by Rojo, that we
-			-- properly un-track them.
-			for _, descendantInstance in ipairs(removedInstance:GetDescendants()) do
-				self.__instanceMap:removeInstance(descendantInstance)
-			end
-
-			removedInstance:Destroy()
-		end
-	end
-
-	-- TODO: This loop assumes that apiInstance.ParentId is never nil. The Rojo
-	-- plugin can't create a new top-level DataModel anyways, so this should
-	-- only be violated in cases that are already erroneous.
-	for id, apiInstance in pairs(patch.added) do
-		if self.__instanceMap.fromIds[id] == nil then
-			-- Find the first ancestor of this instance that is marked for an
-			-- addition.
-			--
-			-- This helps us make sure we only reify each instance once, and we
-			-- start from the top.
-			while patch.added[apiInstance.Parent] ~= nil do
-				id = apiInstance.Parent
-				apiInstance = patch.added[id]
-			end
-
-			local parentInstance = self.__instanceMap.fromIds[apiInstance.Parent]
-
-			if parentInstance == nil then
-				invariant(
-					"Cannot add an instance from a patch that has no parent.\nInstance {} with parent {}.\nState: {:#?}",
-					id,
-					apiInstance.Parent,
-					self.__instanceMap
-				)
-			end
-
-			self:__reifyInstance(patch.added, id, parentInstance)
-		end
-	end
-
-	for _, update in ipairs(patch.updated) do
-		local instance = self.__instanceMap.fromIds[update.id]
-
-		if instance == nil then
-			invariant(
-				"Cannot update an instance that does not exist in the reconciler's state.\nInstance {}\nState: {:#?}",
-				update.id,
-				self.__instanceMap
-			)
-		end
-
-		if update.changedClassName ~= nil then
-			error("TODO: Support changing class name by destroying + recreating instance.")
-		end
-
-		if update.changedName ~= nil then
-			instance.Name = update.changedName
-		end
-
-		if update.changedMetadata ~= nil then
-			print("TODO: Support changing metadata, if necessary.")
-		end
-
-		if update.changedProperties ~= nil then
-			for propertyName, propertyValue in pairs(update.changedProperties) do
-				-- TODO: Gracefully handle this error instead?
-				assert(setCanonicalProperty(instance, propertyName, self:__decodeApiValue(propertyValue)))
-			end
-		end
-	end
-end
-
---[[
-	Transforms a value into one that can be sent over the network back to the
-	Rojo server.
-
-	This operation can fail, and so it returns bool, value.
-]]
-function Reconciler:encodeApiValue(value)
-	if typeof(value) == "string" then
-		return true, {
-			Type = "String",
-			Value = value,
-		}
-	end
-
-	return false
-end
-
---[[
-	Transforms a value encoded by rbx_dom_weak on the server side into a value
-	usable by Rojo's reconciler, potentially using RbxDom.
-]]
-function Reconciler:__decodeApiValue(apiValue)
-	assert(Types.ApiValue(apiValue))
-
-	-- Refs are represented as IDs in the same space that Rojo's protocol uses.
-	if apiValue.Type == "Ref" then
-		-- TODO: This ref could be pointing at an instance we haven't created
-		-- yet!
-
-		return self.__instanceMap.fromIds[apiValue.Value]
-	end
-
-	local success, decodedValue = RbxDom.EncodedValue.decode(apiValue)
-
-	if not success then
-		error(decodedValue, 2)
-	end
-
-	return decodedValue
-end
-
---[[
-	Constructs an instance from an ApiInstance without any of its children.
-]]
-local reifySingleInstanceSchema = Types.ifEnabled(t.tuple(
-	Types.ApiInstance
-))
-function Reconciler:__reifySingleInstance(apiInstance)
-	assert(reifySingleInstanceSchema(apiInstance))
-
-	-- Instance.new can fail if we're passing in something that can't be
-	-- created, like a service, something enabled with a feature flag, or
-	-- something that requires higher security than we have.
-	local ok, instance = pcall(Instance.new, apiInstance.ClassName)
-	if not ok then
-		return false, instance
-	end
-
-	-- TODO: When can setting Name fail here?
-	safeSetName(instance, apiInstance.Name)
-
-	for key, value in pairs(apiInstance.Properties) do
-		setCanonicalProperty(instance, key, self:__decodeApiValue(value))
-	end
-
-	return true, instance
-end
-
---[[
-	Construct an instance and all of its descendants, parent it to the given
-	instance, and insert it into the reconciler's internal state.
-]]
-local reifyInstanceSchema = Types.ifEnabled(t.tuple(
-	t.map(Types.RbxId, Types.VirtualInstance),
-	Types.RbxId,
-	t.Instance
-))
-function Reconciler:__reifyInstance(apiInstances, id, parentInstance)
-	assert(reifyInstanceSchema(apiInstances, id, parentInstance))
-
-	local apiInstance = apiInstances[id]
-	local ok, instance = self:__reifySingleInstance(apiInstance)
-
-	-- TODO: Propagate this error upward to handle it elsewhere?
-	if not ok then
-		error(("Couldn't create an instance of type %q, a child of %s"):format(
-			apiInstance.ClassName,
-			parentInstance:GetFullName()
-		))
-	end
-
-	self.__instanceMap:insert(id, instance)
-
-	for _, childId in ipairs(apiInstance.Children) do
-		self:__reifyInstance(apiInstances, childId, instance)
-	end
-
-	safeSetParent(instance, parentInstance)
-
-	return instance
-end
-
---[[
-	Populates the reconciler's internal state, maps IDs to instances that the
-	Rojo plugin knows about, and generates a patch that would update the Roblox
-	tree to match Rojo's view of the tree.
-]]
-local hydrateSchema = Types.ifEnabled(t.tuple(
-	t.map(Types.RbxId, Types.VirtualInstance),
-	Types.RbxId,
-	t.Instance,
-	IPatch
-))
-function Reconciler:__hydrateInternal(apiInstances, id, instance, hydratePatch)
-	assert(hydrateSchema(apiInstances, id, instance, hydratePatch))
-
-	self.__instanceMap:insert(id, instance)
-
-	local apiInstance = apiInstances[id]
-
-	local function markIdAdded(id)
-		local apiInstance = apiInstances[id]
-		hydratePatch.added[id] = apiInstance
-
-		for _, childId in ipairs(apiInstance.Children) do
-			markIdAdded(childId)
-		end
-	end
-
-	local changedName = nil
-	local changedProperties = {}
-
-	if apiInstance.Name ~= instance.Name then
-		changedName = apiInstance.Name
-	end
-
-	for propertyName, virtualValue in pairs(apiInstance.Properties) do
-		local success, existingValue = getCanonicalProperty(instance, propertyName)
-
-		if success then
-			local decodedValue = self:__decodeApiValue(virtualValue)
-
-			if existingValue ~= decodedValue then
-				changedProperties[propertyName] = virtualValue
-			end
-		end
-	end
-
-	-- If any properties differed from the virtual instance we read, add it to
-	-- the hydrate patch so that we can catch up.
-	if changedName ~= nil or next(changedProperties) ~= nil then
-		table.insert(hydratePatch.updated, {
-			id = id,
-			changedName = changedName,
-			changedClassName = nil,
-			changedProperties = changedProperties,
-			changedMetadata = nil,
-		})
-	end
-
-	local existingChildren = instance:GetChildren()
-
-	-- For each existing child, we'll track whether it's been paired with an
-	-- instance that the Rojo server knows about.
-	local isExistingChildVisited = {}
-	for i = 1, #existingChildren do
-		isExistingChildVisited[i] = false
-	end
-
-	for _, childId in ipairs(apiInstance.Children) do
-		local apiChild = apiInstances[childId]
-
-		local childInstance
-
-		for childIndex, instance in ipairs(existingChildren) do
-			if not isExistingChildVisited[childIndex] then
-				-- We guard accessing Name and ClassName in order to avoid
-				-- tripping over children of DataModel that Rojo won't have
-				-- permissions to access at all.
-				local ok, name, className = pcall(function()
-					return instance.Name, instance.ClassName
-				end)
-
-				-- This rule is very conservative and could be loosened in the
-				-- future, or more heuristics could be introduced.
-				if ok and name == apiChild.Name and className == apiChild.ClassName then
-					childInstance = instance
-					isExistingChildVisited[childIndex] = true
-					break
-				end
-			end
-		end
-
-		if childInstance ~= nil then
-			-- We found an instance that matches the instance from the API, yay!
-			self:__hydrateInternal(apiInstances, childId, childInstance, hydratePatch)
-		else
-			markIdAdded(childId)
-		end
-	end
-
-	-- Any unvisited children at this point aren't known by Rojo and we can
-	-- destroy them unless the user has explicitly asked us to preserve children
-	-- of this instance.
-	local shouldClearUnknown = self:__shouldClearUnknownChildren(apiInstance)
-	if shouldClearUnknown then
-		for childIndex, visited in ipairs(isExistingChildVisited) do
-			if not visited then
-				table.insert(hydratePatch.removed, existingChildren[childIndex])
-			end
-		end
-	end
-end
-
-function Reconciler:__shouldClearUnknownChildren(apiInstance)
-	if apiInstance.Metadata ~= nil then
-		return not apiInstance.Metadata.ignoreUnknownInstances
-	else
-		return true
-	end
-end
-
-return Reconciler

plugin/src/Reconciler/Error.lua

@@ -0,0 +1,37 @@
+--[[
+	Defines the errors that can be returned by the reconciler.
+]]
+
+local Fmt = require(script.Parent.Parent.Parent.Fmt)
+
+local Error = {}
+
+local function makeVariant(name)
+	Error[name] = setmetatable({}, {
+		__tostring = function()
+			return "Error." .. name
+		end,
+	})
+end
+
+makeVariant("CannotCreateInstance")
+makeVariant("CannotDecodeValue")
+makeVariant("LackingPropertyPermissions")
+makeVariant("OtherPropertyError")
+makeVariant("RefDidNotExist")
+makeVariant("UnknownProperty")
+makeVariant("UnreadableProperty")
+makeVariant("UnwritableProperty")
+
+function Error.new(kind, details)
+	return setmetatable({
+		kind = kind,
+		details = details,
+	}, Error)
+end
+
+function Error:__tostring()
+	return Fmt.fmt("Error({}): {:#?}", self.kind, self.details)
+end
+
+return Error

plugin/src/Reconciler/applyPatch.lua

@@ -0,0 +1,200 @@
+--[[
+	Apply a patch to the DOM. Returns any portions of the patch that weren't
+	possible to apply.
+
+	Patches can come from the server or be generated by the client.
+]]
+
+local Log = require(script.Parent.Parent.Parent.Log)
+
+local PatchSet = require(script.Parent.Parent.PatchSet)
+local Types = require(script.Parent.Parent.Types)
+local invariant = require(script.Parent.Parent.invariant)
+
+local decodeValue = require(script.Parent.decodeValue)
+local reify = require(script.Parent.reify)
+local setProperty = require(script.Parent.setProperty)
+
+local function applyPatch(instanceMap, patch)
+	-- Tracks any portions of the patch that could not be applied to the DOM.
+	local unappliedPatch = PatchSet.newEmpty()
+
+	for _, removedIdOrInstance in ipairs(patch.removed) do
+		if Types.RbxId(removedIdOrInstance) then
+			instanceMap:destroyId(removedIdOrInstance)
+		else
+			instanceMap:destroyInstance(removedIdOrInstance)
+		end
+	end
+
+	for id, virtualInstance in pairs(patch.added) do
+		if instanceMap.fromIds[id] ~= nil then
+			-- This instance already exists. We might've already added it in a
+			-- previous iteration of this loop, or maybe this patch was not
+			-- supposed to list this instance.
+			--
+			-- It's probably fine, right?
+			continue
+		end
+
+		-- Find the first ancestor of this instance that is marked for an
+		-- addition.
+		--
+		-- This helps us make sure we only reify each instance once, and we
+		-- start from the top.
+		while patch.added[virtualInstance.Parent] ~= nil do
+			id = virtualInstance.Parent
+			virtualInstance = patch.added[id]
+		end
+
+		local parentInstance = instanceMap.fromIds[virtualInstance.Parent]
+
+		if parentInstance == nil then
+			-- This would be peculiar. If you create an instance with no
+			-- parent, were you supposed to create it at all?
+			invariant(
+				"Cannot add an instance from a patch that has no parent.\nInstance {} with parent {}.\nState: {:#?}",
+				id,
+				virtualInstance.Parent,
+				instanceMap
+			)
+		end
+
+		local failedToReify = reify(instanceMap, patch.added, id, parentInstance)
+
+		if not PatchSet.isEmpty(failedToReify) then
+			Log.debug("Failed to reify as part of applying a patch: {}", failedToReify)
+			PatchSet.assign(unappliedPatch, failedToReify)
+		end
+	end
+
+	for _, update in ipairs(patch.updated) do
+		local instance = instanceMap.fromIds[update.id]
+
+		if instance == nil then
+			-- We can't update an instance that doesn't exist.
+			table.insert(unappliedPatch.updated, update)
+			continue
+		end
+
+		-- Track any part of this update that could not be applied.
+		local unappliedUpdate = {
+			id = update.id,
+			changedProperties = {},
+		}
+		local partiallyApplied = false
+
+		-- If the instance's className changed, we have a bumpy ride ahead while
+		-- we recreate this instance and move all of its children into the new
+		-- version atomically...ish.
+		if update.changedClassName ~= nil then
+			-- If the instance's name also changed, we'll do it here, since this
+			-- branch will skip the rest of the loop iteration.
+			local newName = update.changedName or instance.Name
+
+			-- TODO: When changing between instances that have similar sets of
+			-- properties, like between an ImageLabel and an ImageButton, we
+			-- should preserve all of the properties that are shared between the
+			-- two classes unless they're changed as part of this patch. This is
+			-- similar to how "class changer" Studio plugins work.
+			--
+			-- For now, we'll only apply properties that are mentioned in this
+			-- update. Patches with changedClassName set only occur in specific
+			-- circumstances, usually between Folder and ModuleScript instances.
+			-- While this may result in some issues, like not preserving the
+			-- "Archived" property, a robust solution is sufficiently
+			-- complicated that we're pushing it off for now.
+			local newProperties = update.changedProperties
+
+			-- If the instance's ClassName changed, we'll kick into reify to
+			-- create this instance. We'll handle moving all of children between
+			-- the instances after the new one is created.
+			local mockVirtualInstance = {
+				Id = update.id,
+				Name = newName,
+				ClassName = update.changedClassName,
+				Properties = newProperties,
+				Children = {},
+			}
+
+			local mockAdded = {
+				[update.id] = mockVirtualInstance,
+			}
+
+			local failedToReify = reify(instanceMap, mockAdded, update.id, instance.Parent)
+
+			local newInstance = instanceMap.fromIds[update.id]
+
+			-- Some parts of reify may have failed, but this is not necessarily
+			-- critical. If the instance wasn't recreated or has the wrong Name,
+			-- we'll consider our attempt a failure.
+			if instance == newInstance or newInstance.Name ~= newName then
+				table.insert(unappliedPatch.updated, update)
+				continue
+			end
+
+			-- Here are the non-critical failures. We know that the instance
+			-- succeeded in creating and that assigning Name did not fail, but
+			-- other property assignments might've failed.
+			if not PatchSet.isEmpty(failedToReify) then
+				PatchSet.assign(unappliedPatch, failedToReify)
+			end
+
+			-- Watch out, this is the scary part! Move all of the children of
+			-- instance into newInstance.
+			--
+			-- TODO: If this fails part way through, should we move everything
+			-- back? For now, we assume that moving things will not fail.
+			for _, child in ipairs(instance:GetChildren()) do
+				child.Parent = newInstance
+			end
+
+			-- See you later, original instance.
+			--
+			-- TODO: Can this fail? Some kinds of instance may not appreciate
+			-- being destroyed, like services.
+			instance:Destroy()
+
+			-- This completes your rebuilding a plane mid-flight safety
+			-- instruction. Please sit back, relax, and enjoy your flight.
+			continue
+		end
+
+		if update.changedName ~= nil then
+			instance.Name = update.changedName
+		end
+
+		if update.changedMetadata ~= nil then
+			-- TODO: Support changing metadata. This will become necessary when
+			-- Rojo persistently tracks metadata for each instance in order to
+			-- remove extra instances.
+			unappliedUpdate.changedMetadata = update.changedMetadata
+			partiallyApplied = true
+		end
+
+		if update.changedProperties ~= nil then
+			for propertyName, propertyValue in pairs(update.changedProperties) do
+				local ok, decodedValue = decodeValue(propertyValue, instanceMap)
+				if not ok then
+					unappliedUpdate.changedProperties[propertyName] = propertyValue
+					partiallyApplied = true
+					continue
+				end
+
+				local ok = setProperty(instance, propertyName, decodedValue)
+				if not ok then
+					unappliedUpdate.changedProperties[propertyName] = propertyValue
+					partiallyApplied = true
+				end
+			end
+		end
+
+		if partiallyApplied then
+			table.insert(unappliedPatch.updated, unappliedUpdate)
+		end
+	end
+
+	return unappliedPatch
+end
+
+return applyPatch

plugin/src/Reconciler/applyPatch.spec.lua

@@ -0,0 +1,198 @@
+return function()
+	local applyPatch = require(script.Parent.applyPatch)
+
+	local InstanceMap = require(script.Parent.Parent.InstanceMap)
+	local PatchSet = require(script.Parent.Parent.PatchSet)
+
+	local dummy = Instance.new("Folder")
+	local function wasDestroyed(instance)
+		-- If an instance was destroyed, its parent property is locked.
+		local ok = pcall(function()
+			local oldParent = instance.Parent
+			instance.Parent = dummy
+			instance.Parent = oldParent
+		end)
+
+		return not ok
+	end
+
+	it("should return an empty patch if given an empty patch", function()
+		local patch = applyPatch(InstanceMap.new(), PatchSet.newEmpty())
+		assert(PatchSet.isEmpty(patch), "expected remaining patch to be empty")
+	end)
+
+	it("should destroy instances listed for remove", function()
+		local root = Instance.new("Folder")
+
+		local child = Instance.new("Folder")
+		child.Name = "Child"
+		child.Parent = root
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("ROOT", root)
+		instanceMap:insert("CHILD", child)
+
+		local patch = PatchSet.newEmpty()
+		table.insert(patch.removed, child)
+
+		local unapplied = applyPatch(instanceMap, patch)
+		assert(PatchSet.isEmpty(unapplied), "expected remaining patch to be empty")
+
+		assert(not wasDestroyed(root), "expected root to be left alone")
+		assert(wasDestroyed(child), "expected child to be destroyed")
+
+		instanceMap:stop()
+	end)
+
+	it("should destroy IDs listed for remove", function()
+		local root = Instance.new("Folder")
+
+		local child = Instance.new("Folder")
+		child.Name = "Child"
+		child.Parent = root
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("ROOT", root)
+		instanceMap:insert("CHILD", child)
+
+		local patch = PatchSet.newEmpty()
+		table.insert(patch.removed, "CHILD")
+
+		local unapplied = applyPatch(instanceMap, patch)
+		assert(PatchSet.isEmpty(unapplied), "expected remaining patch to be empty")
+		expect(instanceMap:size()).to.equal(1)
+
+		assert(not wasDestroyed(root), "expected root to be left alone")
+		assert(wasDestroyed(child), "expected child to be destroyed")
+
+		instanceMap:stop()
+	end)
+
+	it("should add instances to the DOM", function()
+		-- Many of the details of this functionality are instead covered by
+		-- tests on reify, not here.
+
+		local root = Instance.new("Folder")
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("ROOT", root)
+
+		local patch = PatchSet.newEmpty()
+		patch.added["CHILD"] = {
+			Id = "CHILD",
+			ClassName = "Model",
+			Name = "Child",
+			Parent = "ROOT",
+			Children = {"GRANDCHILD"},
+			Properties = {},
+		}
+
+		patch.added["GRANDCHILD"]  = {
+			Id = "GRANDCHILD",
+			ClassName = "Part",
+			Name = "Grandchild",
+			Parent = "CHILD",
+			Children = {},
+			Properties = {},
+		}
+
+		local unapplied = applyPatch(instanceMap, patch)
+		assert(PatchSet.isEmpty(unapplied), "expected remaining patch to be empty")
+		expect(instanceMap:size()).to.equal(3)
+
+		local child = root:FindFirstChild("Child")
+		expect(child).to.be.ok()
+		expect(child.ClassName).to.equal("Model")
+		expect(child).to.equal(instanceMap.fromIds["CHILD"])
+
+		local grandchild = child:FindFirstChild("Grandchild")
+		expect(grandchild).to.be.ok()
+		expect(grandchild.ClassName).to.equal("Part")
+		expect(grandchild).to.equal(instanceMap.fromIds["GRANDCHILD"])
+	end)
+
+	it("should return unapplied additions when instances cannot be created", function()
+		local root = Instance.new("Folder")
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("ROOT", root)
+
+		local patch = PatchSet.newEmpty()
+		patch.added["OOPSIE"] = {
+			Id = "OOPSIE",
+			-- Hopefully Roblox never makes an instance with this ClassName.
+			ClassName = "UH OH",
+			Name = "FUBAR",
+			Parent = "ROOT",
+			Children = {},
+			Properties = {},
+		}
+
+		local unapplied = applyPatch(instanceMap, patch)
+		expect(unapplied.added["OOPSIE"]).to.equal(patch.added["OOPSIE"])
+		expect(instanceMap:size()).to.equal(1)
+		expect(#root:GetChildren()).to.equal(0)
+	end)
+
+	it("should apply property changes to instances", function()
+		local value = Instance.new("StringValue")
+		value.Value = "HELLO"
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("VALUE", value)
+
+		local patch = PatchSet.newEmpty()
+		table.insert(patch.updated, {
+			id = "VALUE",
+			changedProperties = {
+				Value = {
+					Type = "String",
+					Value = "WORLD",
+				},
+			},
+		})
+
+		local unapplied = applyPatch(instanceMap, patch)
+		assert(PatchSet.isEmpty(unapplied), "expected remaining patch to be empty")
+		expect(value.Value).to.equal("WORLD")
+	end)
+
+	it("should recreate instances when changedClassName is set, preserving children", function()
+		local root = Instance.new("Folder")
+		root.Name = "Initial Root Name"
+
+		local child = Instance.new("Folder")
+		child.Name = "Child"
+		child.Parent = root
+
+		local instanceMap = InstanceMap.new()
+		instanceMap:insert("ROOT", root)
+		instanceMap:insert("CHILD", child)
+
+		local patch = PatchSet.newEmpty()
+		table.insert(patch.updated, {
+			id = "ROOT",
+			changedName = "Updated Root Name",
+			changedClassName = "StringValue",
+			changedProperties = {
+				Value = {
+					Type = "String",
+					Value = "I am Root",
+				},
+			},
+		})
+
+		local unapplied = applyPatch(instanceMap, patch)
+		assert(PatchSet.isEmpty(unapplied), "expected remaining patch to be empty")
+
+		local newRoot = instanceMap.fromIds["ROOT"]
+		assert(newRoot ~= root, "expected instance to be recreated")
+		expect(newRoot.ClassName).to.equal("StringValue")
+		expect(newRoot.Name).to.equal("Updated Root Name")
+		expect(newRoot.Value).to.equal("I am Root")
+
+		local newChild = newRoot:FindFirstChild("Child")
+		assert(newChild ~= nil, "expected child to be present")
+		assert(newChild == child, "expected child to be preserved")
+	end)
+end

plugin/src/Reconciler/decodeValue.lua

@@ -0,0 +1,39 @@
+--[[
+	Transforms a value encoded by rbx_dom_weak on the server side into a value
+	usable by Rojo's reconciler, potentially using RbxDom.
+]]
+
+local RbxDom = require(script.Parent.Parent.Parent.RbxDom)
+local Error = require(script.Parent.Error)
+
+local function decodeValue(virtualValue, instanceMap)
+	-- Refs are represented as IDs in the same space that Rojo's protocol uses.
+	if virtualValue.Type == "Ref" then
+		if virtualValue.Value == nil then
+			return true, nil
+		end
+
+		local instance = instanceMap.fromIds[virtualValue.Value]
+
+		if instance ~= nil then
+			return true, instance
+		else
+			return false, Error.new(Error.RefDidNotExist, {
+				virtualValue = virtualValue,
+			})
+		end
+	end
+
+	local ok, decodedValue = RbxDom.EncodedValue.decode(virtualValue)
+
+	if not ok then
+		return false, Error.new(Error.CannotDecodeValue, {
+			virtualValue = virtualValue,
+			innerError = decodedValue,
+		})
+	end
+
+	return true, decodedValue
+end
+
+return decodeValue

plugin/src/Reconciler/diff.lua

@@ -0,0 +1,148 @@
+--[[
+	Defines the process for diffing a virtual DOM and the real DOM to compute a
+	patch that can be later applied.
+]]
+
+local Log = require(script.Parent.Parent.Parent.Log)
+local invariant = require(script.Parent.Parent.invariant)
+local getProperty = require(script.Parent.getProperty)
+local Error = require(script.Parent.Error)
+local decodeValue = require(script.Parent.decodeValue)
+
+local function isEmpty(table)
+	return next(table) == nil
+end
+
+local function shouldDeleteUnknownInstances(virtualInstance)
+	if virtualInstance.Metadata ~= nil then
+		return not virtualInstance.Metadata.ignoreUnknownInstances
+	else
+		return true
+	end
+end
+
+local function diff(instanceMap, virtualInstances, rootId)
+	local patch = {
+		removed = {},
+		added = {},
+		updated = {},
+	}
+
+	-- Add a virtual instance and all of its descendants to the patch, marked as
+	-- being added.
+	local function markIdAdded(id)
+		local virtualInstance = virtualInstances[id]
+		patch.added[id] = virtualInstance
+
+		for _, childId in ipairs(virtualInstance.Children) do
+			markIdAdded(childId)
+		end
+	end
+
+	-- Internal recursive kernel for diffing an instance with the given ID.
+	local function diffInternal(id)
+		local virtualInstance = virtualInstances[id]
+		local instance = instanceMap.fromIds[id]
+
+		if virtualInstance == nil then
+			invariant("Cannot diff an instance not present in virtualInstances\nID: {}", id)
+		end
+
+		if instance == nil then
+			invariant("Cannot diff an instance not present in InstanceMap\nID: {}", id)
+		end
+
+		if virtualInstance.ClassName ~= instance.ClassName then
+			error("unimplemented: support changing ClassName")
+		end
+
+		local changedName = nil
+		if virtualInstance.Name ~= instance.Name then
+			changedName = virtualInstance.Name
+		end
+
+		local changedProperties = {}
+		for propertyName, virtualValue in pairs(virtualInstance.Properties) do
+			local ok, existingValueOrErr = getProperty(instance, propertyName)
+
+			if ok then
+				local existingValue = existingValueOrErr
+				local ok, decodedValue = decodeValue(virtualValue, instanceMap)
+
+				if ok then
+					if existingValue ~= decodedValue then
+						changedProperties[propertyName] = virtualValue
+					end
+				else
+					Log.warn("Failed to decode property of type {}", virtualValue.Type)
+				end
+			else
+				local err = existingValueOrErr
+
+				if err.kind == Error.UnknownProperty then
+					Log.trace("Skipping unknown property {}.{}", err.details.className, err.details.propertyName)
+				elseif err.kind == Error.UnreadableProperty then
+					Log.trace("Skipping unreadable property {}.{}", err.details.className, err.details.propertyName)
+				else
+					return false, err
+				end
+			end
+		end
+
+		if changedName ~= nil or not isEmpty(changedProperties) then
+			table.insert(patch.updated, {
+				id = id,
+				changedName = changedName,
+				changedClassName = nil,
+				changedProperties = changedProperties,
+				changedMetadata = nil,
+			})
+		end
+
+		-- Traverse the list of children in the DOM. Any instance that has no
+		-- corresponding virtual instance should be removed. Any instance that
+		-- does have a corresponding virtual instance is recursively diffed.
+		for _, childInstance in ipairs(instance:GetChildren()) do
+			local childId = instanceMap.fromInstances[childInstance]
+
+			if childId == nil then
+				-- This is an existing instance not present in the virtual DOM.
+				-- We can mark it for deletion unless the user has asked us not
+				-- to delete unknown stuff.
+				if shouldDeleteUnknownInstances(virtualInstance) then
+					table.insert(patch.removed, childInstance)
+				end
+			else
+				local ok, err = diffInternal(childId)
+
+				if not ok then
+					return false, err
+				end
+			end
+		end
+
+		-- Traverse the list of children in the virtual DOM. Any virtual
+		-- instance that has no corresponding real instance should be created.
+		for _, childId in ipairs(virtualInstance.Children) do
+			local childInstance = instanceMap.fromIds[childId]
+
+			if childInstance == nil then
+				-- This instance is present in the virtual DOM, but doesn't
+				-- exist in the real DOM.
+				markIdAdded(childId)
+			end
+		end
+
+		return true
+	end
+
+	local ok, err = diffInternal(rootId)
+
+	if not ok then
+		return false, err
+	end
+
+	return true, patch
+end
+
+return diff