Build releases on tag push instead of release creation

* Add Glob wrapper type with better serialization

* Introduce PathIgnoreRule struct

* Implement equality for Glob type

* Add PathIgnoreRule to InstanceContext

* Implement glob ignores in directory middleware

* Fix up filters

* Use Iterator::all instead of loop

* Add project-level configuration for glob ignores

* Add test project for glob ignores

* Wire up project file and snapshots to make glob ignores work

* Better codepaths for adding ignore rules with empty iterators

* Add test for globs inherited from parent projects

* Add test details, support glob ignores in nested projects

* Add feature flag for globs

* Switch to use ExactSizeIterator instead of size_hint

* Remove glob visitor

.editorconfig

@@ -3,16 +3,24 @@ root = true
 [*]
 end_of_line = lf
 charset = utf-8
-insert_final_newline = false
 trim_trailing_whitespace = true
+insert_final_newline = false
 
 [*.{json,js,css}]
 indent_style = space
 indent_size = 2
 
-[*.{md,rs}]
+[*.md]
 indent_style = space
 indent_size = 4
 
+[*.{rs,toml}]
+indent_style = space
+indent_size = 4
+insert_final_newline = true
+
+[*.snap]
+insert_final_newline = true
+
 [*.lua]
 indent_style = tab

.github/workflows/ci.yml

@@ -0,0 +1,36 @@
+name: CI
+
+on: [push]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    strategy:
+      matrix:
+        rust_version: [stable, "1.36.0"]
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Setup Rust toolchain
+      run: rustup default ${{ matrix.rust_version }}
+
+    - name: Build
+      run: cargo build --locked --verbose
+
+    - name: Run tests
+      run: cargo test --locked --verbose
+
+    - name: Rustfmt and Clippy
+      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

.github/workflows/release.yml

@@ -0,0 +1,60 @@
+name: Release
+
+on:
+  push:
+    tags: ["*"]
+
+jobs:
+  windows:
+    runs-on: windows-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Build release binary
+      run: cargo build --verbose --locked --release
+
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: rojo-win64
+        path: target/release/rojo.exe
+
+  macos:
+    runs-on: macos-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Install Rust
+      run: curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
+
+    - name: Build release binary
+      run: |
+        source $HOME/.cargo/env
+        cargo build --verbose --locked --release
+      env:
+        OPENSSL_STATIC: 1
+
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: rojo-macos
+        path: target/release/rojo
+
+  linux:
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v1
+
+    - name: Build
+      run: cargo build --locked --verbose --release
+      env:
+        OPENSSL_STATIC: 1
+
+    - name: Upload artifacts
+      uses: actions/upload-artifact@v1
+      with:
+        name: rojo-linux
+        path: target/release/rojo

.gitignore

@@ -1,9 +1,18 @@
+# Rust output directory
 /target
-/scratch-project
-/server/failed-snapshots/
-**/*.rs.bk
+
+# Headers for clibrojo
+/include
+
+# Roblox model and place files in the root, used for debugging
 /*.rbxm
 /*.rbxmx
 /*.rbxl
 /*.rbxlx
+
+# Roblox Studio holds 'lock' files on places
+*.rbxl.lock
+*.rbxlx.lock
+
+# Snapshot files from the 'insta' Rust crate
 **/*.snap.new

.gitmodules

@@ -4,9 +4,6 @@
 [submodule "plugin/modules/testez"]
 	path = plugin/modules/testez
 	url = https://github.com/Roblox/testez.git
-[submodule "plugin/modules/lemur"]
-	path = plugin/modules/lemur
-	url = https://github.com/LPGhatguy/lemur.git
 [submodule "plugin/modules/promise"]
 	path = plugin/modules/promise
 	url = https://github.com/LPGhatguy/roblox-lua-promise.git

.luacheckrc

@@ -20,6 +20,7 @@ stds.roblox = {
 		"CFrame",
 		"Enum",
 		"Instance",
+		"DockWidgetPluginGuiInfo",
 	}
 }
 

.travis.yml

@@ -1,44 +0,0 @@
-matrix:
-  include:
-    # Lua tests are currently disabled because of holes in Lemur that are pretty
-    # tedious to fix. It should be fixed by either adding missing features to
-    # Lemur or by migrating to a CI system based on real Roblox instead.
-
-    # - language: python
-    #   env:
-    #     - LUA="lua=5.1"
-
-    #   before_install:
-    #     - pip install hererocks
-    #     - hererocks lua_install -r^ --$LUA
-    #     - export PATH=$PATH:$PWD/lua_install/bin
-
-    #   install:
-    #     - luarocks install luafilesystem
-    #     - luarocks install busted
-    #     - luarocks install luacov
-    #     - luarocks install luacov-coveralls
-    #     - luarocks install luacheck
-
-    #   script:
-    #     - cd plugin
-    #     - luacheck src
-    #     - lua -lluacov spec.lua
-
-    #   after_success:
-    #     - cd plugin
-    #     - luacov-coveralls -e $TRAVIS_BUILD_DIR/lua_install
-
-    - language: rust
-      rust: 1.34.0
-      cache: cargo
-
-      script:
-        - cargo test --verbose
-
-    - language: rust
-      rust: stable
-      cache: cargo
-
-      script:
-        - cargo test --verbose

CHANGELOG.md

@@ -2,11 +2,29 @@
 
 ## Unreleased Changes
 
-## [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.
+## [0.6.0 Alpha 1](https://github.com/rojo-rbx/rojo/releases/tag/v0.6.0-alpha.1) (January 22, 2020)
 
-## [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))
+### General
+* Added support for nested project files. ([#95](https://github.com/rojo-rbx/rojo/issues/95))
+* Added project file hot-reloading. ([#10](https://github.com/rojo-rbx/rojo/issues/10)])
+* Fixed Rojo dropping Ref properties ([#142](https://github.com/rojo-rbx/rojo/issues/142))
+    * This means that properties like `PrimaryPart` now work!
+* Improved live sync protocol to reduce round-trips and improve syncing consistency.
+* Improved support for binary model files and places.
+
+### Command Line
+* Added `--verbose`/`-v` flag, which can be specified multiple times to increase verbosity.
+* Added support for automatically finding Roblox Studio's auth cookie for `rojo upload` on Windows.
+* Added support for building, serving and uploading sources that aren't Rojo projects.
+* Improved feedback from `rojo serve`.
+* Removed support for legacy `roblox-project.json` projects, deprecated in an early Rojo 0.5.0 alpha.
+* Rojo no longer traverses directories upwards looking for project files.
+    * Though undocumented, Rojo 0.5.x will search for a project file contained in any ancestor folders. This feature was removed to better support other 0.6.x features.
+
+### Roblox Studio Plugin
+* Added "connecting" state to improve experience when live syncing.
+* 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.
 
 ## [0.5.1](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))

CONTRIBUTING.md

@@ -11,6 +11,13 @@ Some of the repositories covered are:
 ## Code
 Code contributions are welcome for features and bugs that have been reported in the project's bug tracker. We want to make sure that no one wastes their time, so be sure to talk with maintainers about what changes would be accepted before doing any work!
 
+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)
+
 ## Documentation
 Documentation impacts way more people than the individual lines of code we write.
 

Cargo.toml

@@ -1,8 +1,97 @@
-[workspace]
-members = [
-	"server",
-	"rojo-test",
+[package]
+name = "rojo"
+version = "0.6.0-alpha.1"
+authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+description = "Enables professional-grade development tools for Roblox developers"
+license = "MPL-2.0"
+homepage = "https://rojo.space"
+documentation = "https://rojo.space/docs"
+repository = "https://github.com/rojo-rbx/rojo"
+readme = "README.md"
+edition = "2018"
+
+exclude = [
+    "/plugin/**",
+    "/test-projects/**",
 ]
 
-[profile.dev]
-opt-level = 1
+[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",
+]
+
+default-members = [
+    ".",
+    "rojo-test",
+    "rojo-insta-ext",
+]
+
+[lib]
+name = "librojo"
+path = "src/lib.rs"
+
+[[bin]]
+name = "rojo"
+path = "src/bin.rs"
+
+[[bench]]
+name = "build"
+harness = false
+
+[dependencies]
+crossbeam-channel = "0.4.0"
+csv = "1.1.1"
+env_logger = "0.7.1"
+futures = "0.1.29"
+globset = "0.4.4"
+humantime = "1.3.0"
+hyper = "0.12.35"
+jod-thread = "0.1.0"
+lazy_static = "1.4.0"
+log = "0.4.8"
+maplit = "1.0.1"
+notify = "4.0.14"
+rbx_binary = "0.5.0"
+rbx_dom_weak = "1.10.1"
+rbx_reflection = "3.3.408"
+rbx_xml = "0.11.3"
+regex = "1.3.1"
+reqwest = "0.9.20"
+ritz = "0.1.0"
+rlua = "0.17.0"
+serde = { version = "1.0", features = ["derive", "rc"] }
+serde_json = "1.0"
+snafu = "0.6.0"
+structopt = "0.3.5"
+termcolor = "1.0.5"
+uuid = { version = "0.8.1", features = ["v4", "serde"] }
+
+[target.'cfg(windows)'.dependencies]
+winreg = "0.6.2"
+
+[dev-dependencies]
+rojo-insta-ext = { path = "rojo-insta-ext" }
+
+criterion = "0.3"
+insta = { version = "0.12.0", 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

@@ -7,14 +7,11 @@
 <div>&nbsp;</div>
 
 <div align="center">
-    <a href="https://travis-ci.org/rojo-rbx/rojo">
-        <img src="https://api.travis-ci.org/rojo-rbx/rojo.svg?branch=master" alt="Travis-CI Build Status" />
+    <a href="https://github.com/rojo-rbx/rojo/actions">
+        <img src="https://github.com/rojo-rbx/rojo/workflows/CI/badge.svg" alt="Actions status" />
     </a>
     <a href="https://crates.io/crates/rojo">
-        <img src="https://img.shields.io/crates/v/rojo.svg?label=version" alt="Latest server version" />
-    </a>
-    <a href="https://rojo.space/docs/0.4.x">
-        <img src="https://img.shields.io/badge/docs-0.4.x-brightgreen.svg" alt="Rojo 0.4.x Documentation" />
+        <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" />
@@ -44,7 +41,7 @@ Soon, Rojo will be able to:
 * Automatically manage your assets on Roblox.com, like images and sounds
 * Import custom instances like MoonScript code
 
-## [Documentation](https://rojo.space/docs/latest)
+## [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!
 
 ## Contributing
@@ -52,7 +49,7 @@ Check out our [contribution guide](CONTRIBUTING.md) for detailed instructions fo
 
 Pull requests are welcome!
 
-Rojo supports Rust 1.34.0 and newer. The minimum supported version of Rust is based on the latest versions of the dependencies that Rojo has.
+Rojo supports Rust 1.36.0 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/index.css

@@ -0,0 +1,181 @@
+* {
+  margin: 0;
+  padding: 0;
+  border: none;
+  text-decoration: inherit;
+  color: inherit;
+  font: inherit;
+  box-sizing: inherit;
+  line-height: inherit;
+}
+
+html {
+  box-sizing: border-box;
+  font-family: sans-serif;
+  font-size: 18px;
+  text-decoration: none;
+  line-height: 1.4;
+}
+
+img {
+  max-width:100%;
+  max-height:100%;
+  height: auto;
+}
+
+.path-list > li {
+  margin-left: 1.2em;
+  font-family: monospace;
+}
+
+.root {
+  display: flex;
+  flex-direction: column;
+  margin: 0.5rem auto;
+  width: 100%;
+  max-width: 50rem;
+  background-color: #efefef;
+  border: 1px solid #666;
+  border-radius: 4px;
+}
+
+.header {
+  flex: 0 0;
+  display: flex;
+  flex-wrap: wrap;
+  align-items: center;
+  border-bottom: 1px solid #666;
+}
+
+.main {
+  padding: 1rem;
+}
+
+.main-logo {
+  flex: 0 0 10rem;
+  margin: 1rem;
+}
+
+.stats {
+  flex: 0 0 20rem;
+  margin: 1rem;
+}
+
+.stat {
+  display: block;
+}
+
+.stat-name {
+  display: inline;
+  font-weight: bold;
+}
+
+.main-section:not(:last-of-type) {
+  margin-bottom: 1rem;
+}
+
+.section-title {
+  font-size: 1.8rem;
+}
+
+.button-list {
+  flex: 0 0;
+  display: flex;
+  flex-wrap: wrap;
+  justify-content: space-around;
+  margin: -1rem;
+}
+
+.button {
+  display: inline-block;
+  border: 1px solid #666;
+  padding: 0.3em 1em;
+  margin: 1rem;
+}
+
+.instance {
+  margin-bottom: 0.5rem;
+}
+
+.instance-title {
+  font-size: 1.2rem;
+  padding: 0.5rem;
+}
+
+.expandable-section {
+  margin: 0.25rem 0.5rem;
+}
+
+.expandable-items {
+  padding: 0.5rem 1rem;
+}
+
+.expandable-input {
+  display: none;
+}
+
+.expandable-label > label {
+  cursor: pointer;
+  display: flex;
+  align-items: center;
+  align-content: center;
+}
+
+.expandable-input ~ .expandable-label .expandable-visualizer {
+  font-family: monospace;
+  display: inline-flex;
+  align-items: center;
+  align-content: center;
+  text-align: center;
+  width: 1rem;
+  height: 1rem;
+  font-size: 2rem;
+  margin: 0 0.5rem;
+  transition: transform 100ms ease-in-out;
+  transform-origin: 60% 60%;
+}
+
+.expandable-visualizer::before {
+  content: "›";
+  font-weight: bold;
+}
+
+.expandable-input:checked ~ .expandable-label {
+  border-bottom: 1px solid #bbb;
+}
+
+.expandable-input:checked ~ .expandable-label .expandable-visualizer {
+  transform: rotate(90deg);
+}
+
+.expandable-input:not(:checked) ~ .expandable-items {
+  display: none;
+}
+
+.vfs-entry {
+}
+
+.vfs-entry-name {
+  position: relative;
+  font-family: monospace;
+}
+
+.vfs-entry-children .vfs-entry-name::before {
+  content: "";
+  width: 0.6em;
+  height: 1px;
+  background-color: #999;
+  position: absolute;
+  top: 50%;
+  left: -0.8em;
+}
+
+.vfs-entry-note {
+  font-style: italic;
+}
+
+.vfs-entry-children {
+  padding-left: 0.8em;
+  margin-left: 0.2em;
+  border-left: 1px solid #999;
+}

assets/kenney-ui-gray-sheet.xml

@@ -1,41 +0,0 @@
-<TextureAtlas imagePath="sheet.png">
-	<SubTexture name="grey_arrowDownGrey.png" x="78" y="498" width="15" height="10"/>
-	<SubTexture name="grey_arrowDownWhite.png" x="123" y="496" width="15" height="10"/>
-	<SubTexture name="grey_arrowUpGrey.png" x="108" y="498" width="15" height="10"/>
-	<SubTexture name="grey_arrowUpWhite.png" x="93" y="498" width="15" height="10"/>
-	<SubTexture name="grey_box.png" x="147" y="433" width="38" height="36"/>
-	<SubTexture name="grey_boxCheckmark.png" x="147" y="469" width="38" height="36"/>
-	<SubTexture name="grey_boxCross.png" x="185" y="433" width="38" height="36"/>
-	<SubTexture name="grey_boxTick.png" x="190" y="198" width="36" height="36"/>
-	<SubTexture name="grey_button00.png" x="0" y="143" width="190" height="45"/>
-	<SubTexture name="grey_button01.png" x="0" y="188" width="190" height="49"/>
-	<SubTexture name="grey_button02.png" x="0" y="98" width="190" height="45"/>
-	<SubTexture name="grey_button03.png" x="0" y="331" width="190" height="49"/>
-	<SubTexture name="grey_button04.png" x="0" y="286" width="190" height="45"/>
-	<SubTexture name="grey_button05.png" x="0" y="0" width="195" height="49"/>
-	<SubTexture name="grey_button06.png" x="0" y="49" width="191" height="49"/>
-	<SubTexture name="grey_button07.png" x="195" y="0" width="49" height="49"/>
-	<SubTexture name="grey_button08.png" x="240" y="49" width="49" height="49"/>
-	<SubTexture name="grey_button09.png" x="98" y="433" width="49" height="45"/>
-	<SubTexture name="grey_button10.png" x="191" y="49" width="49" height="49"/>
-	<SubTexture name="grey_button11.png" x="0" y="433" width="49" height="45"/>
-	<SubTexture name="grey_button12.png" x="244" y="0" width="49" height="49"/>
-	<SubTexture name="grey_button13.png" x="49" y="433" width="49" height="45"/>
-	<SubTexture name="grey_button14.png" x="0" y="384" width="190" height="49"/>
-	<SubTexture name="grey_button15.png" x="0" y="237" width="190" height="49"/>
-	<SubTexture name="grey_checkmarkGrey.png" x="99" y="478" width="21" height="20"/>
-	<SubTexture name="grey_checkmarkWhite.png" x="78" y="478" width="21" height="20"/>
-	<SubTexture name="grey_circle.png" x="185" y="469" width="36" height="36"/>
-	<SubTexture name="grey_crossGrey.png" x="120" y="478" width="18" height="18"/>
-	<SubTexture name="grey_crossWhite.png" x="190" y="318" width="18" height="18"/>
-	<SubTexture name="grey_panel.png" x="190" y="98" width="100" height="100"/>
-	<SubTexture name="grey_sliderDown.png" x="190" y="234" width="28" height="42"/>
-	<SubTexture name="grey_sliderEnd.png" x="138" y="478" width="8" height="10"/>
-	<SubTexture name="grey_sliderHorizontal.png" x="0" y="380" width="190" height="4"/>
-	<SubTexture name="grey_sliderLeft.png" x="0" y="478" width="39" height="31"/>
-	<SubTexture name="grey_sliderRight.png" x="39" y="478" width="39" height="31"/>
-	<SubTexture name="grey_sliderUp.png" x="190" y="276" width="28" height="42"/>
-	<SubTexture name="grey_sliderVertical.png" x="208" y="318" width="4" height="100"/>
-	<SubTexture name="grey_tickGrey.png" x="190" y="336" width="17" height="17"/>
-	<SubTexture name="grey_tickWhite.png" x="190" y="353" width="17" height="17"/>
-</TextureAtlas>

benches/build.rs

@@ -0,0 +1,42 @@
+use std::path::Path;
+
+use criterion::{criterion_group, criterion_main, BatchSize, Criterion};
+use tempfile::{tempdir, TempDir};
+
+use librojo::cli::{build, BuildCommand};
+
+pub fn benchmark_small_place(c: &mut Criterion) {
+    bench_build_place(c, "Small Place", "test-projects/benchmark_small_place")
+}
+
+criterion_group!(benches, benchmark_small_place);
+criterion_main!(benches);
+
+fn bench_build_place(c: &mut Criterion, name: &str, path: &str) {
+    let mut group = c.benchmark_group(name);
+
+    // 'rojo build' generally takes a fair bit of time to execute.
+    group.sample_size(10);
+    group.bench_function("build", |b| {
+        b.iter_batched(
+            || place_setup(path),
+            |(_dir, options)| build(options).unwrap(),
+            BatchSize::SmallInput,
+        )
+    });
+
+    group.finish();
+}
+
+fn place_setup<P: AsRef<Path>>(input_path: P) -> (TempDir, BuildCommand) {
+    let dir = tempdir().unwrap();
+    let input = input_path.as_ref().to_path_buf();
+    let output = dir.path().join("output.rbxlx");
+
+    let options = BuildCommand {
+        project: input,
+        output,
+    };
+
+    (dir, options)
+}

bin/dev-plugin.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+set -e
+
+watchexec -c -w plugin "sh -c './bin/install-dev-plugin.sh'"

bin/install-dev-plugin.sh

@@ -0,0 +1,13 @@
+#!/bin/sh
+
+set -e
+
+DIR="$( mktemp -d )"
+PLUGIN_FILE="$DIR/Rojo.rbxm"
+TESTEZ_FILE="$DIR/TestEZ.rbxm"
+
+rojo build plugin -o "$PLUGIN_FILE"
+rojo build plugin/testez.project.json -o "$TESTEZ_FILE"
+remodel bin/mark-plugin-as-dev.lua "$PLUGIN_FILE" "$TESTEZ_FILE" 2>/dev/null
+
+cp "$PLUGIN_FILE" "$LOCALAPPDATA/Roblox/Plugins/Rojo.rbxm"

bin/install-release-plugin.sh

@@ -0,0 +1,5 @@
+#!/bin/sh
+
+set -e
+
+rojo build plugin -o "$LOCALAPPDATA/Roblox/Plugins/Rojo.rbxm"

bin/mark-plugin-as-dev.lua

@@ -0,0 +1,12 @@
+local pluginPath, testezPath = ...
+
+local plugin = remodel.readModelFile(pluginPath)[1]
+local testez = remodel.readModelFile(testezPath)[1]
+
+local marker = Instance.new("Folder")
+marker.Name = "ROJO_DEV_BUILD"
+marker.Parent = plugin
+
+testez.Parent = plugin
+
+remodel.writeModelFile(plugin, pluginPath)

bin/put-plugin-in-test-place.lua

@@ -0,0 +1,8 @@
+local pluginPath, placePath = ...
+
+local plugin = remodel.readModelFile(pluginPath)[1]
+local place = remodel.readPlaceFile(placePath)
+
+plugin.Parent = place:GetService("ReplicatedStorage")
+
+remodel.writePlaceFile(place, placePath)

bin/run-all-tests.sh

@@ -0,0 +1,6 @@
+#!/bin/sh
+
+set -e
+
+./bin/run-cli-tests.sh
+./bin/run-plugin-tests.sh

bin/run-cli-tests.sh

@@ -0,0 +1,9 @@
+#!/bin/sh
+
+set -e
+
+cargo test --all --locked
+cargo fmt -- --check
+
+touch src/lib.rs # Nudge Rust source to make Clippy actually check things
+cargo clippy

bin/run-plugin-tests.sh

@@ -0,0 +1,16 @@
+#!/bin/sh
+
+set -e
+
+DIR="$( mktemp -d )"
+PLUGIN_FILE="$DIR/Rojo.rbxmx"
+PLACE_FILE="$DIR/RojoTestPlace.rbxlx"
+
+rojo build plugin -o "$PLUGIN_FILE"
+rojo build plugin/place.project.json -o "$PLACE_FILE"
+
+remodel bin/put-plugin-in-test-place.lua "$PLUGIN_FILE" "$PLACE_FILE"
+
+run-in-roblox -s plugin/testBootstrap.server.lua "$PLACE_FILE"
+
+luacheck plugin/src plugin/log plugin/http

bin/test-scratch-project

@@ -1,21 +0,0 @@
-#!/bin/sh
-
-# Copies a project from 'test-projects' into a folder that can be messed with
-# without accidentally checking the results into version control.
-
-set -e
-
-if [ ! -d "test-projects/$1" ]
-then
-	echo "Pick a project that exists!"
-	exit 1
-fi
-
-if [ -d "scratch-project/$1" ]
-then
-	rm -rf "scratch-project/$1"
-fi
-
-mkdir -p scratch-project
-cp -r "test-projects/$1" scratch-project
-cargo run -- serve "scratch-project/$1"

clibrojo/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "clibrojo"
+version = "0.1.0"
+authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+edition = "2018"
+
+[lib]
+crate-type = ["cdylib"]
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+rojo = { path = ".." }

clibrojo/README.md

@@ -0,0 +1,19 @@
+# Rojo as a C Library
+This is an experiment to expose a C API for Rojo that would be suitable for embedding it into an existing C/C++ application.
+
+I'm hoping to expand it to drop the HTTP layer and communicate through a channel, which could make it feasible to embed into an existing Roblox IDE with minimal changes or additional code.
+
+## Building
+This project is currently not built by default and could break/disappear at any time.
+
+```bash
+cargo build -p clibrojo
+```
+
+On Windows, Cargo will generate a `clibrojo.dll` and associated `.lib` file. Link these into your project.
+
+To generate the associated C header file to include in the project, use [cbindgen](https://github.com/eqrion/cbindgen):
+
+```bash
+cbindgen --crate clibrojo --output include/rojo.h
+```

clibrojo/src/lib.rs

@@ -0,0 +1,14 @@
+use std::{ffi::CStr, os::raw::c_char, path::PathBuf};
+
+use librojo::commands::{serve, ServeOptions};
+
+#[no_mangle]
+pub extern "C" fn rojo_serve(path: *const c_char) {
+    let path = unsafe { PathBuf::from(CStr::from_ptr(path).to_str().unwrap()) };
+
+    serve(&ServeOptions {
+        fuzzy_project_path: path,
+        port: None,
+    })
+    .unwrap();
+}

design.gv

@@ -0,0 +1,30 @@
+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/guide/new-game.md

@@ -87,4 +87,4 @@ Generating and publishing your game is as simple as:
 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)
+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/index.md

@@ -1,4 +1,11 @@
-This is the documentation home for **Rojo 0.5.x**.
+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:
 

docs/why-rojo.md

@@ -12,7 +12,7 @@ Rojo opens the door to use the absolute best text editors in the world and their
 
 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, goto symbol, multi-file regex find and replace, bookmarks and much more.
+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:
 
@@ -41,4 +41,4 @@ 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
+* [Tokei](https://github.com/XAMPPRocky/tokei), a tool for statistics like lines of code

plugin/.gitignore

@@ -1 +0,0 @@
-/luacov.*

plugin/.luacov

@@ -1,8 +0,0 @@
-return {
-	include = {
-		"^src",
-	},
-	exclude = {
-		"%.spec$",
-	},
-}

plugin/default.project.json

@@ -5,6 +5,15 @@
     "Plugin": {
       "$path": "src"
     },
+    "Log": {
+      "$path": "log"
+    },
+    "Http": {
+      "$path": "http"
+    },
+    "Fmt": {
+      "$path": "fmt"
+    },
     "Roact": {
       "$path": "modules/roact/src"
     },

plugin/fmt/init.lua

@@ -0,0 +1,245 @@
+--[[
+	This library describes a formatting mechanism akin to Rust's std::fmt.
+
+	It has a couple building blocks:
+
+	* A new syntax for formatting strings, taken verbatim from Rust. It'd also
+	  be possible to use printf-style formatting specifiers to integrate with
+	  the existing string.format utility.
+
+	* An equivalent to Rust's `Display` trait. We're mapping the semantics of
+	  tostring and the __tostring metamethod onto this trait. A lot of types
+	  should already have __tostring implementations, too!
+
+	* An equivalent to Rust's `Debug` trait. This library Lua-ifies that idea by
+	  inventing a new metamethod, `__fmtDebug`. We pass along the "extended
+	  form" attribute which is the equivalent of the "alternate mode" in Rust's
+	  Debug trait since it's the author's opinion that treating it as a
+	  verbosity flag is semantically accurate.
+]]
+
+--[[
+	The default implementation of __fmtDebug for tables when the extended option
+	is not set.
+]]
+local function defaultTableDebug(buffer, input)
+	buffer:writeRaw("{")
+
+	for key, value in pairs(input) do
+		buffer:write("[{:?}] = {:?}", key, value)
+
+		if next(input, key) ~= nil then
+			buffer:writeRaw(", ")
+		end
+	end
+
+	buffer:writeRaw("}")
+end
+
+--[[
+	The default implementation of __fmtDebug for tables with the extended option
+	set.
+]]
+local function defaultTableDebugExtended(buffer, input)
+	-- Special case for empty tables.
+	if next(input) == nil then
+		buffer:writeRaw("{}")
+		return
+	end
+
+	buffer:writeLineRaw("{")
+	buffer:indent()
+
+	for key, value in pairs(input) do
+		buffer:writeLine("[{:?}] = {:#?},", key, value)
+	end
+
+	buffer:unindent()
+	buffer:writeRaw("}")
+end
+
+--[[
+	The default debug representation for all types.
+]]
+local function debugImpl(buffer, value, extendedForm)
+	local valueType = typeof(value)
+
+	if valueType == "string" then
+		local formatted = string.format("%q", value)
+		buffer:writeRaw(formatted)
+	elseif valueType == "table" then
+		local valueMeta = getmetatable(value)
+
+		if valueMeta ~= nil and  valueMeta.__fmtDebug ~= nil then
+			-- This type implement's the metamethod we made up to line up with
+			-- Rust's 'Debug' trait.
+
+			valueMeta.__fmtDebug(value, buffer, extendedForm)
+		else
+			if extendedForm then
+				defaultTableDebugExtended(buffer, value)
+			else
+				defaultTableDebug(buffer, value)
+			end
+		end
+	elseif valueType == "Instance" then
+		buffer:writeRaw(value:GetFullName())
+	else
+		buffer:writeRaw(tostring(value))
+	end
+end
+
+--[[
+	Defines and implements the library's template syntax.
+]]
+local function writeFmt(buffer, template, ...)
+	local currentArg = 0
+	local i = 1
+	local len = #template
+
+	while i <= len do
+		local openBrace = template:find("{", i)
+
+		if openBrace == nil then
+			-- There are no remaining open braces in this string, so we can
+			-- write the rest of the string to the buffer.
+
+			buffer:writeRaw(template:sub(i))
+			break
+		else
+			-- We found an open brace! This could be:
+			-- - A literal '{', written as '{{'
+			-- - The beginning of an interpolation, like '{}'
+			-- - An error, if there's no matching '}'
+
+			local charAfterBrace = template:sub(openBrace + 1, openBrace + 1)
+			if charAfterBrace == "{" then
+				-- This is a literal brace, so we'll write everything up to this
+				-- point (including the first brace), and then skip over the
+				-- second brace.
+
+				buffer:writeRaw(template:sub(i, openBrace))
+				i = openBrace + 2
+			else
+				-- This SHOULD be an interpolation. We'll find our matching
+				-- brace and treat the contents as the formatting specifier.
+
+				-- If there were any unwritten characters before this
+				-- interpolation, write them to the buffer.
+				if openBrace - i > 0 then
+					buffer:writeRaw(template:sub(i, openBrace - 1))
+				end
+
+				local closeBrace = template:find("}", openBrace + 1)
+				assert(closeBrace ~= nil, "Unclosed formatting specifier. Use '{{' to write an open brace.")
+
+				local formatSpecifier = template:sub(openBrace + 1, closeBrace - 1)
+				currentArg = currentArg + 1
+				local arg = select(currentArg, ...)
+
+				if formatSpecifier == "" then
+					-- This should use the equivalent of Rust's 'Display', ie
+					-- tostring and the __tostring metamethod.
+
+					buffer:writeRaw(tostring(arg))
+				elseif formatSpecifier == ":?" then
+					-- This should use the equivalent of Rust's 'Debug',
+					-- invented for this library as __fmtDebug.
+
+					debugImpl(buffer, arg, false)
+				elseif formatSpecifier == ":#?" then
+					-- This should use the equivlant of Rust's 'Debug' with the
+					-- 'alternate' (ie expanded) flag set.
+
+					debugImpl(buffer, arg, true)
+				else
+					error("unsupported format specifier " .. formatSpecifier, 2)
+				end
+
+				i = closeBrace + 1
+			end
+		end
+	end
+end
+
+local function debugOutputBuffer()
+	local buffer = {}
+	local startOfLine = true
+	local indentLevel = 0
+	local indentation = ""
+
+	function buffer:writeLine(template, ...)
+		writeFmt(self, template, ...)
+		self:nextLine()
+	end
+
+	function buffer:writeLineRaw(value)
+		self:writeRaw(value)
+		self:nextLine()
+	end
+
+	function buffer:write(template, ...)
+		return writeFmt(self, template, ...)
+	end
+
+	function buffer:writeRaw(value)
+		if #value > 0 then
+			if startOfLine and #indentation > 0 then
+				startOfLine = false
+				table.insert(self, indentation)
+			end
+
+			table.insert(self, value)
+			startOfLine = false
+		end
+	end
+
+	function buffer:nextLine()
+		table.insert(self, "\n")
+		startOfLine = true
+	end
+
+	function buffer:indent()
+		indentLevel = indentLevel + 1
+		indentation = string.rep("    ", indentLevel)
+	end
+
+	function buffer:unindent()
+		indentLevel = math.max(0, indentLevel - 1)
+		indentation = string.rep("    ", indentLevel)
+	end
+
+	function buffer:finish()
+		return table.concat(self, "")
+	end
+
+	return buffer
+end
+
+local function fmt(template, ...)
+	local buffer = debugOutputBuffer()
+	writeFmt(buffer, template, ...)
+	return buffer:finish()
+end
+
+--[[
+	Wrap the given object in a type that implements the given function as its
+	Debug implementation, and forwards __tostring to the type's underlying
+	tostring implementation.
+]]
+local function debugify(object, fmtFunc)
+	return setmetatable({}, {
+		__fmtDebug = function(_, ...)
+			return fmtFunc(object, ...)
+		end,
+		__tostring = function()
+			return tostring(object)
+		end,
+	})
+end
+
+return {
+	debugOutputBuffer = debugOutputBuffer,
+	fmt = fmt,
+	debugify = debugify,
+}

plugin/http/Error.lua

@@ -1,9 +1,7 @@
-local Logging = require(script.Parent.Logging)
+local Error = {}
+Error.__index = Error
 
-local HttpError = {}
-HttpError.__index = HttpError
-
-HttpError.Error = {
+Error.Kind = {
 	HttpNotEnabled = {
 		message = "Rojo requires HTTP access, which is not enabled.\n" ..
 			"Check your game settings, located in the 'Home' tab of Studio.",
@@ -13,20 +11,20 @@ HttpError.Error = {
 			"Make sure the server is running -- use 'rojo serve' to run it!",
 	},
 	Timeout = {
-		message = "Request timed out.",
+		message = "HTTP request timed out.",
 	},
 	Unknown = {
-		message = "Unknown error: {{message}}",
+		message = "Unknown HTTP error: {{message}}",
 	},
 }
 
-setmetatable(HttpError.Error, {
+setmetatable(Error.Kind, {
 	__index = function(_, key)
-		error(("%q is not a valid member of HttpError.Error"):format(tostring(key)), 2)
+		error(("%q is not a valid member of Http.Error.Kind"):format(tostring(key)), 2)
 	end,
 })
 
-function HttpError.new(type, extraMessage)
+function Error.new(type, extraMessage)
 	extraMessage = extraMessage or ""
 	local message = type.message:gsub("{{message}}", extraMessage)
 
@@ -35,38 +33,34 @@ function HttpError.new(type, extraMessage)
 		message = message,
 	}
 
-	setmetatable(err, HttpError)
+	setmetatable(err, Error)
 
 	return err
 end
 
-function HttpError:__tostring()
+function Error:__tostring()
 	return self.message
 end
 
 --[[
 	This method shouldn't have to exist. Ugh.
 ]]
-function HttpError.fromErrorString(message)
+function Error.fromRobloxErrorString(message)
 	local lower = message:lower()
 
 	if lower:find("^http requests are not enabled") then
-		return HttpError.new(HttpError.Error.HttpNotEnabled)
+		return Error.new(Error.Kind.HttpNotEnabled)
 	end
 
 	if lower:find("^httperror: timedout") then
-		return HttpError.new(HttpError.Error.Timeout)
+		return Error.new(Error.Kind.Timeout)
 	end
 
 	if lower:find("^httperror: connectfail") then
-		return HttpError.new(HttpError.Error.ConnectFailed)
+		return Error.new(Error.Kind.ConnectFailed)
 	end
 
-	return HttpError.new(HttpError.Error.Unknown, message)
+	return Error.new(Error.Kind.Unknown, message)
 end
 
-function HttpError:report()
-	Logging.warn(self.message)
-end
-
-return HttpError
+return Error

plugin/http/Response.lua

@@ -1,34 +1,34 @@
 local HttpService = game:GetService("HttpService")
 
 local stringTemplate = [[
-HttpResponse {
+Http.Response {
 	code: %d
 	body: %s
 }]]
 
-local HttpResponse = {}
-HttpResponse.__index = HttpResponse
+local Response = {}
+Response.__index = Response
 
-function HttpResponse:__tostring()
+function Response:__tostring()
 	return stringTemplate:format(self.code, self.body)
 end
 
-function HttpResponse.fromRobloxResponse(response)
+function Response.fromRobloxResponse(response)
 	local self = {
 		body = response.Body,
 		code = response.StatusCode,
 		headers = response.Headers,
 	}
 
-	return setmetatable(self, HttpResponse)
+	return setmetatable(self, Response)
 end
 
-function HttpResponse:isSuccess()
+function Response:isSuccess()
 	return self.code >= 200 and self.code < 300
 end
 
-function HttpResponse:json()
+function Response:json()
 	return HttpService:JSONDecode(self.body)
 end
 
-return HttpResponse
+return Response

plugin/http/init.lua

@@ -0,0 +1,66 @@
+local HttpService = game:GetService("HttpService")
+
+local Promise = require(script.Parent.Promise)
+local Log = require(script.Parent.Log)
+
+local HttpError = require(script.Error)
+local HttpResponse = require(script.Response)
+
+local lastRequestId = 0
+
+local Http = {}
+
+Http.Error = HttpError
+Http.Response = HttpResponse
+
+local function performRequest(requestParams)
+	local requestId = lastRequestId + 1
+	lastRequestId = requestId
+
+	Log.trace("HTTP {}({}) {}", requestParams.Method, requestId, requestParams.Url)
+
+	if requestParams.Body ~= nil then
+		Log.trace("{}", requestParams.Body)
+	end
+
+	return Promise.new(function(resolve, reject)
+		coroutine.wrap(function()
+			local success, response = pcall(function()
+				return HttpService:RequestAsync(requestParams)
+			end)
+
+			if success then
+				Log.trace("Request {} success, status code {}", requestId, response.StatusCode)
+				resolve(HttpResponse.fromRobloxResponse(response))
+			else
+				Log.trace("Request {} failure: {:?}", requestId, response)
+				reject(HttpError.fromRobloxErrorString(response))
+			end
+		end)()
+	end)
+end
+
+function Http.get(url)
+	return performRequest({
+		Url = url,
+		Method = "GET",
+	})
+end
+
+function Http.post(url, body)
+	return performRequest({
+		Url = url,
+		Method = "POST",
+		Body = body,
+	})
+end
+
+function Http.jsonEncode(object)
+	return HttpService:JSONEncode(object)
+end
+
+function Http.jsonDecode(source)
+	return HttpService:JSONDecode(source)
+end
+
+return Http

plugin/http/init.spec.lua

@@ -0,0 +1,5 @@
+return function()
+	it("should load", function()
+		require(script.Parent)
+	end)
+end

plugin/loadEnvironment.lua

@@ -1,37 +0,0 @@
---[[
-	Loads the Rojo plugin and all of its dependencies.
-]]
-
-local function loadEnvironment()
-	-- If you add any dependencies, add them to this table so they'll be loaded!
-	local LOAD_MODULES = {
-		{"src", "Rojo"},
-		{"modules/promise/lib", "Promise"},
-		{"modules/testez/lib", "TestEZ"},
-	}
-
-	-- This makes sure we can load Lemur and other libraries that depend on init.lua
-	package.path = package.path .. ";?/init.lua"
-
-	-- If this fails, make sure you've run `lua bin/install-dependencies.lua` first!
-	local lemur = require("modules.lemur")
-
-	-- Create a virtual Roblox tree
-	local habitat = lemur.Habitat.new()
-
-	-- We'll put all of our library code and dependencies here
-	local modules = lemur.Instance.new("Folder")
-	modules.Name = "Modules"
-	modules.Parent = habitat.game:GetService("ReplicatedStorage")
-
-	-- Load all of the modules specified above
-	for _, module in ipairs(LOAD_MODULES) do
-		local container = habitat:loadFromFs(module[1])
-		container.Name = module[2]
-		container.Parent = modules
-	end
-
-	return habitat, modules
-end
-
-return loadEnvironment

plugin/log/init.lua

@@ -1,49 +1,55 @@
-local DevSettings = require(script.Parent.DevSettings)
+local Fmt = require(script.Parent.Fmt)
 
 local Level = {
 	Error = 0,
 	Warning = 1,
 	Info = 2,
-	Trace = 3,
+	Debug = 3,
+	Trace = 4,
 }
 
-local testLogLevel = nil
-
 local function getLogLevel()
-	if testLogLevel ~= nil then
-		return testLogLevel
-	end
-
-	return DevSettings:getLogLevel()
+	return Level.Info
 end
 
 local function addTags(tag, message)
 	return tag .. message:gsub("\n", "\n" .. tag)
 end
 
-local INFO_TAG = (" "):rep(15) .. "[Rojo-Info] "
 local TRACE_TAG = (" "):rep(15) .. "[Rojo-Trace] "
+local INFO_TAG = (" "):rep(15) .. "[Rojo-Info] "
+local DEBUG_TAG = (" "):rep(15) .. "[Rojo-Debug] "
 local WARN_TAG = "[Rojo-Warn] "
 
 local Log = {}
 
 Log.Level = Level
 
+function Log.setLogLevelThunk(thunk)
+	getLogLevel = thunk
+end
+
 function Log.trace(template, ...)
 	if getLogLevel() >= Level.Trace then
-		print(addTags(TRACE_TAG, string.format(template, ...)))
+		print(addTags(TRACE_TAG, Fmt.fmt(template, ...)))
 	end
 end
 
 function Log.info(template, ...)
 	if getLogLevel() >= Level.Info then
-		print(addTags(INFO_TAG, string.format(template, ...)))
+		print(addTags(INFO_TAG, Fmt.fmt(template, ...)))
+	end
+end
+
+function Log.debug(template, ...)
+	if getLogLevel() >= Level.Debug then
+		print(addTags(DEBUG_TAG, Fmt.fmt(template, ...)))
 	end
 end
 
 function Log.warn(template, ...)
 	if getLogLevel() >= Level.Warning then
-		warn(addTags(WARN_TAG, string.format(template, ...)))
+		warn(addTags(WARN_TAG, Fmt.fmt(template, ...)))
 	end
 end
 

plugin/log/init.spec.lua

@@ -0,0 +1,5 @@
+return function()
+	it("should load", function()
+		require(script.Parent)
+	end)
+end

plugin/place.project.json

@@ -1,48 +0,0 @@
-{
-  "name": "rojo",
-  "tree": {
-    "$className": "DataModel",
-
-    "ReplicatedStorage": {
-      "$className": "ReplicatedStorage",
-
-      "Rojo": {
-        "$className": "Folder",
-
-        "Plugin": {
-          "$path": "src"
-        },
-        "Roact": {
-          "$path": "modules/roact/src"
-        },
-        "Promise": {
-          "$path": "modules/promise/lib"
-        },
-        "t": {
-          "$path": "modules/t/lib"
-        }
-      },
-      "TestEZ": {
-        "$path": "modules/testez/lib"
-      }
-    },
-
-    "HttpService": {
-      "$className": "HttpService",
-      "$properties": {
-        "HttpEnabled": {
-          "Type": "Bool",
-          "Value": true
-        }
-      }
-    },
-
-    "ServerScriptService": {
-      "$className": "ServerScriptService",
-
-      "TestBootstrap": {
-        "$path": "testBootstrap.server.lua"
-      }
-    }
-  }
-}

plugin/runTest.lua

@@ -1,15 +0,0 @@
-local loadEnvironment = require("loadEnvironment")
-
-local testPath = assert((...), "Please specify a path to a test file.")
-
-local habitat = loadEnvironment()
-
-local testModule = habitat:loadFromFs(testPath)
-
-if testModule == nil then
-	error("Couldn't find test file at " .. testPath)
-end
-
-print("Starting test module.")
-
-habitat:require(testModule)

plugin/spec.lua

@@ -1,17 +0,0 @@
---[[
-	Loads our library and all of its dependencies, then runs tests using TestEZ.
-]]
-
-local loadEnvironment = require("loadEnvironment")
-
-local habitat, modules = loadEnvironment()
-
--- Load TestEZ and run our tests
-local TestEZ = habitat:require(modules.TestEZ)
-
-local results = TestEZ.TestBootstrap:run({modules.Rojo}, TestEZ.Reporters.TextReporter)
-
--- Did something go wrong?
-if results.failureCount > 0 then
-	os.exit(1)
-end

plugin/src/ApiContext.lua

@@ -1,152 +1,200 @@
+local Http = require(script.Parent.Parent.Http)
+local Log = require(script.Parent.Parent.Log)
 local Promise = require(script.Parent.Parent.Promise)
 
 local Config = require(script.Parent.Config)
+local Types = require(script.Parent.Types)
 local Version = require(script.Parent.Version)
-local Http = require(script.Parent.Http)
-local HttpError = require(script.Parent.HttpError)
 
-local ApiContext = {}
-ApiContext.__index = ApiContext
+local validateApiInfo = Types.ifEnabled(Types.ApiInfoResponse)
+local validateApiRead = Types.ifEnabled(Types.ApiReadResponse)
+local validateApiSubscribe = Types.ifEnabled(Types.ApiSubscribeResponse)
 
--- TODO: Audit cases of errors and create enum values for each of them.
-ApiContext.Error = {
-	ServerIdMismatch = "ServerIdMismatch",
-
-	-- The server gave an unexpected 400-category error, which may be the
-	-- client's fault.
-	ClientError = "ClientError",
-
-	-- The server gave an unexpected 500-category error, which may be the
-	-- server's fault.
-	ServerError = "ServerError",
-}
-
-setmetatable(ApiContext.Error, {
-	__index = function(_, key)
-		error("Invalid ApiContext.Error name " .. key, 2)
-	end
-})
+--[[
+	Returns a promise that will never resolve nor reject.
+]]
+local function hangingPromise()
+	return Promise.new(function() end)
+end
 
 local function rejectFailedRequests(response)
 	if response.code >= 400 then
-		if response.code < 500 then
-			return Promise.reject(ApiContext.Error.ClientError)
-		else
-			return Promise.reject(ApiContext.Error.ServerError)
-		end
+		local message = string.format("HTTP %s:\n%s", tostring(response.code), response.body)
+
+		return Promise.reject(message)
 	end
 
 	return response
 end
 
+local function rejectWrongProtocolVersion(infoResponseBody)
+	if infoResponseBody.protocolVersion ~= Config.protocolVersion then
+		local message = (
+			"Found a Rojo dev server, but it's using a different protocol version, and is incompatible." ..
+			"\nMake sure you have matching versions of both the Rojo plugin and server!" ..
+			"\n\nYour client is version %s, with protocol version %s. It expects server version %s." ..
+			"\nYour server is version %s, with protocol version %s." ..
+			"\n\nGo to https://github.com/rojo-rbx/rojo for more details."
+		):format(
+			Version.display(Config.version), Config.protocolVersion,
+			Config.expectedServerVersionString,
+			infoResponseBody.serverVersion, infoResponseBody.protocolVersion
+		)
+
+		return Promise.reject(message)
+	end
+
+	return Promise.resolve(infoResponseBody)
+end
+
+local function rejectWrongPlaceId(infoResponseBody)
+	if infoResponseBody.expectedPlaceIds ~= nil then
+		local foundId = false
+
+		for _, id in ipairs(infoResponseBody.expectedPlaceIds) do
+			if id == game.PlaceId then
+				foundId = true
+				break
+			end
+		end
+
+		if not foundId then
+			local idList = {}
+			for _, id in ipairs(infoResponseBody.expectedPlaceIds) do
+				table.insert(idList, "- " .. tostring(id))
+			end
+
+			local message = (
+				"Found a Rojo server, but its project is set to only be used with a specific list of places." ..
+				"\nYour place ID is %s, but needs to be one of these:" ..
+				"\n%s" ..
+				"\n\nTo change this list, edit 'servePlaceIds' in your .project.json file."
+			):format(
+				tostring(game.PlaceId),
+				table.concat(idList, "\n")
+			)
+
+			return Promise.reject(message)
+		end
+	end
+
+	return Promise.resolve(infoResponseBody)
+end
+
+local ApiContext = {}
+ApiContext.__index = ApiContext
+
 function ApiContext.new(baseUrl)
 	assert(type(baseUrl) == "string")
 
 	local self = {
-		baseUrl = baseUrl,
-		serverId = nil,
-		rootInstanceId = nil,
-		messageCursor = -1,
-		partitionRoutes = nil,
+		__baseUrl = baseUrl,
+		__sessionId = nil,
+		__messageCursor = -1,
+		__connected = true,
 	}
 
-	setmetatable(self, ApiContext)
-
-	return self
+	return setmetatable(self, ApiContext)
 end
 
-function ApiContext:onMessage(callback)
-	self.onMessageCallback = callback
+function ApiContext:__fmtDebug(output)
+	output:writeLine("ApiContext {{")
+	output:indent()
+
+	output:writeLine("Connected: {}", self.__connected)
+	output:writeLine("Base URL: {}", self.__baseUrl)
+	output:writeLine("Session ID: {}", self.__sessionId)
+	output:writeLine("Message Cursor: {}", self.__messageCursor)
+
+	output:unindent()
+	output:write("}")
+end
+
+function ApiContext:disconnect()
+	self.__connected = false
+end
+
+function ApiContext:setMessageCursor(index)
+	self.__messageCursor = index
 end
 
 function ApiContext:connect()
-	local url = ("%s/api/rojo"):format(self.baseUrl)
+	local url = ("%s/api/rojo"):format(self.__baseUrl)
 
 	return Http.get(url)
 		:andThen(rejectFailedRequests)
-		:andThen(function(response)
-			local body = response:json()
+		:andThen(Http.Response.json)
+		:andThen(rejectWrongProtocolVersion)
+		:andThen(function(body)
+			assert(validateApiInfo(body))
 
-			if body.protocolVersion ~= Config.protocolVersion then
-				local message = (
-					"Found a Rojo dev server, but it's using a different protocol version, and is incompatible." ..
-					"\nMake sure you have matching versions of both the Rojo plugin and server!" ..
-					"\n\nYour client is version %s, with protocol version %s. It expects server version %s." ..
-					"\nYour server is version %s, with protocol version %s." ..
-					"\n\nGo to https://github.com/LPGhatguy/rojo for more details."
-				):format(
-					Version.display(Config.version), Config.protocolVersion,
-					Config.expectedApiContextVersionString,
-					body.serverVersion, body.protocolVersion
-				)
-
-				return Promise.reject(message)
-			end
-
-			if body.expectedPlaceIds ~= nil then
-				local foundId = false
-
-				for _, id in ipairs(body.expectedPlaceIds) do
-					if id == game.PlaceId then
-						foundId = true
-						break
-					end
-				end
-
-				if not foundId then
-					local idList = {}
-					for _, id in ipairs(body.expectedPlaceIds) do
-						table.insert(idList, "- " .. tostring(id))
-					end
-
-					local message = (
-						"Found a Rojo server, but its project is set to only be used with a specific list of places." ..
-						"\nYour place ID is %s, but needs to be one of these:" ..
-						"\n%s" ..
-						"\n\nTo change this list, edit 'servePlaceIds' in roblox-project.json"
-					):format(
-						tostring(game.PlaceId),
-						table.concat(idList, "\n")
-					)
-
-					return Promise.reject(message)
-				end
-			end
-
-			self.serverId = body.serverId
-			self.partitionRoutes = body.partitions
-			self.rootInstanceId = body.rootInstanceId
+			return body
 		end)
-end
-
-function ApiContext:read(ids)
-	local url = ("%s/api/read/%s"):format(self.baseUrl, table.concat(ids, ","))
-
-	return Http.get(url)
-		:andThen(rejectFailedRequests)
-		:andThen(function(response)
-			local body = response:json()
-
-			if body.serverId ~= self.serverId then
-				return Promise.reject("Server changed ID")
-			end
+		:andThen(rejectWrongPlaceId)
+		:andThen(function(body)
+			self.__sessionId = body.sessionId
 
 			return body
 		end)
 end
 
-function ApiContext:retrieveMessages(initialCursor)
-	if initialCursor ~= nil then
-		self.messageCursor = initialCursor
+function ApiContext:read(ids)
+	local url = ("%s/api/read/%s"):format(self.__baseUrl, table.concat(ids, ","))
+
+	return Http.get(url)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(body)
+			if body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
+
+			assert(validateApiRead(body))
+
+			return body
+		end)
+end
+
+function ApiContext:write(patch)
+	local url = ("%s/api/write"):format(self.__baseUrl)
+
+	local body = {
+		sessionId = self.__sessionId,
+		removed = patch.removed,
+		updated = patch.updated,
+	}
+
+	-- 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.
+	if next(patch.added) ~= nil then
+		body.added = patch.added
 	end
 
-	local url = ("%s/api/subscribe/%s"):format(self.baseUrl, self.messageCursor)
+	body = Http.jsonEncode(body)
+
+	return Http.post(url, body)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(body)
+			Log.info("Write response: {:?}", body)
+
+			return body
+		end)
+end
+
+function ApiContext:retrieveMessages()
+	local url = ("%s/api/subscribe/%s"):format(self.__baseUrl, self.__messageCursor)
 
 	local function sendRequest()
 		return Http.get(url)
 			:catch(function(err)
-				if err.type == HttpError.Error.Timeout then
-					return sendRequest()
+				if err.type == Http.Error.Kind.Timeout then
+					if self.__connected then
+						return sendRequest()
+					else
+						return hangingPromise()
+					end
 				end
 
 				return Promise.reject(err)
@@ -155,14 +203,15 @@ function ApiContext:retrieveMessages(initialCursor)
 
 	return sendRequest()
 		:andThen(rejectFailedRequests)
-		:andThen(function(response)
-			local body = response:json()
-
-			if body.serverId ~= self.serverId then
+		:andThen(Http.Response.json)
+		:andThen(function(body)
+			if body.sessionId ~= self.__sessionId then
 				return Promise.reject("Server changed ID")
 			end
 
-			self.messageCursor = body.messageCursor
+			assert(validateApiSubscribe(body))
+
+			self:setMessageCursor(body.messageCursor)
 
 			return body.messages
 		end)

plugin/src/Assets.lua

@@ -1,11 +1,7 @@
+local strict = require(script.Parent.strict)
+
 local Assets = {
-	Sprites = {
-		WhiteCross = {
-			asset = "rbxassetid://2738712459",
-			offset = Vector2.new(190, 318),
-			size = Vector2.new(18, 18),
-		},
-	},
+	Sprites = {},
 	Slices = {
 		RoundBox = {
 			asset = "rbxassetid://2773204550",
@@ -24,11 +20,7 @@ local Assets = {
 }
 
 local function guardForTypos(name, map)
-	setmetatable(map, {
-		__index = function(_, key)
-			error(("%q is not a valid member of %s"):format(tostring(key), name), 2)
-		end
-	})
+	strict(name, map)
 
 	for key, child in pairs(map) do
 		if type(child) == "table" then

plugin/src/Components/App.lua

@@ -2,17 +2,21 @@ local Rojo = script:FindFirstAncestor("Rojo")
 local Plugin = Rojo.Plugin
 
 local Roact = require(Rojo.Roact)
+local Log = require(Rojo.Log)
 
+local ApiContext = require(Plugin.ApiContext)
 local Assets = require(Plugin.Assets)
 local Config = require(Plugin.Config)
 local DevSettings = require(Plugin.DevSettings)
-local Logging = require(Plugin.Logging)
-local Session = require(Plugin.Session)
+local ServeSession = require(Plugin.ServeSession)
 local Version = require(Plugin.Version)
 local preloadAssets = require(Plugin.preloadAssets)
+local strict = require(Plugin.strict)
 
 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 e = Roact.createElement
 
@@ -26,7 +30,7 @@ local function showUpgradeMessage(lastVersion)
 		Version.display(Config.version), Config.expectedServerVersionString
 	)
 
-	Logging.info(message)
+	Log.info(message)
 end
 
 --[[
@@ -52,26 +56,23 @@ local function checkUpgrade(plugin)
 	plugin:SetSetting("LastRojoVersion", Config.version)
 end
 
-local SessionStatus = {
-	Disconnected = "Disconnected",
+local AppStatus = strict("AppStatus", {
+	NotStarted = "NotStarted",
+	Connecting = "Connecting",
 	Connected = "Connected",
-}
-
-setmetatable(SessionStatus, {
-	__index = function(_, key)
-		error(("%q is not a valid member of SessionStatus"):format(tostring(key)), 2)
-	end,
+	Error = "Error",
 })
 
 local App = Roact.Component:extend("App")
 
 function App:init()
 	self:setState({
-		sessionStatus = SessionStatus.Disconnected,
+		appStatus = AppStatus.NotStarted,
+		errorMessage = nil,
 	})
 
 	self.signals = {}
-	self.currentSession = nil
+	self.serveSession = nil
 
 	self.displayedVersion = DevSettings:isEnabled()
 		and Config.codename
@@ -96,7 +97,7 @@ function App:init()
 		360, 190 -- Minimum size
 	)
 
-	self.dockWidget = self.props.plugin:CreateDockWidgetPluginGui("Rojo-0.5.x", widgetInfo)
+	self.dockWidget = self.props.plugin:CreateDockWidgetPluginGui("Rojo-" .. self.displayedVersion, widgetInfo)
 	self.dockWidget.Name = "Rojo " .. self.displayedVersion
 	self.dockWidget.Title = "Rojo " .. self.displayedVersion
 	self.dockWidget.AutoLocalize = false
@@ -107,56 +108,91 @@ function App:init()
 	end)
 end
 
+function App:startSession(address, port)
+	Log.trace("Starting new session")
+
+	local baseUrl = ("http://%s:%s"):format(address, port)
+	self.serveSession = ServeSession.new({
+		apiContext = ApiContext.new(baseUrl),
+	})
+
+	self.serveSession:onStatusChanged(function(status, details)
+		if status == ServeSession.Status.Connecting then
+			self:setState({
+				appStatus = AppStatus.Connecting,
+			})
+		elseif status == ServeSession.Status.Connected then
+			self:setState({
+				appStatus = AppStatus.Connected,
+			})
+		elseif status == ServeSession.Status.Disconnected then
+			self.serveSession = nil
+
+			-- Details being present indicates that this
+			-- disconnection was from an error.
+			if details ~= nil then
+				Log.warn("Disconnected from an error: {}", details)
+
+				self:setState({
+					appStatus = AppStatus.Error,
+					errorMessage = tostring(details),
+				})
+			else
+				self:setState({
+					appStatus = AppStatus.NotStarted,
+				})
+			end
+		end
+	end)
+
+	self.serveSession:start()
+end
+
 function App:render()
 	local children
 
-	if self.state.sessionStatus == SessionStatus.Connected then
-		children = {
-			ConnectionActivePanel = e(ConnectionActivePanel, {
-				stopSession = function()
-					Logging.trace("Disconnecting session")
-
-					self.currentSession:disconnect()
-					self.currentSession = nil
-					self:setState({
-						sessionStatus = SessionStatus.Disconnected,
-					})
-
-					Logging.trace("Session terminated by user")
-				end,
-			}),
-		}
-	elseif self.state.sessionStatus == SessionStatus.Disconnected then
+	if self.state.appStatus == AppStatus.NotStarted then
 		children = {
 			ConnectPanel = e(ConnectPanel, {
 				startSession = function(address, port)
-					Logging.trace("Starting new session")
-
-					local success, session = Session.new({
-						address = address,
-						port = port,
-						onError = function(message)
-							Logging.warn("Rojo session terminated because of an error:\n%s", tostring(message))
-							self.currentSession = nil
-
-							self:setState({
-								sessionStatus = SessionStatus.Disconnected,
-							})
-						end
-					})
-
-					if success then
-						self.currentSession = session
-						self:setState({
-							sessionStatus = SessionStatus.Connected,
-						})
-					end
+					self:startSession(address, port)
 				end,
 				cancel = function()
-					Logging.trace("Canceling session configuration")
+					Log.trace("Canceling session configuration")
 
 					self:setState({
-						sessionStatus = SessionStatus.Disconnected,
+						appStatus = AppStatus.NotStarted,
+					})
+				end,
+			}),
+		}
+	elseif self.state.appStatus == AppStatus.Connecting then
+		children = {
+			ConnectingPanel = Roact.createElement(ConnectingPanel),
+		}
+	elseif self.state.appStatus == AppStatus.Connected then
+		children = {
+			ConnectionActivePanel = e(ConnectionActivePanel, {
+				stopSession = function()
+					Log.trace("Disconnecting session")
+
+					self.serveSession:stop()
+					self.serveSession = nil
+					self:setState({
+						appStatus = AppStatus.NotStarted,
+					})
+
+					Log.trace("Session terminated by user")
+				end,
+			}),
+		}
+	elseif self.state.appStatus == AppStatus.Error then
+		children = {
+			ErrorPanel = Roact.createElement(ErrorPanel, {
+				errorMessage = self.state.errorMessage,
+				onDismiss = function()
+					self:setState({
+						appStatus = AppStatus.NotStarted,
 					})
 				end,
 			}),
@@ -169,16 +205,16 @@ function App:render()
 end
 
 function App:didMount()
-	Logging.trace("Rojo %s initializing", self.displayedVersion)
+	Log.trace("Rojo {} initializing", self.displayedVersion)
 
 	checkUpgrade(self.props.plugin)
 	preloadAssets()
 end
 
 function App:willUnmount()
-	if self.currentSession ~= nil then
-		self.currentSession:disconnect()
-		self.currentSession = nil
+	if self.serveSession ~= nil then
+		self.serveSession:stop()
+		self.serveSession = nil
 	end
 
 	for _, signal in pairs(self.signals) do

plugin/src/Components/ConnectingPanel.lua

@@ -0,0 +1,34 @@
+local Roact = require(script:FindFirstAncestor("Rojo").Roact)
+
+local Plugin = script:FindFirstAncestor("Plugin")
+
+local Theme = require(Plugin.Theme)
+
+local Panel = require(Plugin.Components.Panel)
+local FitText = require(Plugin.Components.FitText)
+
+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),
+		}),
+
+		Text = e(FitText, {
+			Padding = Vector2.new(12, 6),
+			Font = Theme.ButtonFont,
+			TextSize = 18,
+			Text = "Connecting...",
+			TextColor3 = Theme.PrimaryColor,
+			BackgroundTransparency = 1,
+		}),
+	})
+end
+
+return ConnectingPanel

plugin/src/Components/ErrorPanel.lua

@@ -0,0 +1,69 @@
+local Roact = require(script:FindFirstAncestor("Rojo").Roact)
+
+local Plugin = script:FindFirstAncestor("Plugin")
+
+local Theme = require(Plugin.Theme)
+
+local Panel = require(Plugin.Components.Panel)
+local FitText = require(Plugin.Components.FitText)
+local FitScrollingFrame = require(Plugin.Components.FitScrollingFrame)
+local FormButton = require(Plugin.Components.FormButton)
+
+local e = Roact.createElement
+
+local BUTTON_HEIGHT = 60
+local HOR_PADDING = 8
+
+local ErrorPanel = Roact.Component:extend("ErrorPanel")
+
+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,
+			}),
+		}),
+
+		DismissButton = e(FormButton, {
+			layoutOrder = 2,
+			text = "Dismiss",
+			secondary = true,
+			onClick = function()
+				onDismiss()
+			end,
+		}),
+	})
+end
+
+return ErrorPanel

plugin/src/Components/FitScrollingFrame.lua

@@ -0,0 +1,33 @@
+local Roact = require(script:FindFirstAncestor("Rojo").Roact)
+
+local Dictionary = require(script.Parent.Parent.Dictionary)
+
+local e = Roact.createElement
+
+local FitScrollingFrame = Roact.Component:extend("FitScrollingFrame")
+
+function FitScrollingFrame:init()
+	self.sizeBinding, self.setSize = Roact.createBinding(UDim2.new())
+end
+
+function FitScrollingFrame:render()
+	local containerProps = self.props.containerProps
+	local layoutProps = self.props.layoutProps
+
+	local children = Dictionary.merge(self.props[Roact.Children], {
+		["$Layout"] = e("UIListLayout", Dictionary.merge({
+			SortOrder = Enum.SortOrder.LayoutOrder,
+			[Roact.Change.AbsoluteContentSize] = function(instance)
+				self.setSize(UDim2.new(0, 0, 0, instance.AbsoluteContentSize.Y))
+			end,
+		}, layoutProps)),
+	})
+
+	local fullContainerProps = Dictionary.merge(containerProps, {
+		CanvasSize = self.sizeBinding,
+	})
+
+	return e("ScrollingFrame", fullContainerProps, children)
+end
+
+return FitScrollingFrame

plugin/src/Components/FitText.lua

@@ -9,6 +9,7 @@ local e = Roact.createElement
 local FitText = Roact.Component:extend("FitText")
 
 function FitText:init()
+	self.ref = Roact.createRef()
 	self.sizeBinding, self.setSize = Roact.createBinding(UDim2.new())
 end
 
@@ -16,10 +17,15 @@ function FitText:render()
 	local kind = self.props.Kind or "TextLabel"
 
 	local containerProps = Dictionary.merge(self.props, {
+		FitAxis = Dictionary.None,
 		Kind = Dictionary.None,
 		Padding = Dictionary.None,
 		MinSize = Dictionary.None,
-		Size = self.sizeBinding
+		Size = self.sizeBinding,
+		[Roact.Ref] = self.ref,
+		[Roact.Change.AbsoluteSize] = function()
+			self:updateTextMeasurements()
+		end
 	})
 
 	return e(kind, containerProps)
@@ -36,15 +42,45 @@ end
 function FitText:updateTextMeasurements()
 	local minSize = self.props.MinSize or Vector2.new(0, 0)
 	local padding = self.props.Padding or Vector2.new(0, 0)
+	local fitAxis = self.props.FitAxis or "XY"
+	local baseSize = self.props.Size
 
 	local text = self.props.Text or ""
 	local font = self.props.Font or Enum.Font.Legacy
 	local textSize = self.props.TextSize or 12
 
-	local measuredText = TextService:GetTextSize(text, textSize, font, Vector2.new(9e6, 9e6))
-	local totalSize = UDim2.new(
-		0, math.max(minSize.X, padding.X * 2 + measuredText.X),
-		0, math.max(minSize.Y, padding.Y * 2 + measuredText.Y))
+	local containerSize = self.ref.current.AbsoluteSize
+
+	local textBounds
+
+	if fitAxis == "XY" then
+		textBounds = Vector2.new(9e6, 9e6)
+	elseif fitAxis == "X" then
+		textBounds = Vector2.new(9e6, containerSize.Y - padding.Y * 2)
+	elseif fitAxis == "Y" then
+		textBounds = Vector2.new(containerSize.X - padding.X * 2, 9e6)
+	end
+
+	local measuredText = TextService:GetTextSize(text, textSize, font, textBounds)
+
+	local computedX = math.max(minSize.X, padding.X * 2 + measuredText.X)
+	local computedY = math.max(minSize.Y, padding.Y * 2 + measuredText.Y)
+
+	local totalSize
+
+	if fitAxis == "XY" then
+		totalSize = UDim2.new(
+			0, computedX,
+			0, computedY)
+	elseif fitAxis == "X" then
+		totalSize = UDim2.new(
+			0, computedX,
+			baseSize.Y.Scale, baseSize.Y.Offset)
+	elseif fitAxis == "Y" then
+		totalSize = UDim2.new(
+			baseSize.X.Scale, baseSize.X.Offset,
+			0, computedY)
+	end
 
 	self.setSize(totalSize)
 end

plugin/src/Components/RojoFooter.lua

@@ -8,8 +8,6 @@ local Version = require(Plugin.Version)
 local Assets = require(Plugin.Assets)
 local Theme = require(Plugin.Theme)
 
-local FitText = require(Plugin.Components.FitText)
-
 local e = Roact.createElement
 
 local RojoFooter = Roact.Component:extend("RojoFooter")

plugin/src/Config.lua

@@ -1,8 +1,13 @@
-return {
+local strict = require(script.Parent.strict)
+
+local isDevBuild = script.Parent.Parent:FindFirstChild("ROJO_DEV_BUILD") ~= nil
+
+return strict("Config", {
+	isDevBuild = isDevBuild,
 	codename = "Epiphany",
-	version = {0, 5, 3},
-	expectedServerVersionString = "0.5.0 or newer",
-	protocolVersion = 2,
+	version = {0, 6, 0, "-alpha.1"},
+	expectedServerVersionString = "0.6.0 or newer",
+	protocolVersion = 3,
 	defaultHost = "localhost",
 	defaultPort = 34872,
-}
+})

plugin/src/DevSettings.lua

@@ -6,13 +6,15 @@ local Environment = {
 	Test = "Test",
 }
 
+local DEFAULT_ENVIRONMENT = Config.isDevBuild and Environment.Dev or Environment.User
+
 local VALUES = {
 	LogLevel = {
 		type = "IntValue",
 		values = {
 			[Environment.User] = 2,
-			[Environment.Dev] = 3,
-			[Environment.Test] = 3,
+			[Environment.Dev] = 4,
+			[Environment.Test] = 4,
 		},
 	},
 	TypecheckingEnabled = {
@@ -23,6 +25,14 @@ local VALUES = {
 			[Environment.Test] = true,
 		},
 	},
+	UnstableTwoWaySync = {
+		type = "BoolValue",
+		values = {
+			[Environment.User] = false,
+			[Environment.Dev] = false,
+			[Environment.Test] = false,
+		},
+	},
 }
 
 local CONTAINER_NAME = "RojoDevSettings" .. Config.codename
@@ -33,6 +43,16 @@ end
 
 local valueContainer = getValueContainer()
 
+game.ChildAdded:Connect(function(child)
+	local success, name = pcall(function()
+		return child.Name
+	end)
+
+	if success and name == CONTAINER_NAME then
+		valueContainer = child
+	end
+end)
+
 local function getStoredValue(name)
 	if valueContainer == nil then
 		return nil
@@ -84,7 +104,7 @@ local function getValue(name)
 		return stored
 	end
 
-	return VALUES[name].values[Environment.User]
+	return VALUES[name].values[DEFAULT_ENVIRONMENT]
 end
 
 local DevSettings = {}
@@ -120,6 +140,10 @@ function DevSettings:shouldTypecheck()
 	return getValue("TypecheckingEnabled")
 end
 
+function DevSettings:twoWaySyncEnabled()
+	return getValue("UnstableTwoWaySync")
+end
+
 function _G.ROJO_DEV_CREATE()
 	DevSettings:createDevSettings()
 end

plugin/src/Http.lua

@@ -1,75 +0,0 @@
-local HttpService = game:GetService("HttpService")
-
-local Promise = require(script.Parent.Parent.Promise)
-
-local Logging = require(script.Parent.Logging)
-local HttpError = require(script.Parent.HttpError)
-local HttpResponse = require(script.Parent.HttpResponse)
-
-local lastRequestId = 0
-
--- TODO: Factor out into separate library, especially error handling
-local Http = {}
-
-function Http.get(url)
-	local requestId = lastRequestId + 1
-	lastRequestId = requestId
-
-	Logging.trace("GET(%d) %s", requestId, url)
-
-	return Promise.new(function(resolve, reject)
-		coroutine.wrap(function()
-			local success, response = pcall(function()
-				return HttpService:RequestAsync({
-					Url = url,
-					Method = "GET",
-				})
-			end)
-
-			if success then
-				Logging.trace("Request %d success: status code %s", requestId, response.StatusCode)
-				resolve(HttpResponse.fromRobloxResponse(response))
-			else
-				Logging.trace("Request %d failure: %s", requestId, response)
-				reject(HttpError.fromErrorString(response))
-			end
-		end)()
-	end)
-end
-
-function Http.post(url, body)
-	local requestId = lastRequestId + 1
-	lastRequestId = requestId
-
-	Logging.trace("POST(%d) %s\n%s", requestId, url, body)
-
-	return Promise.new(function(resolve, reject)
-		coroutine.wrap(function()
-			local success, response = pcall(function()
-				return HttpService:RequestAsync({
-					Url = url,
-					Method = "POST",
-					Body = body,
-				})
-			end)
-
-			if success then
-				Logging.trace("Request %d success: status code %s", requestId, response.StatusCode)
-				resolve(HttpResponse.fromRobloxResponse(response))
-			else
-				Logging.trace("Request %d failure: %s", requestId, response)
-				reject(HttpError.fromErrorString(response))
-			end
-		end)()
-	end)
-end
-
-function Http.jsonEncode(object)
-	return HttpService:JSONEncode(object)
-end
-
-function Http.jsonDecode(source)
-	return HttpService:JSONDecode(source)
-end
-
-return Http

plugin/src/InstanceMap.lua

@@ -1,4 +1,4 @@
-local Logging = require(script.Parent.Logging)
+local Log = require(script.Parent.Parent.Log)
 
 --[[
 	A bidirectional map between instance IDs and Roblox instances. It lets us
@@ -9,39 +9,79 @@ local Logging = require(script.Parent.Logging)
 local InstanceMap = {}
 InstanceMap.__index = InstanceMap
 
-function InstanceMap.new()
+function InstanceMap.new(onInstanceChanged)
 	local self = {
 		fromIds = {},
 		fromInstances = {},
+		instancesToSignal = {},
+		onInstanceChanged = onInstanceChanged,
 	}
 
 	return setmetatable(self, InstanceMap)
 end
 
+--[[
+	Disconnect all connections and release all instance references.
+]]
+function InstanceMap:stop()
+	-- I think this is safe.
+	for instance in pairs(self.fromInstances) do
+		self:removeInstance(instance)
+	end
+end
+
+function InstanceMap:__fmtDebug(output)
+	output:writeLine("InstanceMap {{")
+	output:indent()
+
+	-- Collect all of the entries in the InstanceMap and sort them by their
+	-- label, which helps make our output deterministic.
+	local entries = {}
+	for id, instance in pairs(self.fromIds) do
+		local label = string.format("%s (%s)", instance:GetFullName(), instance.ClassName)
+
+		table.insert(entries, {id, label})
+	end
+
+	table.sort(entries, function(a, b)
+		return a[2] < b[2]
+	end)
+
+	for _, entry in ipairs(entries) do
+		output:writeLine("{}: {}", entry[1], entry[2])
+	end
+
+	output:unindent()
+	output:write("}")
+end
+
 function InstanceMap:insert(id, instance)
 	self.fromIds[id] = instance
 	self.fromInstances[instance] = id
+	self:__connectSignals(instance)
 end
 
 function InstanceMap:removeId(id)
 	local instance = self.fromIds[id]
 
 	if instance ~= nil then
+		self:__disconnectSignals(instance)
 		self.fromIds[id] = nil
 		self.fromInstances[instance] = nil
 	else
-		Logging.warn("Attempted to remove nonexistant ID %s", tostring(id))
+		Log.warn("Attempted to remove nonexistant ID {}", id)
 	end
 end
 
 function InstanceMap:removeInstance(instance)
 	local id = self.fromInstances[instance]
+	self:__disconnectSignals(instance)
 
 	if id ~= nil then
 		self.fromInstances[instance] = nil
 		self.fromIds[id] = nil
 	else
-		Logging.warn("Attempted to remove nonexistant instance %s", tostring(instance))
+		Log.warn("Attempted to remove nonexistant instance {}", instance)
 	end
 end
 
@@ -51,7 +91,7 @@ function InstanceMap:destroyInstance(instance)
 	if id ~= nil then
 		self:destroyId(id)
 	else
-		Logging.warn("Attempted to destroy untracked instance %s", tostring(instance))
+		Log.warn("Attempted to destroy untracked instance {}", instance)
 	end
 end
 
@@ -74,7 +114,59 @@ function InstanceMap:destroyId(id)
 
 		instance:Destroy()
 	else
-		Logging.warn("Attempted to destroy nonexistant ID %s", tostring(id))
+		Log.warn("Attempted to destroy nonexistant ID {}", id)
+	end
+end
+
+function InstanceMap:__connectSignals(instance)
+	-- ValueBase instances have an overriden version of the Changed signal that
+	-- only detects changes to their Value property.
+	--
+	-- We can instead connect listener to each individual property that we care
+	-- about on those objects (Name and Value) to emulate the same idea.
+	if instance:IsA("ValueBase") then
+		local signals = {
+			instance:GetPropertyChangedSignal("Name"):Connect(function()
+				self:__maybeFireInstanceChanged(instance, "Name")
+			end),
+
+			instance:GetPropertyChangedSignal("Value"):Connect(function()
+				self:__maybeFireInstanceChanged(instance, "Value")
+			end),
+		}
+
+		self.instancesToSignal[instance] = signals
+	else
+		self.instancesToSignal[instance] = instance.Changed:Connect(function(propertyName)
+			self:__maybeFireInstanceChanged(instance, propertyName)
+		end)
+	end
+end
+
+function InstanceMap:__maybeFireInstanceChanged(instance, propertyName)
+	Log.trace("{}.{} changed", instance:GetFullName(), propertyName)
+
+	if self.onInstanceChanged ~= nil then
+		self.onInstanceChanged(instance, propertyName)
+	end
+end
+
+function InstanceMap:__disconnectSignals(instance)
+	local signals = self.instancesToSignal[instance]
+
+	if signals ~= nil then
+		-- In most cases, we only have a single signal, so we avoid keeping
+		-- around the extra table. ValueBase objects force us to use multiple
+		-- signals to emulate the Instance.Changed event, however.
+		if typeof(signals) == "table" then
+			for _, signal in ipairs(signals) do
+				signal:Disconnect()
+			end
+		else
+			signals:Disconnect()
+		end
+
+		self.instancesToSignal[instance] = nil
 	end
 end
 

plugin/src/Reconciler.lua

@@ -1,236 +1,401 @@
+--[[
+	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 InstanceMap = require(script.Parent.InstanceMap)
-local Logging = require(script.Parent.Logging)
-local setCanonicalProperty = require(script.Parent.setCanonicalProperty)
-local rojoValueToRobloxValue = require(script.Parent.rojoValueToRobloxValue)
 local Types = require(script.Parent.Types)
+local invariant = require(script.Parent.invariant)
+local getCanonicalProperty = require(script.Parent.getCanonicalProperty)
+local setCanonicalProperty = require(script.Parent.setCanonicalProperty)
 
-local function setParent(instance, newParent)
+--[[
+	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()
+function Reconciler.new(instanceMap)
 	local self = {
-		instanceMap = InstanceMap.new(),
+		-- Tracks all of the instances known by the reconciler by ID.
+		__instanceMap = instanceMap,
 	}
 
 	return setmetatable(self, Reconciler)
 end
 
-function Reconciler:applyUpdate(requestedIds, virtualInstancesById)
-	-- This function may eventually be asynchronous; it will require calls to
-	-- the server to resolve instances that don't exist yet.
-	local visitedIds = {}
+--[[
+	See Reconciler:__hydrateInternal().
+]]
+function Reconciler:hydrate(apiInstances, id, instance)
+	local hydratePatch = {
+		removed = {},
+		added = {},
+		updated = {},
+	}
 
-	for _, id in ipairs(requestedIds) do
-		self:__applyUpdatePiece(id, visitedIds, virtualInstancesById)
+	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
 
-local reconcileSchema = Types.ifEnabled(t.tuple(
-	t.map(t.string, Types.VirtualInstance),
-	t.string,
-	t.Instance
-))
 --[[
-	Update an existing instance, including its properties and children, to match
-	the given information.
+	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:reconcile(virtualInstancesById, id, instance)
-	assert(reconcileSchema(virtualInstancesById, id, instance))
-
-	local virtualInstance = virtualInstancesById[id]
-
-	-- If an instance changes ClassName, we assume it's very different. That's
-	-- not always the case!
-	if virtualInstance.ClassName ~= instance.ClassName then
-		Logging.trace("Switching to reify for %s because ClassName is different", instance:GetFullName())
-
-		-- TODO: Preserve existing children instead?
-		local parent = instance.Parent
-		self.instanceMap:destroyId(id)
-		return self:__reify(virtualInstancesById, id, parent)
+function Reconciler:encodeApiValue(value)
+	if typeof(value) == "string" then
+		return true, {
+			Type = "String",
+			Value = value,
+		}
 	end
 
-	self.instanceMap:insert(id, instance)
+	return false
+end
 
-	-- Some instances don't like being named, even if their name already matches
-	setCanonicalProperty(instance, "Name", virtualInstance.Name)
+--[[
+	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))
 
-	for key, value in pairs(virtualInstance.Properties) do
-		setCanonicalProperty(instance, key, rojoValueToRobloxValue(value))
+	-- 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()
 
-	local unvisitedExistingChildren = {}
-	for _, child in ipairs(existingChildren) do
-		unvisitedExistingChildren[child] = true
+	-- 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(virtualInstance.Children) do
-		local childData = virtualInstancesById[childId]
+	for _, childId in ipairs(apiInstance.Children) do
+		local apiChild = apiInstances[childId]
 
-		local existingChildInstance
-		for instance in pairs(unvisitedExistingChildren) do
-			local ok, name, className = pcall(function()
-				return instance.Name, instance.ClassName
-			end)
+		local childInstance
 
-			if ok then
-				if name == childData.Name and className == childData.ClassName then
-					existingChildInstance = instance
+		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 existingChildInstance ~= nil then
-			unvisitedExistingChildren[existingChildInstance] = nil
-			self:reconcile(virtualInstancesById, childId, existingChildInstance)
+		if childInstance ~= nil then
+			-- We found an instance that matches the instance from the API, yay!
+			self:__hydrateInternal(apiInstances, childId, childInstance, hydratePatch)
 		else
-			Logging.trace(
-				"Switching to reify for %s.%s because it does not exist",
-				instance:GetFullName(),
-				virtualInstancesById[childId].Name
-			)
-
-			self:__reify(virtualInstancesById, childId, instance)
+			markIdAdded(childId)
 		end
 	end
 
-	local shouldClearUnknown = self:__shouldClearUnknownChildren(virtualInstance)
-
-	for existingChildInstance in pairs(unvisitedExistingChildren) do
-		local childId = self.instanceMap.fromInstances[existingChildInstance]
-
-		if childId == nil then
-			if shouldClearUnknown then
-				existingChildInstance:Destroy()
+	-- 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
-		else
-			self.instanceMap:destroyInstance(existingChildInstance)
 		end
 	end
-
-	-- The root instance of a project won't have a parent, like the DataModel,
-	-- so we need to be careful here.
-	if virtualInstance.Parent ~= nil then
-		local parent = self.instanceMap.fromIds[virtualInstance.Parent]
-
-		if parent == nil then
-			Logging.info("Instance %s wanted parent of %s", tostring(id), tostring(virtualInstance.Parent))
-			error("Rojo bug: During reconciliation, an instance referred to an instance ID as parent that does not exist.")
-		end
-
-		-- Some instances, like services, don't like having their Parent
-		-- property poked, even if we're setting it to the same value.
-		setParent(instance, parent)
-	end
-
-	return instance
 end
 
-function Reconciler:__shouldClearUnknownChildren(virtualInstance)
-	if virtualInstance.Metadata ~= nil then
-		return not virtualInstance.Metadata.ignoreUnknownInstances
+function Reconciler:__shouldClearUnknownChildren(apiInstance)
+	if apiInstance.Metadata ~= nil then
+		return not apiInstance.Metadata.ignoreUnknownInstances
 	else
 		return true
 	end
 end
 
-local reifySchema = Types.ifEnabled(t.tuple(
-	t.map(t.string, Types.VirtualInstance),
-	t.string,
-	t.Instance
-))
-
-function Reconciler:__reify(virtualInstancesById, id, parent)
-	assert(reifySchema(virtualInstancesById, id, parent))
-
-	local virtualInstance = virtualInstancesById[id]
-
-	local ok, instance = pcall(function()
-		return Instance.new(virtualInstance.ClassName)
-	end)
-
-	if not ok then
-		error(("Couldn't create an Instance of type %q, a child of %s"):format(virtualInstance.ClassName, parent:GetFullName()))
-	end
-
-	for key, value in pairs(virtualInstance.Properties) do
-		setCanonicalProperty(instance, key, rojoValueToRobloxValue(value))
-	end
-
-	setCanonicalProperty(instance, "Name", virtualInstance.Name)
-
-	for _, childId in ipairs(virtualInstance.Children) do
-		self:__reify(virtualInstancesById, childId, instance)
-	end
-
-	setParent(instance, parent)
-	self.instanceMap:insert(id, instance)
-
-	return instance
-end
-
-local applyUpdatePieceSchema = Types.ifEnabled(t.tuple(
-	t.string,
-	t.map(t.string, t.boolean),
-	t.map(t.string, Types.VirtualInstance)
-))
-
-function Reconciler:__applyUpdatePiece(id, visitedIds, virtualInstancesById)
-	assert(applyUpdatePieceSchema(id, visitedIds, virtualInstancesById))
-
-	if visitedIds[id] then
-		return
-	end
-
-	visitedIds[id] = true
-
-	local virtualInstance = virtualInstancesById[id]
-	local instance = self.instanceMap.fromIds[id]
-
-	-- The instance was deleted in this update
-	if virtualInstance == nil then
-		self.instanceMap:destroyId(id)
-		return
-	end
-
-	-- An instance we know about was updated
-	if instance ~= nil then
-		self:reconcile(virtualInstancesById, id, instance)
-		return instance
-	end
-
-	-- If the instance's parent already exists, we can stick it there
-	local parentInstance = self.instanceMap.fromIds[virtualInstance.Parent]
-	if parentInstance ~= nil then
-		self:__reify(virtualInstancesById, id, parentInstance)
-		return
-	end
-
-	-- Otherwise, we can check if this response payload contained the parent and
-	-- work from there instead.
-	local parentData = virtualInstancesById[virtualInstance.Parent]
-	if parentData ~= nil then
-		if visitedIds[virtualInstance.Parent] then
-			error("Rojo bug: An instance was present and marked as visited but its instance was missing")
-		end
-
-		self:__applyUpdatePiece(virtualInstance.Parent, visitedIds, virtualInstancesById)
-		return
-	end
-
-	Logging.trace("Instance ID %s, parent ID %s", tostring(id), tostring(virtualInstance.Parent))
-	error("Rojo NYI: Instances with parents that weren't mentioned in an update payload")
-end
-
 return Reconciler

plugin/src/Reconciler.spec.lua

@@ -1,218 +0,0 @@
-local Reconciler = require(script.Parent.Reconciler)
-
-return function()
-	it("should leave instances alone if there's nothing specified", function()
-		local instance = Instance.new("Folder")
-		instance.Name = "TestFolder"
-
-		local instanceId = "test-id"
-		local virtualInstancesById = {
-			[instanceId] = {
-				Name = "TestFolder",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-		}
-
-		local reconciler = Reconciler.new()
-		reconciler:reconcile(virtualInstancesById, instanceId, instance)
-	end)
-
-	it("should assign names from virtual instances", function()
-		local instance = Instance.new("Folder")
-		instance.Name = "InitialName"
-
-		local instanceId = "test-id"
-		local virtualInstancesById = {
-			[instanceId] = {
-				Name = "NewName",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-		}
-
-		local reconciler = Reconciler.new()
-		reconciler:reconcile(virtualInstancesById, instanceId, instance)
-
-		expect(instance.Name).to.equal("NewName")
-	end)
-
-	it("should assign properties from virtual instances", function()
-		local instance = Instance.new("IntValue")
-		instance.Name = "TestValue"
-		instance.Value = 5
-
-		local instanceId = "test-id"
-		local virtualInstancesById = {
-			[instanceId] = {
-				Name = "TestValue",
-				ClassName = "IntValue",
-				Children = {},
-				Properties = {
-					Value = {
-						Type = "Int32",
-						Value = 9
-					}
-				},
-			},
-		}
-
-		local reconciler = Reconciler.new()
-		reconciler:reconcile(virtualInstancesById, instanceId, instance)
-
-		expect(instance.Value).to.equal(9)
-	end)
-
-	it("should wipe unknown children by default", function()
-		local parent = Instance.new("Folder")
-		parent.Name = "Parent"
-
-		local child = Instance.new("Folder")
-		child.Name = "Child"
-
-		local parentId = "test-id"
-		local virtualInstancesById = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-		}
-
-		local reconciler = Reconciler.new()
-		reconciler:reconcile(virtualInstancesById, parentId, parent)
-
-		expect(#parent:GetChildren()).to.equal(0)
-	end)
-
-	it("should preserve unknown children if ignoreUnknownInstances is set", function()
-		local parent = Instance.new("Folder")
-		parent.Name = "Parent"
-
-		local child = Instance.new("Folder")
-		child.Parent = parent
-		child.Name = "Child"
-
-		local parentId = "test-id"
-		local virtualInstancesById = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-				Metadata = {
-					ignoreUnknownInstances = true,
-				},
-			},
-		}
-
-		local reconciler = Reconciler.new()
-		reconciler:reconcile(virtualInstancesById, parentId, parent)
-
-		expect(child.Parent).to.equal(parent)
-		expect(#parent:GetChildren()).to.equal(1)
-	end)
-
-	it("should remove known removed children", function()
-		local parent = Instance.new("Folder")
-		parent.Name = "Parent"
-
-		local child = Instance.new("Folder")
-		child.Parent = parent
-		child.Name = "Child"
-
-		local parentId = "parent-id"
-		local childId = "child-id"
-
-		local reconciler = Reconciler.new()
-
-		local virtualInstancesById = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {childId},
-				Properties = {},
-			},
-			[childId] = {
-				Name = "Child",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-		}
-		reconciler:reconcile(virtualInstancesById, parentId, parent)
-
-		expect(child.Parent).to.equal(parent)
-		expect(#parent:GetChildren()).to.equal(1)
-
-		local newVirtualInstances = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-			[childId] = nil,
-		}
-		reconciler:reconcile(newVirtualInstances, parentId, parent)
-
-		expect(child.Parent).to.equal(nil)
-		expect(#parent:GetChildren()).to.equal(0)
-	end)
-
-	it("should remove known removed children if ignoreUnknownInstances is set", function()
-		local parent = Instance.new("Folder")
-		parent.Name = "Parent"
-
-		local child = Instance.new("Folder")
-		child.Parent = parent
-		child.Name = "Child"
-
-		local parentId = "parent-id"
-		local childId = "child-id"
-
-		local reconciler = Reconciler.new()
-
-		local virtualInstancesById = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {childId},
-				Properties = {},
-				Metadata = {
-					ignoreUnknownInstances = true,
-				},
-			},
-			[childId] = {
-				Name = "Child",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-			},
-		}
-		reconciler:reconcile(virtualInstancesById, parentId, parent)
-
-		expect(child.Parent).to.equal(parent)
-		expect(#parent:GetChildren()).to.equal(1)
-
-		local newVirtualInstances = {
-			[parentId] = {
-				Name = "Parent",
-				ClassName = "Folder",
-				Children = {},
-				Properties = {},
-				Metadata = {
-					ignoreUnknownInstances = true,
-				},
-			},
-			[childId] = nil,
-		}
-		reconciler:reconcile(newVirtualInstances, parentId, parent)
-
-		expect(child.Parent).to.equal(nil)
-		expect(#parent:GetChildren()).to.equal(0)
-	end)
-end

plugin/src/ServeSession.lua

@@ -0,0 +1,203 @@
+local Log = require(script.Parent.Parent.Log)
+local Fmt = require(script.Parent.Parent.Fmt)
+local t = require(script.Parent.Parent.t)
+
+local DevSettings = require(script.Parent.DevSettings)
+local InstanceMap = require(script.Parent.InstanceMap)
+local Reconciler = require(script.Parent.Reconciler)
+local strict = require(script.Parent.strict)
+
+local Status = strict("Session.Status", {
+	NotStarted = "NotStarted",
+	Connecting = "Connecting",
+	Connected = "Connected",
+	Disconnected = "Disconnected",
+})
+
+local function debugPatch(patch)
+	return Fmt.debugify(patch, function(patch, output)
+		output:writeLine("Patch {{")
+		output:indent()
+
+		for removed in ipairs(patch.removed) do
+			output:writeLine("Remove ID {}", removed)
+		end
+
+		for id, added in pairs(patch.added) do
+			output:writeLine("Add ID {} {:#?}", id, added)
+		end
+
+		for _, updated in ipairs(patch.updated) do
+			output:writeLine("Update ID {} {:#?}", updated.id, updated)
+		end
+
+		output:unindent()
+		output:write("}")
+	end)
+end
+
+local ServeSession = {}
+ServeSession.__index = ServeSession
+
+ServeSession.Status = Status
+
+local validateServeOptions = t.strictInterface({
+	apiContext = t.table,
+})
+
+function ServeSession.new(options)
+	assert(validateServeOptions(options))
+
+	-- Declare self ahead of time to capture it in a closure
+	local self
+	local function onInstanceChanged(instance, propertyName)
+		self:__onInstanceChanged(instance, propertyName)
+	end
+
+	local instanceMap = InstanceMap.new(onInstanceChanged)
+	local reconciler = Reconciler.new(instanceMap)
+
+	self = {
+		__status = Status.NotStarted,
+		__apiContext = options.apiContext,
+		__reconciler = reconciler,
+		__instanceMap = instanceMap,
+		__statusChangedCallback = nil,
+	}
+
+	setmetatable(self, ServeSession)
+
+	return self
+end
+
+function ServeSession:__fmtDebug(output)
+	output:writeLine("ServeSession {{")
+	output:indent()
+
+	output:writeLine("API Context: {:#?}", self.__apiContext)
+	output:writeLine("Instances: {:#?}", self.__instanceMap)
+
+	output:unindent()
+	output:write("}")
+end
+
+function ServeSession:onStatusChanged(callback)
+	self.__statusChangedCallback = callback
+end
+
+function ServeSession:start()
+	self:__setStatus(Status.Connecting)
+
+	self.__apiContext:connect()
+		:andThen(function(serverInfo)
+			self:__setStatus(Status.Connected)
+
+			local rootInstanceId = serverInfo.rootInstanceId
+
+			return self:__initialSync(rootInstanceId)
+				:andThen(function()
+					return self:__mainSyncLoop()
+				end)
+		end)
+		:catch(function(err)
+			self:__stopInternal(err)
+		end)
+end
+
+function ServeSession:stop()
+	self:__stopInternal()
+end
+
+function ServeSession:__onInstanceChanged(instance, propertyName)
+	if not DevSettings:twoWaySyncEnabled() then
+		return
+	end
+
+	local instanceId = self.__instanceMap.fromInstances[instance]
+
+	if instanceId == nil then
+		Log.warn("Ignoring change for instance {:?} as it is unknown to Rojo", instance)
+		return
+	end
+
+	local update = {
+		id = instanceId,
+		changedProperties = {},
+	}
+
+	if propertyName == "Name" then
+		update.changedName = instance.Name
+	else
+		local success, encoded = self.__reconciler:encodeApiValue(instance[propertyName])
+
+		if not success then
+			Log.warn("Could not sync back property {:?}.{}", instance, propertyName)
+			return
+		end
+
+		update.changedProperties[propertyName] = encoded
+	end
+
+	local patch = {
+		removed = {},
+		added = {},
+		updated = {update},
+	}
+
+	self.__apiContext:write(patch)
+end
+
+function ServeSession:__initialSync(rootInstanceId)
+	return self.__apiContext:read({ rootInstanceId })
+		:andThen(function(readResponseBody)
+			-- Tell the API Context that we're up-to-date with the version of
+			-- the tree defined in this response.
+			self.__apiContext:setMessageCursor(readResponseBody.messageCursor)
+
+			Log.trace("Computing changes that plugin needs to make to catch up to server...")
+
+			-- Calculate the initial patch to apply to the DataModel to catch us
+			-- up to what Rojo thinks the place should look like.
+			local hydratePatch = self.__reconciler:hydrate(
+				readResponseBody.instances,
+				rootInstanceId,
+				game
+			)
+
+			Log.trace("Computed hydration patch: {:#?}", debugPatch(hydratePatch))
+
+			-- TODO: Prompt user to notify them of this patch, since it's
+			-- effectively a conflict between the Rojo server and the client.
+
+			self.__reconciler:applyPatch(hydratePatch)
+		end)
+end
+
+function ServeSession:__mainSyncLoop()
+	return self.__apiContext:retrieveMessages()
+		:andThen(function(messages)
+			for _, message in ipairs(messages) do
+				self.__reconciler:applyPatch(message)
+			end
+
+			if self.__status ~= Status.Disconnected then
+				return self:__mainSyncLoop()
+			end
+		end)
+end
+
+function ServeSession:__stopInternal(err)
+	self:__setStatus(Status.Disconnected, err)
+	self.__apiContext:disconnect()
+	self.__instanceMap:stop()
+end
+
+function ServeSession:__setStatus(status, detail)
+	self.__status = status
+
+	if self.__statusChangedCallback ~= nil then
+		self.__statusChangedCallback(status, detail)
+	end
+end
+
+return ServeSession

plugin/src/Session.lua

@@ -1,97 +0,0 @@
-local Rojo = script:FindFirstAncestor("Rojo")
-
-local Promise = require(Rojo.Promise)
-
-local ApiContext = require(script.Parent.ApiContext)
-local Reconciler = require(script.Parent.Reconciler)
-
-local Session = {}
-Session.__index = Session
-
-function Session.new(config)
-	local remoteUrl = ("http://%s:%s"):format(config.address, config.port)
-	local api = ApiContext.new(remoteUrl)
-
-	local self = {
-		onError = config.onError,
-		disconnected = false,
-		reconciler = Reconciler.new(),
-		api = api,
-	}
-
-	api:connect()
-		:andThen(function()
-			if self.disconnected then
-				return
-			end
-
-			return api:read({api.rootInstanceId})
-		end)
-		:andThen(function(response)
-			if self.disconnected then
-				return
-			end
-
-			self.reconciler:reconcile(response.instances, api.rootInstanceId, game)
-			return self:__processMessages(response.messageCursor)
-		end)
-		:catch(function(message)
-			self.disconnected = true
-			self.onError(message)
-		end)
-
-	return not self.disconnected, setmetatable(self, Session)
-end
-
-function Session:__processMessages(initialCursor)
-	if self.disconnected then
-		return Promise.resolve()
-	end
-
-	return self.api:retrieveMessages(initialCursor)
-		:andThen(function(messages)
-			local promise = Promise.resolve(nil)
-
-			for _, message in ipairs(messages) do
-				promise = promise:andThen(function()
-					return self:__onMessage(message)
-				end)
-			end
-
-			return promise
-		end)
-		:andThen(function()
-			return self:__processMessages()
-		end)
-end
-
-function Session:__onMessage(message)
-	if self.disconnected then
-		return Promise.resolve()
-	end
-
-	local requestedIds = {}
-
-	for _, id in ipairs(message.added) do
-		table.insert(requestedIds, id)
-	end
-
-	for _, id in ipairs(message.updated) do
-		table.insert(requestedIds, id)
-	end
-
-	for _, id in ipairs(message.removed) do
-		table.insert(requestedIds, id)
-	end
-
-	return self.api:read(requestedIds)
-		:andThen(function(response)
-			return self.reconciler:applyUpdate(requestedIds, response.instances)
-		end)
-end
-
-function Session:disconnect()
-	self.disconnected = true
-end
-
-return Session

plugin/src/Theme.lua

@@ -1,4 +1,6 @@
-local Theme = {
+local strict = require(script.Parent.strict)
+
+return strict("Theme", {
 	ButtonFont = Enum.Font.GothamSemibold,
 	InputFont = Enum.Font.Code,
 	TitleFont = Enum.Font.GothamBold,
@@ -9,12 +11,4 @@ local Theme = {
 	PrimaryColor = Color3.fromRGB(64, 64, 64),
 	SecondaryColor = Color3.fromRGB(235, 235, 235),
 	LightTextColor = Color3.fromRGB(160, 160, 160),
-}
-
-setmetatable(Theme, {
-	__index = function(_, key)
-		error(("%s is not a valid member of Theme"):format(key), 2)
-	end
-})
-
-return Theme
+})

plugin/src/Types.lua

@@ -1,21 +1,70 @@
 local t = require(script.Parent.Parent.t)
 
 local DevSettings = require(script.Parent.DevSettings)
+local strict = require(script.Parent.strict)
 
-local VirtualValue = t.interface({
+local RbxId = t.string
+
+local ApiValue = t.interface({
 	Type = t.string,
 	Value = t.optional(t.any),
 })
 
-local VirtualMetadata = t.interface({
+local ApiInstanceMetadata = t.interface({
 	ignoreUnknownInstances = t.optional(t.boolean),
 })
 
-local VirtualInstance = t.interface({
+local ApiInstance = t.interface({
+	Id = RbxId,
+	Parent = t.optional(RbxId),
 	Name = t.string,
 	ClassName = t.string,
-	Properties = t.map(t.string, VirtualValue),
-	Metadata = t.optional(VirtualMetadata)
+	Properties = t.map(t.string, ApiValue),
+	Metadata = t.optional(ApiInstanceMetadata),
+	Children = t.array(RbxId),
+})
+
+local ApiInstanceUpdate = t.interface({
+	id = RbxId,
+	changedName = t.optional(t.string),
+	changedClassName = t.optional(t.string),
+	changedProperties = t.map(t.string, ApiValue),
+	changedMetadata = t.optional(ApiInstanceMetadata),
+})
+
+local ApiSubscribeMessage = t.interface({
+	removed = t.array(RbxId),
+	added = t.map(RbxId, ApiInstance),
+	updated = t.array(ApiInstanceUpdate),
+})
+
+local ApiInfoResponse = t.interface({
+	sessionId = t.string,
+	serverVersion = t.string,
+	protocolVersion = t.number,
+	expectedPlaceIds = t.optional(t.array(t.number)),
+	rootInstanceId = RbxId,
+})
+
+local ApiReadResponse = t.interface({
+	sessionId = t.string,
+	messageCursor = t.number,
+	instances = t.map(RbxId, ApiInstance),
+})
+
+local ApiSubscribeResponse = t.interface({
+	sessionId = t.string,
+	messageCursor = t.number,
+	messages = t.array(ApiSubscribeMessage),
+})
+
+local ApiError = t.interface({
+	kind = t.union(
+		t.literal("NotFound"),
+		t.literal("BadRequest"),
+		t.literal("InternalError")
+	),
+	details = t.string,
 })
 
 local function ifEnabled(innerCheck)
@@ -28,9 +77,23 @@ local function ifEnabled(innerCheck)
 	end
 end
 
-return {
+return strict("Types", {
 	ifEnabled = ifEnabled,
-	VirtualInstance = VirtualInstance,
-	VirtualMetadata = VirtualMetadata,
-	VirtualValue = VirtualValue,
-}
+
+	ApiInfoResponse = ApiInfoResponse,
+	ApiReadResponse = ApiReadResponse,
+	ApiSubscribeResponse = ApiSubscribeResponse,
+	ApiError = ApiError,
+
+	ApiInstance = ApiInstance,
+	ApiInstanceUpdate = ApiInstanceUpdate,
+	ApiInstanceMetadata = ApiInstanceMetadata,
+	ApiSubscribeMessage = ApiSubscribeMessage,
+	ApiValue = ApiValue,
+	RbxId = RbxId,
+
+	-- Deprecated aliases during transition
+	VirtualInstance = ApiInstance,
+	VirtualMetadata = ApiInstanceMetadata,
+	VirtualValue = ApiValue,
+})

plugin/src/getCanonicalProperty.lua

@@ -0,0 +1,39 @@
+local RbxDom = require(script.Parent.Parent.RbxDom)
+
+--[[
+	Attempts to set a property on the given instance.
+]]
+local function getCanonincalProperty(instance, propertyName)
+	local descriptor = RbxDom.findCanonicalPropertyDescriptor(instance.ClassName, propertyName)
+
+	-- We can skip unknown properties; they're not likely reflected to Lua.
+	--
+	-- A good example of a property like this is `Model.ModelInPrimary`, which
+	-- is serialized but not reflected to Lua.
+	if descriptor == nil then
+		return false, "unknown property"
+	end
+
+	if descriptor.scriptability == "None" or descriptor.scriptability == "Write" then
+		return false, "unreadable property"
+	end
+
+	local success, valueOrErr = descriptor:read(instance)
+
+	if not success then
+		local err = valueOrErr
+
+		-- If we don't have permission to read a property, we can chalk that up
+		-- to our database being out of date and the engine being right.
+		if err.kind == RbxDom.Error.Kind.Roblox and err.extra:find("lacking permission") then
+			return false, "permission error"
+		end
+
+		local message = ("Invalid property %s.%s: %s"):format(descriptor.className, descriptor.name, tostring(err))
+		error(message, 2)
+	end
+
+	return true, valueOrErr
+end
+
+return getCanonincalProperty

plugin/src/init.server.lua

@@ -2,8 +2,17 @@ if not plugin then
 	return
 end
 
+local Log = require(script.Parent.Log)
+
+local DevSettings = require(script.DevSettings)
+
+Log.setLogLevelThunk(function()
+	return DevSettings:getLogLevel()
+end)
+
 local Roact = require(script.Parent.Roact)
 
+local Config = require(script.Config)
 local App = require(script.Components.App)
 
 local app = Roact.createElement(App, {
@@ -14,4 +23,10 @@ local tree = Roact.mount(app, game:GetService("CoreGui"), "Rojo UI")
 
 plugin.Unloading:Connect(function()
 	Roact.unmount(tree)
-end)
+end)
+
+if Config.isDevBuild then
+	local TestEZ = require(script.Parent.TestEZ)
+
+	require(script.runTests)(TestEZ)
+end

plugin/src/init.spec.lua

@@ -0,0 +1,15 @@
+return function()
+	it("should load all submodules", function()
+		local function loadRecursive(container)
+			if container:IsA("ModuleScript") and not container.Name:find("%.spec$") then
+				require(container)
+			end
+
+			for _, child in ipairs(container:GetChildren()) do
+				loadRecursive(child)
+			end
+		end
+
+		loadRecursive(script.Parent)
+	end)
+end

plugin/src/invariant.lua

@@ -0,0 +1,29 @@
+local Fmt = require(script.Parent.Parent.Fmt)
+
+local Config = require(script.Parent.Config)
+
+local invariant
+
+if Config.isDevBuild then
+	function invariant(message, ...)
+		message = Fmt.fmt(message, ...)
+
+		error("Invariant violation: " .. message, 2)
+	end
+else
+	function invariant(message, ...)
+		message = Fmt.fmt(message, ...)
+
+		local fullMessage = string.format(
+			"Rojo detected an invariant violation within itself:\n" ..
+			"%s\n\n" ..
+			"This is a bug in Rojo. Please file an issue:\n" ..
+			"https://github.com/rojo-rbx/rojo/issues",
+			message
+		)
+
+		error(fullMessage, 2)
+	end
+end
+
+return invariant

plugin/src/preloadAssets.lua

@@ -1,6 +1,7 @@
 local ContentProvider = game:GetService("ContentProvider")
 
-local Logging = require(script.Parent.Logging)
+local Log = require(script.Parent.Parent.Log)
+
 local Assets = require(script.Parent.Assets)
 
 local function preloadAssets()
@@ -18,7 +19,7 @@ local function preloadAssets()
 		table.insert(contentUrls, url)
 	end
 
-	Logging.trace("Preloading assets: %s", table.concat(contentUrls, ", "))
+	Log.trace("Preloading assets: {:?}", contentUrls)
 
 	coroutine.wrap(function()
 		ContentProvider:PreloadAsync(contentUrls)

plugin/src/rojoValueToRobloxValue.lua

@@ -1,19 +0,0 @@
-local RbxDom = require(script:FindFirstAncestor("Rojo").RbxDom)
-
-local function rojoValueToRobloxValue(value)
-	-- TODO: Manually decode this value by looking up its GUID The Rojo server
-	-- doesn't give us valid ref values yet, so this isn't important yet.
-	if value.Type == "Ref" then
-		return nil
-	end
-
-	local success, decodedValue = RbxDom.EncodedValue.decode(value)
-
-	if not success then
-		error(decodedValue, 2)
-	end
-
-	return decodedValue
-end
-
-return rojoValueToRobloxValue

plugin/src/rojoValueToRobloxValue.spec.lua

@@ -1,40 +0,0 @@
-local rojoValueToRobloxValue = require(script.Parent.rojoValueToRobloxValue)
-
-return function()
-	it("should convert primitives", function()
-		local inputString = {
-			Type = "String",
-			Value = "Hello, world!",
-		}
-
-		local inputFloat32 = {
-			Type = "Float32",
-			Value = 12341.512,
-		}
-
-		expect(rojoValueToRobloxValue(inputString)).to.equal(inputString.Value)
-		expect(rojoValueToRobloxValue(inputFloat32)).to.equal(inputFloat32.Value)
-	end)
-
-	it("should convert properties with direct constructors", function()
-		local inputColor3 = {
-			Type = "Color3",
-			Value = {0, 1, 0.5},
-		}
-		local outputColor3 = Color3.new(0, 1, 0.5)
-
-		local inputCFrame = {
-			Type = "CFrame",
-			Value = {
-				1, 2, 3,
-				4, 5, 6,
-				7, 8, 9,
-				10, 11, 12,
-			},
-		}
-		local outputCFrame = CFrame.new(1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-		expect(rojoValueToRobloxValue(inputColor3)).to.equal(outputColor3)
-		expect(rojoValueToRobloxValue(inputCFrame)).to.equal(outputCFrame)
-	end)
-end

plugin/src/runTests.lua

@@ -1,4 +1,5 @@
-return function()
-	local TestEZ = require(script.Parent.Parent.TestEZ)
-	TestEZ.TestBootstrap:run(script.Parent)
-end
+return function(TestEZ)
+	local Rojo = script.Parent.Parent
+
+	TestEZ.TestBootstrap:run({ Rojo.Plugin, Rojo.Http, Rojo.Log })
+end

plugin/src/setCanonicalProperty.lua

@@ -1,4 +1,4 @@
-local RbxDom = require(script:FindFirstAncestor("Rojo").RbxDom)
+local RbxDom = require(script.Parent.Parent.RbxDom)
 
 --[[
 	Attempts to set a property on the given instance.

plugin/src/strict.lua

@@ -0,0 +1,24 @@
+local function strictInner(name, target)
+	assert(type(name) == "string", "Argument #1 to `strict` must be a string or the table to modify")
+	assert(type(target) == "table", "Argument #2 to `strict` must be nil or the table to modify")
+
+	setmetatable(target, {
+		__index = function(_, key)
+			error(("%q is not a valid member of strict table %q"):format(tostring(key), name), 2)
+		end,
+
+		__newindex = function()
+			error(("Strict table %q is read-only"):format(name), 2)
+		end,
+	})
+
+	return target
+end
+
+return function(nameOrTarget, target)
+	if type(nameOrTarget) == "string" then
+		return strictInner(nameOrTarget, target)
+	else
+		return strictInner("<unnamed table>", target)
+	end
+end

plugin/testBootstrap.server.lua

@@ -12,7 +12,7 @@ if setDevSettings then
 	DevSettings:createTestSettings()
 end
 
-TestEZ.TestBootstrap:run({Rojo.Plugin})
+require(Rojo.Plugin.runTests)(TestEZ)
 
 if setDevSettings then
 	DevSettings:resetValues()

plugin/testez.project.json

@@ -0,0 +1,6 @@
+{
+  "name": "TestEZ",
+  "tree": {
+    "$path": "modules/testez/lib"
+  }
+}

plugin/tests/empty.lua

@@ -1,5 +0,0 @@
-local ReplicatedStorage = game:GetService("ReplicatedStorage")
-
-local Session = require(ReplicatedStorage.Modules.Rojo.Session)
-
-Session.new()

rojo-insta-ext/Cargo.toml

@@ -0,0 +1,10 @@
+[package]
+name = "rojo-insta-ext"
+version = "0.1.0"
+authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+edition = "2018"
+publish = false
+
+[dependencies]
+serde = "1.0.99"
+serde_yaml = "0.8.9"

rojo-insta-ext/README.md

@@ -0,0 +1,2 @@
+# Rojo Insta Extensions
+This crate has add-ons intended for use with Insta that are useful for snapshot tests.

rojo-insta-ext/src/lib.rs

@@ -0,0 +1,3 @@
+mod redaction_map;
+
+pub use redaction_map::*;

rojo-insta-ext/src/redaction_map.rs

@@ -0,0 +1,85 @@
+use std::collections::HashMap;
+
+use serde::Serialize;
+
+/// Enables redacting any value that serializes as a string.
+///
+/// Used for transforming Rojo instance IDs into something deterministic.
+pub struct RedactionMap {
+    ids: HashMap<String, usize>,
+    last_id: usize,
+}
+
+impl RedactionMap {
+    pub fn new() -> Self {
+        Self {
+            ids: HashMap::new(),
+            last_id: 0,
+        }
+    }
+
+    pub fn get_redacted_value(&self, id: impl ToString) -> Option<String> {
+        let id = id.to_string();
+
+        if self.ids.contains_key(&id) {
+            Some(id)
+        } else {
+            None
+        }
+    }
+
+    pub fn intern(&mut self, id: impl ToString) {
+        let last_id = &mut self.last_id;
+
+        self.ids.entry(id.to_string()).or_insert_with(|| {
+            *last_id += 1;
+            *last_id
+        });
+    }
+
+    pub fn intern_iter<S: ToString>(&mut self, ids: impl Iterator<Item = S>) {
+        for id in ids {
+            self.intern(id.to_string());
+        }
+    }
+
+    pub fn redacted_yaml(&self, value: impl Serialize) -> serde_yaml::Value {
+        let mut encoded = serde_yaml::to_value(value).expect("Couldn't encode value as YAML");
+
+        self.redact(&mut encoded);
+        encoded
+    }
+
+    pub fn redact(&self, yaml_value: &mut serde_yaml::Value) {
+        use serde_yaml::{Mapping, Value};
+
+        match yaml_value {
+            Value::String(value) => {
+                if let Some(redacted) = self.ids.get(value) {
+                    *yaml_value = Value::String(format!("id-{}", *redacted));
+                }
+            }
+            Value::Sequence(sequence) => {
+                for value in sequence {
+                    self.redact(value);
+                }
+            }
+            Value::Mapping(mapping) => {
+                // We can't mutate the keys of a map in-place, so we take
+                // ownership of the map and rebuild it.
+
+                let owned_map = std::mem::replace(mapping, Mapping::new());
+                let mut new_map = Mapping::with_capacity(owned_map.len());
+
+                for (mut key, mut value) in owned_map {
+                    self.redact(&mut key);
+                    self.redact(&mut value);
+                    new_map.insert(key, value);
+                }
+
+                *mapping = new_map;
+            }
+            _ => {}
+        }
+    }
+}

rojo-test/Cargo.toml

@@ -5,10 +5,28 @@ authors = ["Lucien Greathouse <me@lpghatguy.com>"]
 edition = "2018"
 publish = false
 
+[features]
+default = []
+
+unstable_glob_ignore_paths = []
+
 [dependencies]
-insta = "0.10.0"
+env_logger = "0.6.2"
+log = "0.4.8"
 paste = "0.1.5"
+rbx_dom_weak = "1.9.0"
+reqwest = "0.9.20"
+serde = "1.0.99"
+serde_json = "1.0.40"
+serde_yaml = "0.8.9"
 tempfile = "3.1.0"
+walkdir = "2.2.9"
+
+rojo-insta-ext = { path = "../rojo-insta-ext" }
 
 # We execute Rojo via std::process::Command, so depend on it so it's built!
-rojo = { path = "../server" }
+rojo = { path = ".." }
+
+[dependencies.insta]
+git = "https://github.com/mitsuhiko/insta"
+features = ["redactions"]

rojo-test/README.md

@@ -0,0 +1,8 @@
+# rojo-test
+This project does end-to-end testing of Rojo by executing it and checking what side-effects it has.
+
+rojo-test is meant to be run as a test with:
+
+```bash
+cargo test
+```

rojo-test/build-test-snapshots/build_test__client_in_folder.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-09T01:29:47.650277200Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---

rojo-test/build-test-snapshots/build_test__client_init.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-16T19:37:51.277332900Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---

rojo-test/build-test-snapshots/build_test__csv_bug_145.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-14T22:42:52.297447700Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---
@@ -16,4 +14,4 @@ expression: contents
       </Properties>
     </Item>
   </Item>
-</roblox>
+</roblox>

rojo-test/build-test-snapshots/build_test__csv_bug_147.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-14T22:42:52.310414Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---
@@ -16,4 +14,4 @@ expression: contents
       </Properties>
     </Item>
   </Item>
-</roblox>
+</roblox>

rojo-test/build-test-snapshots/build_test__csv_in_folder.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-14T22:34:06.206495600Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---

rojo-test/build-test-snapshots/build_test__deep_nesting.snap

@@ -0,0 +1,26 @@
+---
+source: rojo-test/src/build_test.rs
+expression: contents
+---
+<roblox version="4">
+  <Item class="Folder" referent="0">
+    <Properties>
+      <string name="Name">deep_nesting</string>
+    </Properties>
+    <Item class="Folder" referent="1">
+      <Properties>
+        <string name="Name">level-1</string>
+      </Properties>
+      <Item class="Folder" referent="2">
+        <Properties>
+          <string name="Name">level-2</string>
+        </Properties>
+        <Item class="Folder" referent="3">
+          <Properties>
+            <string name="Name">level-3</string>
+          </Properties>
+        </Item>
+      </Item>
+    </Item>
+  </Item>
+</roblox>

rojo-test/build-test-snapshots/build_test__gitkeep.snap

@@ -1,6 +1,4 @@
 ---
-created: "2019-08-08T00:48:33.382271800Z"
-creator: insta@0.10.0
 source: rojo-test/src/build_test.rs
 expression: contents
 ---

rojo-test/build-test-snapshots/build_test__ignore_glob_inner.snap

@@ -0,0 +1,33 @@
+---
+source: rojo-test/src/build_test.rs
+expression: contents
+---
+<roblox version="4">
+  <Item class="Folder" referent="0">
+    <Properties>
+      <string name="Name">ignore_glob_inner</string>
+    </Properties>
+    <Item class="Folder" referent="1">
+      <Properties>
+        <string name="Name">src</string>
+      </Properties>
+      <Item class="ModuleScript" referent="2">
+        <Properties>
+          <string name="Name">outer.spec</string>
+          <string name="Source">-- This file should be included.</string>
+        </Properties>
+      </Item>
+    </Item>
+    <Item class="Folder" referent="3">
+      <Properties>
+        <string name="Name">subproject</string>
+      </Properties>
+      <Item class="ModuleScript" referent="4">
+        <Properties>
+          <string name="Name">inner</string>
+          <string name="Source">-- This file should be included.</string>
+        </Properties>
+      </Item>
+    </Item>
+  </Item>
+</roblox>

rojo-test/build-test-snapshots/build_test__ignore_glob_nested.snap

@@ -0,0 +1,17 @@
+---
+source: rojo-test/src/build_test.rs
+expression: contents
+---
+<roblox version="4">
+  <Item class="Folder" referent="0">
+    <Properties>
+      <string name="Name">ignore_glob_nested</string>
+    </Properties>
+    <Item class="ModuleScript" referent="1">
+      <Properties>
+        <string name="Name">include</string>
+        <string name="Source">-- This file must be present.</string>
+      </Properties>
+    </Item>
+  </Item>
+</roblox>

rojo-test/build-test-snapshots/build_test__ignore_glob_spec.snap

@@ -0,0 +1,17 @@
+---
+source: rojo-test/src/build_test.rs
+expression: contents
+---
+<roblox version="4">
+  <Item class="Folder" referent="0">
+    <Properties>
+      <string name="Name">ignore_glob_spec</string>
+    </Properties>
+    <Item class="ModuleScript" referent="1">
+      <Properties>
+        <string name="Name">shouldBeIncluded</string>
+        <string name="Source">-- this file should be present</string>
+      </Properties>
+    </Item>
+  </Item>
+</roblox>