feat: resolve duplicate sibling names with incrementing suffixes

Instead of bailing when children have duplicate filesystem names,
syncback now resolves collisions by appending incrementing suffixes
(e.g. Foo, Foo1, Foo2). This handles both init-renamed children and
any other name collisions. Meta stem derivation is now path-based
to correctly handle collision suffixes and dotted names.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.github/workflows/ci.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest]
+        os: [ubuntu-22.04, windows-latest, macos-latest, windows-11-arm, ubuntu-22.04-arm]
 
     steps:
     - uses: actions/checkout@v4
@@ -26,13 +26,14 @@ jobs:
     - name: Install Rust
       uses: dtolnay/rust-toolchain@stable
 
-    - name: Rust cache
+    - name: Restore Rust Cache
-      uses: Swatinem/rust-cache@v2
+      uses: actions/cache/restore@v4
-
-    - name: Setup Aftman
-      uses: ok-nick/setup-aftman@v0.4.2
       with:
-        version: 'v0.3.0'
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ matrix.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
     - name: Build
       run: cargo build --locked --verbose
@@ -40,6 +41,15 @@ jobs:
     - name: Test
       run: cargo test --locked --verbose
 
+    - name: Save Rust Cache
+      uses: actions/cache/save@v4
+      with:
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ matrix.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+
   msrv:
     name: Check MSRV
     runs-on: ubuntu-latest
@@ -50,19 +60,29 @@ jobs:
         submodules: true
 
     - name: Install Rust
-      uses: dtolnay/rust-toolchain@1.70.0
+      uses: dtolnay/rust-toolchain@1.88.0
 
-    - name: Rust cache
+    - name: Restore Rust Cache
-      uses: Swatinem/rust-cache@v2
+      uses: actions/cache/restore@v4
-
-    - name: Setup Aftman
-      uses: ok-nick/setup-aftman@v0.4.2
       with:
-        version: 'v0.3.0'
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
     - name: Build
       run: cargo build --locked --verbose
 
+    - name: Save Rust Cache
+      uses: actions/cache/save@v4
+      with:
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+
   lint:
     name: Rustfmt, Clippy, Stylua, & Selene
     runs-on: ubuntu-latest
@@ -77,13 +97,19 @@ jobs:
       with:
         components: rustfmt, clippy
 
-    - name: Rust cache
+    - name: Restore Rust Cache
-      uses: Swatinem/rust-cache@v2
+      uses: actions/cache/restore@v4
-
-    - name: Setup Aftman
-      uses: ok-nick/setup-aftman@v0.4.2
       with:
-        version: 'v0.3.0'
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
+
+    - name: Setup Rokit
+      uses: CompeyDev/setup-rokit@v0.1.2
+      with:
+        version: 'v1.1.0'
 
     - name: Stylua
       run: stylua --check plugin/src
@@ -97,3 +123,11 @@ jobs:
     - name: Clippy
       run: cargo clippy
 
+    - name: Save Rust Cache
+      uses: actions/cache/save@v4
+      with:
+        path: |
+          ~/.cargo/registry
+          ~/.cargo/git
+          target
+        key: ${{ runner.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}

.github/workflows/release.yml

@@ -25,10 +25,10 @@ jobs:
         with:
           submodules: true
 
-      - name: Setup Aftman
+      - name: Setup Rokit
-        uses: ok-nick/setup-aftman@v0.4.2
+        uses: CompeyDev/setup-rokit@v0.1.2
         with:
-          version: 'v0.3.0'
+          version: 'v1.1.0'
 
       - name: Build Plugin
         run: rojo build plugin.project.json --output Rojo.rbxm
@@ -53,15 +53,25 @@ jobs:
         # https://doc.rust-lang.org/rustc/platform-support.html
         include:
           - host: linux
-            os: ubuntu-latest
+            os: ubuntu-22.04
             target: x86_64-unknown-linux-gnu
             label: linux-x86_64
 
+          - host: linux
+            os: ubuntu-22.04-arm
+            target: aarch64-unknown-linux-gnu
+            label: linux-aarch64
+
           - host: windows
             os: windows-latest
             target: x86_64-pc-windows-msvc
             label: windows-x86_64
 
+          - host: windows
+            os: windows-11-arm
+            target: aarch64-pc-windows-msvc
+            label: windows-aarch64
+
           - host: macos
             os: macos-latest
             target: x86_64-apple-darwin
@@ -86,17 +96,26 @@ jobs:
         with:
           targets: ${{ matrix.target }}
 
-      - name: Setup Aftman
+      - name: Restore Rust Cache
-        uses: ok-nick/setup-aftman@v0.4.2
+        uses: actions/cache/restore@v4
         with:
-          version: 'v0.3.0'
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: ${{ matrix.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Build Release
         run: cargo build --release --locked --verbose --target ${{ matrix.target }}
-        env:
+
-          # Build into a known directory so we can find our build artifact more
+      - name: Save Rust Cache
-          # easily.
+        uses: actions/cache/save@v4
-          CARGO_TARGET_DIR: output
+        with:
+          path: |
+            ~/.cargo/registry
+            ~/.cargo/git
+            target
+          key: ${{ matrix.os }}-cargo-${{ hashFiles('**/Cargo.lock') }}
 
       - name: Generate Artifact Name
         shell: bash
@@ -113,11 +132,11 @@ jobs:
           mkdir staging
 
           if [ "${{ matrix.host }}" = "windows" ]; then
-            cp "output/${{ matrix.target }}/release/$BIN.exe" staging/
+            cp "target/${{ matrix.target }}/release/$BIN.exe" staging/
             cd staging
             7z a ../$ARTIFACT_NAME *
           else
-            cp "output/${{ matrix.target }}/release/$BIN" staging/
+            cp "target/${{ matrix.target }}/release/$BIN" staging/
             cd staging
             zip ../$ARTIFACT_NAME *
           fi

.gitignore

@@ -23,3 +23,6 @@
 # Macos file system junk
 ._*
 .DS_STORE
+
+# JetBrains IDEs
+/.idea/

CONTRIBUTING.md

@@ -15,7 +15,7 @@ You'll want these tools to work on Rojo:
 
 * Latest stable Rust compiler
 * Latest stable [Rojo](https://github.com/rojo-rbx/rojo)
-* [Foreman](https://github.com/Roblox/foreman)
+* [Rokit](https://github.com/rojo-rbx/rokit)
 * [Luau Language Server](https://github.com/JohnnyMorganz/luau-lsp) (Only needed if working on the Studio plugin.)
 
 When working on the Studio plugin, we recommend using this command to automatically rebuild the plugin when you save a change:
@@ -37,7 +37,7 @@ bash scripts/unit-test-plugin.sh
 ## Documentation
 Documentation impacts way more people than the individual lines of code we write.
 
-If you find any problems in documentation, including typos, bad grammar, misleading phrasing, or missing content, feel free to file issues and pull requests to fix them.
+If you find any problems in the documentation, including typos, bad grammar, misleading phrasing, or missing content, feel free to file issues and pull requests to fix them.
 
 ## Bug Reports and Feature Requests
 Most of the tools around Rojo try to be clear when an issue is a bug. Even if they aren't, sometimes things don't work quite right.

Cargo.toml

@@ -1,8 +1,12 @@
 [package]
 name = "rojo"
-version = "7.5.1"
+version = "7.7.0-rc.1"
-rust-version = "1.70.0"
+rust-version = "1.88"
-authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+authors = [
+    "Lucien Greathouse <me@lpghatguy.com>",
+    "Micah Reid <git@dekkonot.com>",
+    "Ken Loeffler <kenloef@gmail.com>",
+]
 description = "Enables professional-grade development tools for Roblox developers"
 license = "MPL-2.0"
 homepage = "https://rojo.space"
@@ -42,20 +46,22 @@ name = "build"
 harness = false
 
 [dependencies]
-memofs = { version = "0.3.0", path = "crates/memofs" }
+memofs = { version = "0.3.1", path = "crates/memofs" }
 
 # These dependencies can be uncommented when working on rbx-dom simultaneously
-# rbx_binary = { path = "../rbx-dom/rbx_binary" }
+# rbx_binary = { path = "../rbx-dom/rbx_binary", features = [
+#     "unstable_text_format",
+# ] }
 # rbx_dom_weak = { path = "../rbx-dom/rbx_dom_weak" }
 # rbx_reflection = { path = "../rbx-dom/rbx_reflection" }
 # rbx_reflection_database = { path = "../rbx-dom/rbx_reflection_database" }
 # rbx_xml = { path = "../rbx-dom/rbx_xml" }
 
-rbx_binary = "1.0.0"
+rbx_binary = { version = "2.0.1", features = ["unstable_text_format"] }
-rbx_dom_weak = "3.0.0"
+rbx_dom_weak = "4.1.0"
-rbx_reflection = "5.0.0"
+rbx_reflection = "6.1.0"
-rbx_reflection_database = "1.0.3"
+rbx_reflection_database = "2.0.2"
-rbx_xml = "1.0.0"
+rbx_xml = "2.0.1"
 
 anyhow = "1.0.80"
 backtrace = "0.3.69"
@@ -68,6 +74,7 @@ futures = "0.3.30"
 globset = "0.4.14"
 humantime = "2.1.0"
 hyper = { version = "0.14.28", features = ["server", "tcp", "http1"] }
+hyper-tungstenite = "0.11.0"
 jod-thread = "0.1.2"
 log = "0.4.21"
 num_cpus = "1.16.0"
@@ -81,14 +88,22 @@ reqwest = { version = "0.11.24", default-features = false, features = [
 ritz = "0.1.0"
 roblox_install = "1.0.0"
 serde = { version = "1.0.197", features = ["derive", "rc"] }
-serde_json = "1.0.114"
+serde_json = "1.0.145"
+jsonc-parser = { version = "0.27.0", features = ["serde"] }
+strum = { version = "0.27", features = ["derive"] }
 toml = "0.5.11"
 termcolor = "1.4.1"
 thiserror = "1.0.57"
-tokio = { version = "1.36.0", features = ["rt", "rt-multi-thread"] }
+tokio = { version = "1.36.0", features = ["rt", "rt-multi-thread", "macros"] }
 uuid = { version = "1.7.0", features = ["v4", "serde"] }
 clap = { version = "3.2.25", features = ["derive"] }
 profiling = "1.0.15"
+yaml-rust2 = "0.10.3"
+data-encoding = "2.8.0"
+
+blake3 = "1.5.0"
+float-cmp = "0.9.0"
+indexmap = { version = "2.10.0", features = ["serde"] }
 
 [target.'cfg(windows)'.dependencies]
 winreg = "0.10.1"

README.md

@@ -40,7 +40,7 @@ Check out our [contribution guide](CONTRIBUTING.md) for detailed instructions fo
 
 Pull requests are welcome!
 
-Rojo supports Rust 1.70.0 and newer. The minimum supported version of Rust is based on the latest versions of the dependencies that Rojo has.
+Rojo supports Rust 1.88 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.

aftman.toml

@@ -1,5 +0,0 @@
-[tools]
-rojo = "rojo-rbx/rojo@7.4.1"
-selene = "Kampfkarren/selene@0.27.1"
-stylua = "JohnnyMorganz/stylua@0.20.0"
-run-in-roblox = "rojo-rbx/run-in-roblox@0.3.0"

assets/index.css

@@ -17,6 +17,10 @@ html {
   line-height: 1.4;
 }
 
+body {
+  background-color: #e7e7e7
+}
+
 img {
   max-width:100%;
   max-height:100%;

assets/project-templates/model/gitignore.txt

@@ -1,3 +1,5 @@
 # Roblox Studio lock files
 /*.rbxlx.lock
-/*.rbxl.lock
+/*.rbxl.lock
+
+sourcemap.json

assets/project-templates/model/src/init.luau

@@ -2,4 +2,4 @@ return {
 	hello = function()
 		print("Hello world, from {project_name}!")
 	end,
-}
+}

assets/project-templates/place/gitignore.txt

@@ -3,4 +3,6 @@
 
 # Roblox Studio lock files
 /*.rbxlx.lock
-/*.rbxl.lock
+/*.rbxl.lock
+
+sourcemap.json

assets/project-templates/place/src/client/init.client.luau

@@ -0,0 +1 @@
+print("Hello world, from client!")

assets/project-templates/place/src/server/init.server.luau

@@ -0,0 +1 @@
+print("Hello world, from server!")

assets/project-templates/place/src/shared/Hello.luau

@@ -0,0 +1,3 @@
+return function()
+	print("Hello, world!")
+end

assets/project-templates/plugin/gitignore.txt

@@ -1,3 +1,5 @@
 # Plugin model files
 /{project_name}.rbxmx
 /{project_name}.rbxm
+
+sourcemap.json

assets/project-templates/plugin/src/init.server.luau

@@ -0,0 +1 @@
+print("Hello world, from plugin!")

build.rs

@@ -47,6 +47,7 @@ fn main() -> Result<(), anyhow::Error> {
 
     let root_dir = PathBuf::from(env::var_os("CARGO_MANIFEST_DIR").unwrap());
     let plugin_dir = root_dir.join("plugin");
+    let templates_dir = root_dir.join("assets").join("project-templates");
 
     let our_version = Version::parse(env::var_os("CARGO_PKG_VERSION").unwrap().to_str().unwrap())?;
     let plugin_version =
@@ -57,7 +58,9 @@ fn main() -> Result<(), anyhow::Error> {
         "plugin version does not match Cargo version"
     );
 
-    let snapshot = VfsSnapshot::dir(hashmap! {
+    let template_snapshot = snapshot_from_fs_path(&templates_dir)?;
+
+    let plugin_snapshot = VfsSnapshot::dir(hashmap! {
         "default.project.json" => snapshot_from_fs_path(&root_dir.join("plugin.project.json"))?,
         "plugin" => VfsSnapshot::dir(hashmap! {
             "fmt" => snapshot_from_fs_path(&plugin_dir.join("fmt"))?,
@@ -70,10 +73,11 @@ fn main() -> Result<(), anyhow::Error> {
         }),
     });
 
-    let out_path = Path::new(&out_dir).join("plugin.bincode");
+    let template_file = File::create(Path::new(&out_dir).join("templates.bincode"))?;
-    let out_file = File::create(out_path)?;
+    let plugin_file = File::create(Path::new(&out_dir).join("plugin.bincode"))?;
 
-    bincode::serialize_into(out_file, &snapshot)?;
+    bincode::serialize_into(plugin_file, &plugin_snapshot)?;
+    bincode::serialize_into(template_file, &template_snapshot)?;
 
     println!("cargo:rerun-if-changed=build/windows/rojo-manifest.rc");
     println!("cargo:rerun-if-changed=build/windows/rojo.manifest");

crates/memofs/CHANGELOG.md

@@ -1,6 +1,14 @@
 # memofs Changelog
 
 ## Unreleased Changes
+* Added `Vfs::canonicalize`. [#1201]
+
+## 0.3.1 (2025-11-27)
+* Added `Vfs::exists`. [#1169]
+* Added `create_dir` and `create_dir_all` to allow creating directories. [#937]
+
+[#1169]: https://github.com/rojo-rbx/rojo/pull/1169
+[#937]: https://github.com/rojo-rbx/rojo/pull/937
 
 ## 0.3.0 (2024-03-15)
 * Changed `StdBackend` file watching component to use minimal recursive watches. [#830]

crates/memofs/Cargo.toml

@@ -1,8 +1,12 @@
 [package]
 name = "memofs"
 description = "Virtual filesystem with configurable backends."
-version = "0.3.0"
+version = "0.3.1"
-authors = ["Lucien Greathouse <me@lpghatguy.com>"]
+authors = [
+    "Lucien Greathouse <me@lpghatguy.com>",
+    "Micah Reid <git@dekkonot.com>",
+    "Ken Loeffler <kenloef@gmail.com>",
+]
 edition = "2018"
 readme = "README.md"
 license = "MIT"
@@ -15,3 +19,6 @@ crossbeam-channel = "0.5.12"
 fs-err = "2.11.0"
 notify = "4.0.17"
 serde = { version = "1.0.197", features = ["derive"] }
+
+[dev-dependencies]
+tempfile = "3.10.1"

crates/memofs/src/in_memory_fs.rs

@@ -157,6 +157,11 @@ impl VfsBackend for InMemoryFs {
         )
     }
 
+    fn exists(&mut self, path: &Path) -> io::Result<bool> {
+        let inner = self.inner.lock().unwrap();
+        Ok(inner.entries.contains_key(path))
+    }
+
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
         let inner = self.inner.lock().unwrap();
 
@@ -176,6 +181,21 @@ impl VfsBackend for InMemoryFs {
         }
     }
 
+    fn create_dir(&mut self, path: &Path) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+        inner.load_snapshot(path.to_path_buf(), VfsSnapshot::empty_dir())
+    }
+
+    fn create_dir_all(&mut self, path: &Path) -> io::Result<()> {
+        let mut inner = self.inner.lock().unwrap();
+        let mut path_buf = path.to_path_buf();
+        while let Some(parent) = path_buf.parent() {
+            inner.load_snapshot(parent.to_path_buf(), VfsSnapshot::empty_dir())?;
+            path_buf.pop();
+        }
+        inner.load_snapshot(path.to_path_buf(), VfsSnapshot::empty_dir())
+    }
+
     fn remove_file(&mut self, path: &Path) -> io::Result<()> {
         let mut inner = self.inner.lock().unwrap();
 
@@ -212,6 +232,33 @@ impl VfsBackend for InMemoryFs {
         }
     }
 
+    // TODO: We rely on Rojo to prepend cwd to any relative path before storing paths
+    // in MemoFS. The current implementation will error if no prepended absolute path
+    // is found. It really only normalizes paths within the provided path's context.
+    // Example: "/Users/username/project/../other/file.txt" ->
+    // "/Users/username/other/file.txt"
+    // Erroneous example: "/Users/../../other/file.txt" -> "/other/file.txt"
+    // This is not very robust. We should implement proper path normalization here or otherwise
+    // warn if we are missing context and can not fully canonicalize the path correctly.
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf> {
+        let mut normalized = PathBuf::new();
+        for component in path.components() {
+            match component {
+                std::path::Component::ParentDir => {
+                    normalized.pop();
+                }
+                std::path::Component::CurDir => {}
+                _ => normalized.push(component),
+            }
+        }
+
+        let inner = self.inner.lock().unwrap();
+        match inner.entries.get(&normalized) {
+            Some(_) => Ok(normalized),
+            None => not_found(&normalized),
+        }
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         let inner = self.inner.lock().unwrap();
 
@@ -228,23 +275,17 @@ impl VfsBackend for InMemoryFs {
 }
 
 fn must_be_file<T>(path: &Path) -> io::Result<T> {
-    Err(io::Error::new(
+    Err(io::Error::other(format!(
-        io::ErrorKind::Other,
+        "path {} was a directory, but must be a file",
-        format!(
+        path.display()
-            "path {} was a directory, but must be a file",
+    )))
-            path.display()
-        ),
-    ))
 }
 
 fn must_be_dir<T>(path: &Path) -> io::Result<T> {
-    Err(io::Error::new(
+    Err(io::Error::other(format!(
-        io::ErrorKind::Other,
+        "path {} was a file, but must be a directory",
-        format!(
+        path.display()
-            "path {} was a file, but must be a directory",
+    )))
-            path.display()
-        ),
-    ))
 }
 
 fn not_found<T>(path: &Path) -> io::Result<T> {

crates/memofs/src/lib.rs

@@ -70,10 +70,14 @@ impl<T> IoResultExt<T> for io::Result<T> {
 pub trait VfsBackend: sealed::Sealed + Send + 'static {
     fn read(&mut self, path: &Path) -> io::Result<Vec<u8>>;
     fn write(&mut self, path: &Path, data: &[u8]) -> io::Result<()>;
+    fn exists(&mut self, path: &Path) -> io::Result<bool>;
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir>;
+    fn create_dir(&mut self, path: &Path) -> io::Result<()>;
+    fn create_dir_all(&mut self, path: &Path) -> io::Result<()>;
     fn metadata(&mut self, path: &Path) -> io::Result<Metadata>;
     fn remove_file(&mut self, path: &Path) -> io::Result<()>;
     fn remove_dir_all(&mut self, path: &Path) -> io::Result<()>;
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf>;
 
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent>;
     fn watch(&mut self, path: &Path) -> io::Result<()>;
@@ -173,6 +177,11 @@ impl VfsInner {
         Ok(Arc::new(contents_str.into()))
     }
 
+    fn exists<P: AsRef<Path>>(&mut self, path: P) -> io::Result<bool> {
+        let path = path.as_ref();
+        self.backend.exists(path)
+    }
+
     fn write<P: AsRef<Path>, C: AsRef<[u8]>>(&mut self, path: P, contents: C) -> io::Result<()> {
         let path = path.as_ref();
         let contents = contents.as_ref();
@@ -190,6 +199,16 @@ impl VfsInner {
         Ok(dir)
     }
 
+    fn create_dir<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.backend.create_dir(path)
+    }
+
+    fn create_dir_all<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.backend.create_dir_all(path)
+    }
+
     fn remove_file<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
         let path = path.as_ref();
         let _ = self.backend.unwatch(path);
@@ -207,6 +226,11 @@ impl VfsInner {
         self.backend.metadata(path)
     }
 
+    fn canonicalize<P: AsRef<Path>>(&mut self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.backend.canonicalize(path)
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         self.backend.event_receiver()
     }
@@ -326,6 +350,42 @@ impl Vfs {
         self.inner.lock().unwrap().read_dir(path)
     }
 
+    /// Return whether the given path exists.
+    ///
+    /// Roughly equivalent to [`std::fs::exists`][std::fs::exists].
+    ///
+    /// [std::fs::exists]: https://doc.rust-lang.org/stable/std/fs/fn.exists.html
+    #[inline]
+    pub fn exists<P: AsRef<Path>>(&self, path: P) -> io::Result<bool> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().exists(path)
+    }
+
+    /// Creates a directory at the provided location.
+    ///
+    /// Roughly equivalent to [`std::fs::create_dir`][std::fs::create_dir].
+    /// Similiar to that function, this function will fail if the parent of the
+    /// path does not exist.
+    ///
+    /// [std::fs::create_dir]: https://doc.rust-lang.org/stable/std/fs/fn.create_dir.html
+    #[inline]
+    pub fn create_dir<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().create_dir(path)
+    }
+
+    /// Creates a directory at the provided location, recursively creating
+    /// all parent components if they are missing.
+    ///
+    /// Roughly equivalent to [`std::fs::create_dir_all`][std::fs::create_dir_all].
+    ///
+    /// [std::fs::create_dir_all]: https://doc.rust-lang.org/stable/std/fs/fn.create_dir_all.html
+    #[inline]
+    pub fn create_dir_all<P: AsRef<Path>>(&self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().create_dir_all(path)
+    }
+
     /// Remove a file.
     ///
     /// Roughly equivalent to [`std::fs::remove_file`][std::fs::remove_file].
@@ -359,6 +419,19 @@ impl Vfs {
         self.inner.lock().unwrap().metadata(path)
     }
 
+    /// Normalize a path via the underlying backend.
+    ///
+    /// Roughly equivalent to [`std::fs::canonicalize`][std::fs::canonicalize]. Relative paths are
+    /// resolved against the backend's current working directory (if applicable) and errors are
+    /// surfaced directly from the backend.
+    ///
+    /// [std::fs::canonicalize]: https://doc.rust-lang.org/stable/std/fs/fn.canonicalize.html
+    #[inline]
+    pub fn canonicalize<P: AsRef<Path>>(&self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.inner.lock().unwrap().canonicalize(path)
+    }
+
     /// Retrieve a handle to the event receiver for this `Vfs`.
     #[inline]
     pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
@@ -428,6 +501,31 @@ impl VfsLock<'_> {
         self.inner.read_dir(path)
     }
 
+    /// Creates a directory at the provided location.
+    ///
+    /// Roughly equivalent to [`std::fs::create_dir`][std::fs::create_dir].
+    /// Similiar to that function, this function will fail if the parent of the
+    /// path does not exist.
+    ///
+    /// [std::fs::create_dir]: https://doc.rust-lang.org/stable/std/fs/fn.create_dir.html
+    #[inline]
+    pub fn create_dir<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.create_dir(path)
+    }
+
+    /// Creates a directory at the provided location, recursively creating
+    /// all parent components if they are missing.
+    ///
+    /// Roughly equivalent to [`std::fs::create_dir_all`][std::fs::create_dir_all].
+    ///
+    /// [std::fs::create_dir_all]: https://doc.rust-lang.org/stable/std/fs/fn.create_dir_all.html
+    #[inline]
+    pub fn create_dir_all<P: AsRef<Path>>(&mut self, path: P) -> io::Result<()> {
+        let path = path.as_ref();
+        self.inner.create_dir_all(path)
+    }
+
     /// Remove a file.
     ///
     /// Roughly equivalent to [`std::fs::remove_file`][std::fs::remove_file].
@@ -461,6 +559,13 @@ impl VfsLock<'_> {
         self.inner.metadata(path)
     }
 
+    /// Normalize a path via the underlying backend.
+    #[inline]
+    pub fn normalize<P: AsRef<Path>>(&mut self, path: P) -> io::Result<PathBuf> {
+        let path = path.as_ref();
+        self.inner.canonicalize(path)
+    }
+
     /// Retrieve a handle to the event receiver for this `Vfs`.
     #[inline]
     pub fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
@@ -476,7 +581,9 @@ impl VfsLock<'_> {
 
 #[cfg(test)]
 mod test {
-    use crate::{InMemoryFs, Vfs, VfsSnapshot};
+    use crate::{InMemoryFs, StdBackend, Vfs, VfsSnapshot};
+    use std::io;
+    use std::path::PathBuf;
 
     /// https://github.com/rojo-rbx/rojo/issues/899
     #[test]
@@ -492,4 +599,62 @@ mod test {
             "bar\nfoo\n\n"
         );
     }
+
+    /// https://github.com/rojo-rbx/rojo/issues/1200
+    #[test]
+    fn canonicalize_in_memory_success() {
+        let mut imfs = InMemoryFs::new();
+        let contents = "Lorem ipsum dolor sit amet.".to_string();
+
+        imfs.load_snapshot("/test/file.txt", VfsSnapshot::file(contents.to_string()))
+            .unwrap();
+
+        let vfs = Vfs::new(imfs);
+
+        assert_eq!(
+            vfs.canonicalize("/test/nested/../file.txt").unwrap(),
+            PathBuf::from("/test/file.txt")
+        );
+        assert_eq!(
+            vfs.read_to_string(vfs.canonicalize("/test/nested/../file.txt").unwrap())
+                .unwrap()
+                .to_string(),
+            contents.to_string()
+        );
+    }
+
+    #[test]
+    fn canonicalize_in_memory_missing_errors() {
+        let imfs = InMemoryFs::new();
+        let vfs = Vfs::new(imfs);
+
+        let err = vfs.canonicalize("test").unwrap_err();
+        assert_eq!(err.kind(), io::ErrorKind::NotFound);
+    }
+
+    #[test]
+    fn canonicalize_std_backend_success() {
+        let contents = "Lorem ipsum dolor sit amet.".to_string();
+        let dir = tempfile::tempdir().unwrap();
+        let file_path = dir.path().join("file.txt");
+        fs_err::write(&file_path, contents.to_string()).unwrap();
+
+        let vfs = Vfs::new(StdBackend::new());
+        let canonicalized = vfs.canonicalize(&file_path).unwrap();
+        assert_eq!(canonicalized, file_path.canonicalize().unwrap());
+        assert_eq!(
+            vfs.read_to_string(&canonicalized).unwrap().to_string(),
+            contents.to_string()
+        );
+    }
+
+    #[test]
+    fn canonicalize_std_backend_missing_errors() {
+        let dir = tempfile::tempdir().unwrap();
+        let file_path = dir.path().join("test");
+
+        let vfs = Vfs::new(StdBackend::new());
+        let err = vfs.canonicalize(&file_path).unwrap_err();
+        assert_eq!(err.kind(), io::ErrorKind::NotFound);
+    }
 }

crates/memofs/src/noop_backend.rs

@@ -1,5 +1,5 @@
 use std::io;
-use std::path::Path;
+use std::path::{Path, PathBuf};
 
 use crate::{Metadata, ReadDir, VfsBackend, VfsEvent};
 
@@ -15,45 +15,43 @@ impl NoopBackend {
 
 impl VfsBackend for NoopBackend {
     fn read(&mut self, _path: &Path) -> io::Result<Vec<u8>> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
-            "NoopBackend doesn't do anything",
-        ))
     }
 
     fn write(&mut self, _path: &Path, _data: &[u8]) -> io::Result<()> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
+    }
-            "NoopBackend doesn't do anything",
+
-        ))
+    fn exists(&mut self, _path: &Path) -> io::Result<bool> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
     }
 
     fn read_dir(&mut self, _path: &Path) -> io::Result<ReadDir> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
+    }
-            "NoopBackend doesn't do anything",
+
-        ))
+    fn create_dir(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
+    }
+
+    fn create_dir_all(&mut self, _path: &Path) -> io::Result<()> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
     }
 
     fn remove_file(&mut self, _path: &Path) -> io::Result<()> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
-            "NoopBackend doesn't do anything",
-        ))
     }
 
     fn remove_dir_all(&mut self, _path: &Path) -> io::Result<()> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
-            "NoopBackend doesn't do anything",
-        ))
     }
 
     fn metadata(&mut self, _path: &Path) -> io::Result<Metadata> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
+    }
-            "NoopBackend doesn't do anything",
+
-        ))
+    fn canonicalize(&mut self, _path: &Path) -> io::Result<PathBuf> {
+        Err(io::Error::other("NoopBackend doesn't do anything"))
     }
 
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
@@ -61,17 +59,11 @@ impl VfsBackend for NoopBackend {
     }
 
     fn watch(&mut self, _path: &Path) -> io::Result<()> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
-            "NoopBackend doesn't do anything",
-        ))
     }
 
     fn unwatch(&mut self, _path: &Path) -> io::Result<()> {
-        Err(io::Error::new(
+        Err(io::Error::other("NoopBackend doesn't do anything"))
-            io::ErrorKind::Other,
-            "NoopBackend doesn't do anything",
-        ))
     }
 }
 

crates/memofs/src/std_backend.rs

@@ -63,6 +63,10 @@ impl VfsBackend for StdBackend {
         fs_err::write(path, data)
     }
 
+    fn exists(&mut self, path: &Path) -> io::Result<bool> {
+        std::fs::exists(path)
+    }
+
     fn read_dir(&mut self, path: &Path) -> io::Result<ReadDir> {
         let entries: Result<Vec<_>, _> = fs_err::read_dir(path)?.collect();
         let mut entries = entries?;
@@ -78,6 +82,14 @@ impl VfsBackend for StdBackend {
         })
     }
 
+    fn create_dir(&mut self, path: &Path) -> io::Result<()> {
+        fs_err::create_dir(path)
+    }
+
+    fn create_dir_all(&mut self, path: &Path) -> io::Result<()> {
+        fs_err::create_dir_all(path)
+    }
+
     fn remove_file(&mut self, path: &Path) -> io::Result<()> {
         fs_err::remove_file(path)
     }
@@ -94,6 +106,10 @@ impl VfsBackend for StdBackend {
         })
     }
 
+    fn canonicalize(&mut self, path: &Path) -> io::Result<PathBuf> {
+        fs_err::canonicalize(path)
+    }
+
     fn event_receiver(&self) -> crossbeam_channel::Receiver<VfsEvent> {
         self.watcher_receiver.clone()
     }
@@ -109,15 +125,13 @@ impl VfsBackend for StdBackend {
             self.watches.insert(path.to_path_buf());
             self.watcher
                 .watch(path, RecursiveMode::Recursive)
-                .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
+                .map_err(io::Error::other)
         }
     }
 
     fn unwatch(&mut self, path: &Path) -> io::Result<()> {
         self.watches.remove(path);
-        self.watcher
+        self.watcher.unwatch(path).map_err(io::Error::other)
-            .unwatch(path)
-            .map_err(|inner| io::Error::new(io::ErrorKind::Other, inner))
     }
 }
 

crates/rojo-insta-ext/src/redaction_map.rs

@@ -22,6 +22,12 @@ impl RedactionMap {
         }
     }
 
+    /// Returns the numeric ID that was assigned to the provided value,
+    /// if one exists.
+    pub fn get_id_for_value(&self, value: impl ToString) -> Option<usize> {
+        self.ids.get(&value.to_string()).cloned()
+    }
+
     pub fn intern(&mut self, id: impl ToString) {
         let last_id = &mut self.last_id;
 

plugin/Version.txt

@@ -1 +1 @@
-7.5.1
+7.7.0-rc.1

plugin/fmt/init.lua

@@ -25,7 +25,7 @@
 local function defaultTableDebug(buffer, input)
 	buffer:writeRaw("{")
 
-	for key, value in pairs(input) do
+	for key, value in input do
 		buffer:write("[{:?}] = {:?}", key, value)
 
 		if next(input, key) ~= nil then
@@ -50,7 +50,7 @@ local function defaultTableDebugExtended(buffer, input)
 	buffer:writeLineRaw("{")
 	buffer:indent()
 
-	for key, value in pairs(input) do
+	for key, value in input do
 		buffer:writeLine("[{:?}] = {:#?},", key, value)
 	end
 

plugin/rbx_dom_lua/EncodedValue.lua

@@ -378,13 +378,26 @@ types = {
 			if pod == "Default" then
 				return nil
 			else
-				return PhysicalProperties.new(
+				-- Passing `nil` instead of not passing anything gives
-					pod.density,
+				-- different results, so we have to branch here.
-					pod.friction,
+				if pod.acousticAbsorption then
-					pod.elasticity,
+					return (PhysicalProperties.new :: any)(
-					pod.frictionWeight,
+						pod.density,
-					pod.elasticityWeight
+						pod.friction,
-				)
+						pod.elasticity,
+						pod.frictionWeight,
+						pod.elasticityWeight,
+						pod.acousticAbsorption
+					)
+				else
+					return PhysicalProperties.new(
+						pod.density,
+						pod.friction,
+						pod.elasticity,
+						pod.frictionWeight,
+						pod.elasticityWeight
+					)
+				end
 			end
 		end,
 
@@ -398,6 +411,7 @@ types = {
 					elasticity = roblox.Elasticity,
 					frictionWeight = roblox.FrictionWeight,
 					elasticityWeight = roblox.ElasticityWeight,
+					acousticAbsorption = roblox.AcousticAbsorption,
 				}
 			end
 		end,

plugin/rbx_dom_lua/allValues.json

@@ -441,7 +441,8 @@
         "friction": 1.0,
         "elasticity": 0.0,
         "frictionWeight": 50.0,
-        "elasticityWeight": 25.0
+        "elasticityWeight": 25.0,
+        "acousticAbsorption": 0.15625
       }
     },
     "ty": "PhysicalProperties"

plugin/rbx_dom_lua/base64.lua

@@ -1,139 +1,10 @@
--- Thanks to Tiffany352 for this base64 implementation!
+local EncodingService = game:GetService("EncodingService")
-
-local floor = math.floor
-local char = string.char
-
-local function encodeBase64(str)
-	local out = {}
-	local nOut = 0
-	local alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
-	local strLen = #str
-
-	-- 3 octets become 4 hextets
-	for i = 1, strLen - 2, 3 do
-		local b1, b2, b3 = str:byte(i, i + 3)
-		local word = b3 + b2 * 256 + b1 * 256 * 256
-
-		local h4 = word % 64 + 1
-		word = floor(word / 64)
-		local h3 = word % 64 + 1
-		word = floor(word / 64)
-		local h2 = word % 64 + 1
-		word = floor(word / 64)
-		local h1 = word % 64 + 1
-
-		out[nOut + 1] = alphabet:sub(h1, h1)
-		out[nOut + 2] = alphabet:sub(h2, h2)
-		out[nOut + 3] = alphabet:sub(h3, h3)
-		out[nOut + 4] = alphabet:sub(h4, h4)
-		nOut = nOut + 4
-	end
-
-	local remainder = strLen % 3
-
-	if remainder == 2 then
-		-- 16 input bits -> 3 hextets (2 full, 1 partial)
-		local b1, b2 = str:byte(-2, -1)
-		-- partial is 4 bits long, leaving 2 bits of zero padding ->
-		-- offset = 4
-		local word = b2 * 4 + b1 * 4 * 256
-
-		local h3 = word % 64 + 1
-		word = floor(word / 64)
-		local h2 = word % 64 + 1
-		word = floor(word / 64)
-		local h1 = word % 64 + 1
-
-		out[nOut + 1] = alphabet:sub(h1, h1)
-		out[nOut + 2] = alphabet:sub(h2, h2)
-		out[nOut + 3] = alphabet:sub(h3, h3)
-		out[nOut + 4] = "="
-	elseif remainder == 1 then
-		-- 8 input bits -> 2 hextets (2 full, 1 partial)
-		local b1 = str:byte(-1, -1)
-		-- partial is 2 bits long, leaving 4 bits of zero padding ->
-		-- offset = 16
-		local word = b1 * 16
-
-		local h2 = word % 64 + 1
-		word = floor(word / 64)
-		local h1 = word % 64 + 1
-
-		out[nOut + 1] = alphabet:sub(h1, h1)
-		out[nOut + 2] = alphabet:sub(h2, h2)
-		out[nOut + 3] = "="
-		out[nOut + 4] = "="
-	end
-	-- if the remainder is 0, then no work is needed
-
-	return table.concat(out, "")
-end
-
-local function decodeBase64(str)
-	local out = {}
-	local nOut = 0
-	local alphabet = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
-	local strLen = #str
-	local acc = 0
-	local nAcc = 0
-
-	local alphabetLut = {}
-	for i = 1, #alphabet do
-		alphabetLut[alphabet:sub(i, i)] = i - 1
-	end
-
-	-- 4 hextets become 3 octets
-	for i = 1, strLen do
-		local ch = str:sub(i, i)
-		local byte = alphabetLut[ch]
-		if byte then
-			acc = acc * 64 + byte
-			nAcc = nAcc + 1
-		end
-
-		if nAcc == 4 then
-			local b3 = acc % 256
-			acc = floor(acc / 256)
-			local b2 = acc % 256
-			acc = floor(acc / 256)
-			local b1 = acc % 256
-
-			out[nOut + 1] = char(b1)
-			out[nOut + 2] = char(b2)
-			out[nOut + 3] = char(b3)
-			nOut = nOut + 3
-			nAcc = 0
-			acc = 0
-		end
-	end
-
-	if nAcc == 3 then
-		-- 3 hextets -> 16 bit output
-		acc = acc * 64
-		acc = floor(acc / 256)
-		local b2 = acc % 256
-		acc = floor(acc / 256)
-		local b1 = acc % 256
-
-		out[nOut + 1] = char(b1)
-		out[nOut + 2] = char(b2)
-	elseif nAcc == 2 then
-		-- 2 hextets -> 8 bit output
-		acc = acc * 64
-		acc = floor(acc / 256)
-		acc = acc * 64
-		acc = floor(acc / 256)
-		local b1 = acc % 256
-
-		out[nOut + 1] = char(b1)
-	elseif nAcc == 1 then
-		error("Base64 has invalid length")
-	end
-
-	return table.concat(out, "")
-end
 
 return {
-	decode = decodeBase64,
+	decode = function(input: string)
-	encode = encodeBase64,
+		return buffer.tostring(EncodingService:Base64Decode(buffer.fromstring(input)))
+	end,
+	encode = function(input: string)
+		return buffer.tostring(EncodingService:Base64Encode(buffer.fromstring(input)))
+	end,
 }

plugin/rbx_dom_lua/customProperties.lua

@@ -208,4 +208,30 @@ return {
 			end,
 		},
 	},
+	StyleRule = {
+		PropertiesSerialize = {
+			read = function(instance: StyleRule)
+				return true, instance:GetProperties()
+			end,
+			write = function(instance: StyleRule, _, value: { [any]: any })
+				if typeof(value) ~= "table" then
+					return false, Error.new(Error.Kind.CannotParseBinaryString)
+				end
+
+				local existing = instance:GetProperties()
+
+				for itemName, itemValue in pairs(value) do
+					instance:SetProperty(itemName, itemValue)
+				end
+
+				for existingItemName in pairs(existing) do
+					if value[existingItemName] == nil then
+						instance:SetProperty(existingItemName, nil)
+					end
+				end
+
+				return true
+			end,
+		},
+	},
 }

plugin/src/ApiContext.lua

@@ -1,4 +1,5 @@
 local Packages = script.Parent.Parent.Packages
+local HttpService = game:GetService("HttpService")
 local Http = require(Packages.Http)
 local Log = require(Packages.Log)
 local Promise = require(Packages.Promise)
@@ -9,7 +10,9 @@ local Version = require(script.Parent.Version)
 
 local validateApiInfo = Types.ifEnabled(Types.ApiInfoResponse)
 local validateApiRead = Types.ifEnabled(Types.ApiReadResponse)
-local validateApiSubscribe = Types.ifEnabled(Types.ApiSubscribeResponse)
+local validateApiSocketPacket = Types.ifEnabled(Types.ApiSocketPacket)
+local validateApiSerialize = Types.ifEnabled(Types.ApiSerializeResponse)
+local validateApiRefPatch = Types.ifEnabled(Types.ApiRefPatchResponse)
 
 local function rejectFailedRequests(response)
 	if response.code >= 400 then
@@ -97,6 +100,7 @@ function ApiContext.new(baseUrl)
 		__baseUrl = baseUrl,
 		__sessionId = nil,
 		__messageCursor = -1,
+		__wsClient = nil,
 		__connected = true,
 		__activeRequests = {},
 	}
@@ -124,6 +128,12 @@ function ApiContext:disconnect()
 		request:cancel()
 	end
 	self.__activeRequests = {}
+
+	if self.__wsClient then
+		Log.trace("Closing WebSocket client")
+		self.__wsClient:Close()
+	end
+	self.__wsClient = nil
 end
 
 function ApiContext:setMessageCursor(index)
@@ -205,38 +215,65 @@ function ApiContext:write(patch)
 	end)
 end
 
-function ApiContext:retrieveMessages()
+function ApiContext:connectWebSocket(packetHandlers)
-	local url = ("%s/api/subscribe/%s"):format(self.__baseUrl, self.__messageCursor)
+	local url = ("%s/api/socket/%s"):format(self.__baseUrl, self.__messageCursor)
+	-- Convert HTTP/HTTPS URL to WS/WSS
+	url = url:gsub("^http://", "ws://"):gsub("^https://", "wss://")
 
-	local function sendRequest()
+	return Promise.new(function(resolve, reject)
-		local request = Http.get(url):catch(function(err)
+		local success, wsClient =
-			if err.type == Http.Error.Kind.Timeout and self.__connected then
+			pcall(HttpService.CreateWebStreamClient, HttpService, Enum.WebStreamClientType.WebSocket, {
-				return sendRequest()
+				Url = url,
+			})
+		if not success then
+			reject("Failed to create WebSocket client: " .. tostring(wsClient))
+			return
+		end
+		self.__wsClient = wsClient
+
+		local closed, errored, received
+
+		received = self.__wsClient.MessageReceived:Connect(function(msg)
+			local data = Http.jsonDecode(msg)
+			if data.sessionId ~= self.__sessionId then
+				Log.warn("Received message with wrong session ID; ignoring")
+				return
 			end
 
-			return Promise.reject(err)
+			assert(validateApiSocketPacket(data))
+
+			Log.trace("Received websocket packet: {:#?}", data)
+
+			local handler = packetHandlers[data.packetType]
+			if handler then
+				local ok, err = pcall(handler, data.body)
+				if not ok then
+					Log.error("Error in WebSocket packet handler for type '%s': %s", data.packetType, err)
+				end
+			else
+				Log.warn("No handler for WebSocket packet type '%s'", data.packetType)
+			end
 		end)
 
-		Log.trace("Tracking request {}", request)
+		closed = self.__wsClient.Closed:Connect(function()
-		self.__activeRequests[request] = true
+			closed:Disconnect()
+			errored:Disconnect()
+			received:Disconnect()
 
-		return request:finally(function(...)
+			if self.__connected then
-			Log.trace("Cleaning up request {}", request)
+				reject("WebSocket connection closed unexpectedly")
-			self.__activeRequests[request] = nil
+			else
-			return ...
+				resolve()
+			end
 		end)
-	end
 
-	return sendRequest():andThen(rejectFailedRequests):andThen(Http.Response.json):andThen(function(body)
+		errored = self.__wsClient.Error:Connect(function(code, msg)
-		if body.sessionId ~= self.__sessionId then
+			closed:Disconnect()
-			return Promise.reject("Server changed ID")
+			errored:Disconnect()
-		end
+			received:Disconnect()
 
-		assert(validateApiSubscribe(body))
+			reject("WebSocket error: " .. code .. " - " .. msg)
-
+		end)
-		self:setMessageCursor(body.messageCursor)
-
-		return body.messages
 	end)
 end
 
@@ -252,4 +289,40 @@ function ApiContext:open(id)
 	end)
 end
 
+function ApiContext:serialize(ids: { string })
+	local url = ("%s/api/serialize"):format(self.__baseUrl)
+	local request_body = Http.jsonEncode({ sessionId = self.__sessionId, ids = ids })
+
+	return Http.post(url, request_body)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(response_body)
+			if response_body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
+
+			assert(validateApiSerialize(response_body))
+
+			return response_body
+		end)
+end
+
+function ApiContext:refPatch(ids: { string })
+	local url = ("%s/api/ref-patch"):format(self.__baseUrl)
+	local request_body = Http.jsonEncode({ sessionId = self.__sessionId, ids = ids })
+
+	return Http.post(url, request_body)
+		:andThen(rejectFailedRequests)
+		:andThen(Http.Response.json)
+		:andThen(function(response_body)
+			if response_body.sessionId ~= self.__sessionId then
+				return Promise.reject("Server changed ID")
+			end
+
+			assert(validateApiRefPatch(response_body))
+
+			return response_body
+		end)
+end
+
 return ApiContext

plugin/src/App/Components/ClassIcon.lua

@@ -1,6 +1,11 @@
 local StudioService = game:GetService("StudioService")
 local AssetService = game:GetService("AssetService")
 
+type CachedImageInfo = {
+	pixels: buffer,
+	size: Vector2,
+}
+
 local Rojo = script:FindFirstAncestor("Rojo")
 local Plugin = Rojo.Plugin
 local Packages = Rojo.Packages
@@ -11,44 +16,71 @@ local e = Roact.createElement
 
 local EditableImage = require(Plugin.App.Components.EditableImage)
 
-local imageCache = {}
+local imageCache: { [string]: CachedImageInfo } = {}
-local function getImageSizeAndPixels(image)
+
-	if not imageCache[image] then
+local function cloneBuffer(b: buffer): buffer
-		local editableImage = AssetService:CreateEditableImageAsync(image)
+	local newBuffer = buffer.create(buffer.len(b))
+	buffer.copy(newBuffer, 0, b)
+	return newBuffer
+end
+
+local function getImageSizeAndPixels(image: string): (Vector2, buffer)
+	local cachedImage = imageCache[image]
+
+	if not cachedImage then
+		local editableImage = AssetService:CreateEditableImageAsync(Content.fromUri(image))
+		local size = editableImage.Size
+		local pixels = editableImage:ReadPixelsBuffer(Vector2.zero, size)
 		imageCache[image] = {
-			Size = editableImage.Size,
+			pixels = pixels,
-			Pixels = editableImage:ReadPixels(Vector2.zero, editableImage.Size),
+			size = size,
 		}
+
+		return size, cloneBuffer(pixels)
 	end
 
-	return imageCache[image].Size, table.clone(imageCache[image].Pixels)
+	return cachedImage.size, cloneBuffer(cachedImage.pixels)
 end
 
 local function getRecoloredClassIcon(className, color)
 	local iconProps = StudioService:GetClassIcon(className)
 
 	if iconProps and color then
-		local success, editableImageSize, editableImagePixels = pcall(function()
+		--stylua: ignore
-			local size, pixels = getImageSizeAndPixels(iconProps.Image)
+		local success, editableImageSize, editableImagePixels = pcall(function(_iconProps: { [any]: any }, _color: Color3): (Vector2, buffer)
+			local size, pixels = getImageSizeAndPixels(_iconProps.Image)
+			local pixelsLen = buffer.len(pixels)
 
 			local minVal, maxVal = math.huge, -math.huge
-			for i = 1, #pixels, 4 do
+
-				if pixels[i + 3] == 0 then
+			for i = 0, pixelsLen, 4 do
+				if buffer.readu8(pixels, i + 3) == 0 then
 					continue
 				end
-				local pixelVal = math.max(pixels[i], pixels[i + 1], pixels[i + 2])
+				local pixelVal = math.max(
+					buffer.readu8(pixels, i),
+					buffer.readu8(pixels, i + 1),
+					buffer.readu8(pixels, i + 2)
+				)
 
 				minVal = math.min(minVal, pixelVal)
 				maxVal = math.max(maxVal, pixelVal)
 			end
 
-			local hue, sat, val = color:ToHSV()
+			local hue, sat, val = _color:ToHSV()
-			for i = 1, #pixels, 4 do
+
-				if pixels[i + 3] == 0 then
+			for i = 0, pixelsLen, 4 do
+				if buffer.readu8(pixels, i + 3) == 0 then
 					continue
 				end
+				local gIndex = i + 1
+				local bIndex = i + 2
 
-				local pixelVal = math.max(pixels[i], pixels[i + 1], pixels[i + 2])
+				local pixelVal = math.max(
+					buffer.readu8(pixels, i),
+					buffer.readu8(pixels, gIndex),
+					buffer.readu8(pixels, bIndex)
+				)
 				local newVal = val
 				if minVal < maxVal then
 					-- Remap minVal - maxVal to val*0.9 - val
@@ -56,10 +88,12 @@ local function getRecoloredClassIcon(className, color)
 				end
 
 				local newPixelColor = Color3.fromHSV(hue, sat, newVal)
-				pixels[i], pixels[i + 1], pixels[i + 2] = newPixelColor.R, newPixelColor.G, newPixelColor.B
+				buffer.writeu8(pixels, i, newPixelColor.R)
+				buffer.writeu8(pixels, gIndex, newPixelColor.G)
+				buffer.writeu8(pixels, bIndex, newPixelColor.B)
 			end
 			return size, pixels
-		end)
+		end, iconProps, color)
 		if success then
 			iconProps.EditableImagePixels = editableImagePixels
 			iconProps.EditableImageSize = editableImageSize

plugin/src/App/Components/CodeLabel.lua

@@ -1,66 +0,0 @@
-local Rojo = script:FindFirstAncestor("Rojo")
-local Plugin = Rojo.Plugin
-local Packages = Rojo.Packages
-
-local Roact = require(Packages.Roact)
-local Highlighter = require(Packages.Highlighter)
-Highlighter.matchStudioSettings()
-
-local e = Roact.createElement
-
-local Theme = require(Plugin.App.Theme)
-
-local CodeLabel = Roact.PureComponent:extend("CodeLabel")
-
-function CodeLabel:init()
-	self.labelRef = Roact.createRef()
-	self.highlightsRef = Roact.createRef()
-end
-
-function CodeLabel:didMount()
-	Highlighter.highlight({
-		textObject = self.labelRef:getValue(),
-	})
-	self:updateHighlights()
-end
-
-function CodeLabel:didUpdate()
-	self:updateHighlights()
-end
-
-function CodeLabel:updateHighlights()
-	local highlights = self.highlightsRef:getValue()
-	if not highlights then
-		return
-	end
-
-	for _, lineLabel in highlights:GetChildren() do
-		local lineNum = tonumber(string.match(lineLabel.Name, "%d+") or "0")
-		lineLabel.BackgroundColor3 = self.props.lineBackground
-		lineLabel.BorderSizePixel = 0
-		lineLabel.BackgroundTransparency = if self.props.markedLines[lineNum] then 0.25 else 1
-	end
-end
-
-function CodeLabel:render()
-	return Theme.with(function(theme)
-		return e("TextLabel", {
-			Size = self.props.size,
-			Position = self.props.position,
-			Text = self.props.text,
-			BackgroundTransparency = 1,
-			FontFace = theme.Font.Code,
-			TextSize = theme.TextSize.Code,
-			TextXAlignment = Enum.TextXAlignment.Left,
-			TextYAlignment = Enum.TextYAlignment.Top,
-			TextColor3 = Color3.fromRGB(255, 255, 255),
-			[Roact.Ref] = self.labelRef,
-		}, {
-			SyntaxHighlights = e("Folder", {
-				[Roact.Ref] = self.highlightsRef,
-			}),
-		})
-	end)
-end
-
-return CodeLabel

plugin/src/App/Components/EditableImage.lua

@@ -12,7 +12,8 @@ function EditableImage:init()
 end
 
 function EditableImage:writePixels()
-	local image = self.ref.current
+	local image = self.ref.current :: EditableImage
+
 	if not image then
 		return
 	end
@@ -20,7 +21,7 @@ function EditableImage:writePixels()
 		return
 	end
 
-	image:WritePixels(Vector2.zero, self.props.size, self.props.pixels)
+	image:WritePixelsBuffer(Vector2.zero, self.props.size, self.props.pixels)
 end
 
 function EditableImage:render()

plugin/src/App/Components/Header.lua

@@ -9,8 +9,70 @@ local Assets = require(Plugin.Assets)
 local Config = require(Plugin.Config)
 local Version = require(Plugin.Version)
 
+local Tooltip = require(Plugin.App.Components.Tooltip)
+local SlicedImage = require(script.Parent.SlicedImage)
+
 local e = Roact.createElement
 
+local function VersionIndicator(props)
+	local updateMessage = Version.getUpdateMessage()
+
+	return Theme.with(function(theme)
+		return e("Frame", {
+			LayoutOrder = props.layoutOrder,
+			Size = UDim2.new(0, 0, 0, 25),
+			BackgroundTransparency = 1,
+			AutomaticSize = Enum.AutomaticSize.X,
+		}, {
+			Border = if updateMessage
+				then e(SlicedImage, {
+					slice = Assets.Slices.RoundedBorder,
+					color = theme.Button.Bordered.Enabled.BorderColor,
+					transparency = props.transparency,
+					size = UDim2.fromScale(1, 1),
+					zIndex = 0,
+				}, {
+					Indicator = e("ImageLabel", {
+						Size = UDim2.new(0, 10, 0, 10),
+						ScaleType = Enum.ScaleType.Fit,
+						Image = Assets.Images.Circles[16],
+						ImageColor3 = theme.Header.LogoColor,
+						ImageTransparency = props.transparency,
+						BackgroundTransparency = 1,
+						Position = UDim2.new(1, 0, 0, 0),
+						AnchorPoint = Vector2.new(0.5, 0.5),
+					}),
+				})
+				else nil,
+
+			Tip = if updateMessage
+				then e(Tooltip.Trigger, {
+					text = updateMessage,
+					delay = 0.1,
+				})
+				else nil,
+
+			VersionText = e("TextLabel", {
+				Text = Version.display(Config.version),
+				FontFace = theme.Font.Thin,
+				TextSize = theme.TextSize.Body,
+				TextColor3 = theme.Header.VersionColor,
+				TextXAlignment = Enum.TextXAlignment.Left,
+				TextTransparency = props.transparency,
+				BackgroundTransparency = 1,
+
+				Size = UDim2.new(0, 0, 1, 0),
+				AutomaticSize = Enum.AutomaticSize.X,
+			}, {
+				Padding = e("UIPadding", {
+					PaddingLeft = UDim.new(0, 6),
+					PaddingRight = UDim.new(0, 6),
+				}),
+			}),
+		})
+	end)
+end
+
 local function Header(props)
 	return Theme.with(function(theme)
 		return e("Frame", {
@@ -29,18 +91,9 @@ local function Header(props)
 				BackgroundTransparency = 1,
 			}),
 
-			Version = e("TextLabel", {
+			VersionIndicator = e(VersionIndicator, {
-				Text = Version.display(Config.version),
+				transparency = props.transparency,
-				FontFace = theme.Font.Thin,
+				layoutOrder = 2,
-				TextSize = theme.TextSize.Body,
-				TextColor3 = theme.Header.VersionColor,
-				TextXAlignment = Enum.TextXAlignment.Left,
-				TextTransparency = props.transparency,
-
-				Size = UDim2.new(1, 0, 0, theme.TextSize.Body),
-
-				LayoutOrder = 2,
-				BackgroundTransparency = 1,
 			}),
 
 			Layout = e("UIListLayout", {

plugin/src/App/Components/Notifications/FullscreenNotification.lua

@@ -0,0 +1,151 @@
+local StudioService = game:GetService("StudioService")
+
+local Rojo = script:FindFirstAncestor("Rojo")
+local Plugin = Rojo.Plugin
+local Packages = Rojo.Packages
+
+local Roact = require(Packages.Roact)
+local Log = require(Packages.Log)
+
+local Theme = require(Plugin.App.Theme)
+local Assets = require(Plugin.Assets)
+
+local TextButton = require(Plugin.App.Components.TextButton)
+
+local e = Roact.createElement
+
+local FullscreenNotification = Roact.Component:extend("FullscreeFullscreenNotificationnNotification")
+
+function FullscreenNotification:init()
+	self.transparency, self.setTransparency = Roact.createBinding(0)
+	self.lifetime = self.props.timeout
+end
+
+function FullscreenNotification:dismiss()
+	if self.props.onClose then
+		self.props.onClose()
+	end
+end
+
+function FullscreenNotification:didMount()
+	self.props.soundPlayer:play(Assets.Sounds.Notification)
+
+	self.timeout = task.spawn(function()
+		local clock = os.clock()
+		local seen = false
+		while task.wait(1 / 10) do
+			local now = os.clock()
+			local dt = now - clock
+			clock = now
+
+			if not seen then
+				seen = StudioService.ActiveScript == nil
+			end
+
+			if not seen then
+				-- Don't run down timer before being viewed
+				continue
+			end
+
+			self.lifetime -= dt
+			if self.lifetime <= 0 then
+				self:dismiss()
+				break
+			end
+		end
+
+		self.timeout = nil
+	end)
+end
+
+function FullscreenNotification:willUnmount()
+	if self.timeout and coroutine.status(self.timeout) ~= "dead" then
+		task.cancel(self.timeout)
+	end
+end
+
+function FullscreenNotification:render()
+	return Theme.with(function(theme)
+		local actionButtons = {}
+		if self.props.actions then
+			for key, action in self.props.actions do
+				actionButtons[key] = e(TextButton, {
+					text = action.text,
+					style = action.style,
+					onClick = function()
+						self:dismiss()
+						if action.onClick then
+							local success, err = pcall(action.onClick, self)
+							if not success then
+								Log.warn("Error in notification action: " .. tostring(err))
+							end
+						end
+					end,
+					layoutOrder = -action.layoutOrder,
+					transparency = self.transparency,
+				})
+			end
+		end
+
+		return e("Frame", {
+			BackgroundColor3 = theme.BackgroundColor,
+			Size = UDim2.fromScale(1, 1),
+			ZIndex = self.props.layoutOrder,
+		}, {
+			Padding = e("UIPadding", {
+				PaddingLeft = UDim.new(0, 17),
+				PaddingRight = UDim.new(0, 15),
+				PaddingTop = UDim.new(0, 10),
+				PaddingBottom = UDim.new(0, 10),
+			}),
+			Layout = e("UIListLayout", {
+				SortOrder = Enum.SortOrder.LayoutOrder,
+				FillDirection = Enum.FillDirection.Vertical,
+				HorizontalAlignment = Enum.HorizontalAlignment.Center,
+				VerticalAlignment = Enum.VerticalAlignment.Center,
+				Padding = UDim.new(0, 10),
+			}),
+			Logo = e("ImageLabel", {
+				ImageTransparency = self.transparency,
+				Image = Assets.Images.Logo,
+				ImageColor3 = theme.Header.LogoColor,
+				BackgroundTransparency = 1,
+				Size = UDim2.fromOffset(60, 27),
+				LayoutOrder = 1,
+			}),
+			Info = e("TextLabel", {
+				Text = self.props.text,
+				FontFace = theme.Font.Main,
+				TextSize = theme.TextSize.Body,
+				TextColor3 = theme.Notification.InfoColor,
+				TextTransparency = self.transparency,
+				TextXAlignment = Enum.TextXAlignment.Center,
+				TextYAlignment = Enum.TextYAlignment.Center,
+				TextWrapped = true,
+				BackgroundTransparency = 1,
+
+				AutomaticSize = Enum.AutomaticSize.Y,
+				Size = UDim2.fromScale(0.4, 0),
+				LayoutOrder = 2,
+			}),
+			Actions = if self.props.actions
+				then e("Frame", {
+					Size = UDim2.new(1, -40, 0, 37),
+					BackgroundTransparency = 1,
+					LayoutOrder = 3,
+				}, {
+					Layout = e("UIListLayout", {
+						FillDirection = Enum.FillDirection.Horizontal,
+						HorizontalAlignment = Enum.HorizontalAlignment.Center,
+						VerticalAlignment = Enum.VerticalAlignment.Center,
+						SortOrder = Enum.SortOrder.LayoutOrder,
+						Padding = UDim.new(0, 5),
+					}),
+					Buttons = Roact.createFragment(actionButtons),
+				})
+				else nil,
+		})
+	end)
+end
+
+return FullscreenNotification

plugin/src/App/Components/Notifications/Notification.lua

@@ -16,8 +16,6 @@ local getTextBoundsAsync = require(Plugin.App.getTextBoundsAsync)
 local BorderedContainer = require(Plugin.App.Components.BorderedContainer)
 local TextButton = require(Plugin.App.Components.TextButton)
 
-local baseClock = DateTime.now().UnixTimestampMillis
-
 local e = Roact.createElement
 
 local Notification = Roact.Component:extend("Notification")
@@ -77,7 +75,9 @@ function Notification:didMount()
 end
 
 function Notification:willUnmount()
-	task.cancel(self.timeout)
+	if self.timeout and coroutine.status(self.timeout) ~= "dead" then
+		task.cancel(self.timeout)
+	end
 end
 
 function Notification:render()
@@ -95,9 +95,12 @@ function Notification:render()
 					text = action.text,
 					style = action.style,
 					onClick = function()
-						local success, err = pcall(action.onClick, self)
+						self:dismiss()
-						if not success then
+						if action.onClick then
-							Log.warn("Error in notification action: " .. tostring(err))
+							local success, err = pcall(action.onClick, self)
+							if not success then
+								Log.warn("Error in notification action: " .. tostring(err))
+							end
 						end
 					end,
 					layoutOrder = -action.layoutOrder,
@@ -138,17 +141,17 @@ function Notification:render()
 		}, {
 			e(BorderedContainer, {
 				transparency = transparency,
-				size = UDim2.new(1, 0, 1, 0),
+				size = UDim2.fromScale(1, 1),
 			}, {
 				Contents = e("Frame", {
-					Size = UDim2.new(1, 0, 1, 0),
+					Size = UDim2.fromScale(1, 1),
 					BackgroundTransparency = 1,
 				}, {
 					Logo = e("ImageLabel", {
 						ImageTransparency = transparency,
 						Image = Assets.Images.PluginButton,
 						BackgroundTransparency = 1,
-						Size = UDim2.new(0, logoSize, 0, logoSize),
+						Size = UDim2.fromOffset(logoSize, logoSize),
 						Position = UDim2.new(0, 0, 0, 0),
 						AnchorPoint = Vector2.new(0, 0),
 					}),
@@ -171,7 +174,7 @@ function Notification:render()
 					Actions = if self.props.actions
 						then e("Frame", {
 							Size = UDim2.new(1, -40, 0, actionsY),
-							Position = UDim2.new(1, 0, 1, 0),
+							Position = UDim2.fromScale(1, 1),
 							AnchorPoint = Vector2.new(1, 1),
 							BackgroundTransparency = 1,
 						}, {
@@ -198,26 +201,4 @@ function Notification:render()
 	end)
 end
 
-local Notifications = Roact.Component:extend("Notifications")
+return Notification
-
-function Notifications:render()
-	local notifs = {}
-
-	for id, notif in self.props.notifications do
-		notifs["NotifID_" .. id] = e(Notification, {
-			soundPlayer = self.props.soundPlayer,
-			text = notif.text,
-			timestamp = notif.timestamp,
-			timeout = notif.timeout,
-			actions = notif.actions,
-			layoutOrder = (notif.timestamp - baseClock),
-			onClose = function()
-				self.props.onClose(id)
-			end,
-		})
-	end
-
-	return Roact.createFragment(notifs)
-end
-
-return Notifications

plugin/src/App/Components/Notifications/init.lua

@@ -0,0 +1,66 @@
+local Rojo = script:FindFirstAncestor("Rojo")
+
+local Packages = Rojo.Packages
+local Roact = require(Packages.Roact)
+
+local e = Roact.createElement
+
+local Notification = require(script.Notification)
+local FullscreenNotification = require(script.FullscreenNotification)
+
+local Notifications = Roact.Component:extend("Notifications")
+
+function Notifications:render()
+	local popupNotifs = {}
+	local fullscreenNotifs = {}
+
+	for id, notif in self.props.notifications do
+		local targetTable = if notif.isFullscreen then fullscreenNotifs else popupNotifs
+		local targetComponent = if notif.isFullscreen then FullscreenNotification else Notification
+		targetTable["NotifID_" .. id] = e(targetComponent, {
+			soundPlayer = self.props.soundPlayer,
+			text = notif.text,
+			timeout = notif.timeout,
+			actions = notif.actions,
+			layoutOrder = id,
+			onClose = function()
+				if notif.onClose then
+					notif.onClose()
+				end
+				self.props.onClose(id)
+			end,
+		})
+	end
+
+	return e("Frame", {
+		Size = UDim2.fromScale(1, 1),
+		BackgroundTransparency = 1,
+	}, {
+		Fullscreen = e("Frame", {
+			Size = UDim2.fromScale(1, 1),
+			BackgroundTransparency = 1,
+		}, {
+			notifs = Roact.createFragment(fullscreenNotifs),
+		}),
+		Popups = e("Frame", {
+			Size = UDim2.fromScale(1, 1),
+			BackgroundTransparency = 1,
+		}, {
+			Layout = e("UIListLayout", {
+				SortOrder = Enum.SortOrder.LayoutOrder,
+				HorizontalAlignment = Enum.HorizontalAlignment.Right,
+				VerticalAlignment = Enum.VerticalAlignment.Bottom,
+				Padding = UDim.new(0, 5),
+			}),
+			Padding = e("UIPadding", {
+				PaddingTop = UDim.new(0, 5),
+				PaddingBottom = UDim.new(0, 5),
+				PaddingLeft = UDim.new(0, 5),
+				PaddingRight = UDim.new(0, 5),
+			}),
+			notifs = Roact.createFragment(popupNotifs),
+		}),
+	})
+end
+
+return Notifications

plugin/src/App/Components/PatchVisualizer/DomLabel.lua

@@ -95,7 +95,7 @@ function DomLabel:render()
 	return Theme.with(function(theme)
 		local color = if props.isWarning
 			then theme.Diff.Warning
-			elseif props.patchType then theme.Diff[props.patchType]
+			elseif props.patchType then theme.Diff.Background[props.patchType]
 			else theme.TextColor
 
 		local indent = (depth - 1) * 12 + 15

plugin/src/App/Components/StringDiffVisualizer/StringDiff.lua

@@ -1,3 +1,4 @@
+--!strict
 --[[
     Based on DiffMatchPatch by Neil Fraser.
     https://github.com/google/diff-match-patch
@@ -67,8 +68,187 @@ function StringDiff.findDiffs(text1: string, text2: string): Diffs
 	end
 
 	-- Cleanup the diff
+	diffs = StringDiff._cleanupSemantic(diffs)
 	diffs = StringDiff._reorderAndMerge(diffs)
 
+	-- Remove any empty diffs
+	local cursor = 1
+	while cursor and diffs[cursor] do
+		if diffs[cursor].value == "" then
+			table.remove(diffs, cursor)
+		else
+			cursor += 1
+		end
+	end
+
+	return diffs
+end
+
+function StringDiff._computeDiff(text1: string, text2: string): Diffs
+	-- Assumes that the prefix and suffix have already been trimmed off
+	-- and shortcut returns have been made so these texts must be different
+
+	local text1Length, text2Length = #text1, #text2
+
+	if text1Length == 0 then
+		-- It's simply inserting all of text2 into text1
+		return { { actionType = StringDiff.ActionTypes.Insert, value = text2 } }
+	end
+
+	if text2Length == 0 then
+		-- It's simply deleting all of text1
+		return { { actionType = StringDiff.ActionTypes.Delete, value = text1 } }
+	end
+
+	local longText = if text1Length > text2Length then text1 else text2
+	local shortText = if text1Length > text2Length then text2 else text1
+	local shortTextLength = #shortText
+
+	-- Shortcut if the shorter string exists entirely inside the longer one
+	local indexOf = if shortTextLength == 0 then nil else string.find(longText, shortText, 1, true)
+	if indexOf ~= nil then
+		local diffs = {
+			{ actionType = StringDiff.ActionTypes.Insert, value = string.sub(longText, 1, indexOf - 1) },
+			{ actionType = StringDiff.ActionTypes.Equal, value = shortText },
+			{ actionType = StringDiff.ActionTypes.Insert, value = string.sub(longText, indexOf + shortTextLength) },
+		}
+		-- Swap insertions for deletions if diff is reversed
+		if text1Length > text2Length then
+			diffs[1].actionType, diffs[3].actionType = StringDiff.ActionTypes.Delete, StringDiff.ActionTypes.Delete
+		end
+		return diffs
+	end
+
+	if shortTextLength == 1 then
+		-- Single character string
+		-- After the previous shortcut, the character can't be an equality
+		return {
+			{ actionType = StringDiff.ActionTypes.Delete, value = text1 },
+			{ actionType = StringDiff.ActionTypes.Insert, value = text2 },
+		}
+	end
+
+	return StringDiff._bisect(text1, text2)
+end
+
+function StringDiff._cleanupSemantic(diffs: Diffs): Diffs
+	-- Reduce the number of edits by eliminating semantically trivial equalities.
+	local changes = false
+	local equalities = {} -- Stack of indices where equalities are found.
+	local equalitiesLength = 0 -- Keeping our own length var is faster.
+	local lastEquality: string? = nil
+	-- Always equal to diffs[equalities[equalitiesLength]].value
+	local pointer = 1 -- Index of current position.
+	-- Number of characters that changed prior to the equality.
+	local length_insertions1 = 0
+	local length_deletions1 = 0
+	-- Number of characters that changed after the equality.
+	local length_insertions2 = 0
+	local length_deletions2 = 0
+
+	while diffs[pointer] do
+		if diffs[pointer].actionType == StringDiff.ActionTypes.Equal then -- Equality found.
+			equalitiesLength = equalitiesLength + 1
+			equalities[equalitiesLength] = pointer
+			length_insertions1 = length_insertions2
+			length_deletions1 = length_deletions2
+			length_insertions2 = 0
+			length_deletions2 = 0
+			lastEquality = diffs[pointer].value
+		else -- An insertion or deletion.
+			if diffs[pointer].actionType == StringDiff.ActionTypes.Insert then
+				length_insertions2 = length_insertions2 + #diffs[pointer].value
+			else
+				length_deletions2 = length_deletions2 + #diffs[pointer].value
+			end
+			-- Eliminate an equality that is smaller or equal to the edits on both
+			-- sides of it.
+			if
+				lastEquality
+				and (#lastEquality <= math.max(length_insertions1, length_deletions1))
+				and (#lastEquality <= math.max(length_insertions2, length_deletions2))
+			then
+				-- Duplicate record.
+				table.insert(
+					diffs,
+					equalities[equalitiesLength],
+					{ actionType = StringDiff.ActionTypes.Delete, value = lastEquality }
+				)
+				-- Change second copy to insert.
+				diffs[equalities[equalitiesLength] + 1].actionType = StringDiff.ActionTypes.Insert
+				-- Throw away the equality we just deleted.
+				equalitiesLength = equalitiesLength - 1
+				-- Throw away the previous equality (it needs to be reevaluated).
+				equalitiesLength = equalitiesLength - 1
+				pointer = (equalitiesLength > 0) and equalities[equalitiesLength] or 0
+				length_insertions1, length_deletions1 = 0, 0 -- Reset the counters.
+				length_insertions2, length_deletions2 = 0, 0
+				lastEquality = nil
+				changes = true
+			end
+		end
+		pointer = pointer + 1
+	end
+
+	-- Normalize the diff.
+	if changes then
+		StringDiff._reorderAndMerge(diffs)
+	end
+	StringDiff._cleanupSemanticLossless(diffs)
+
+	-- Find any overlaps between deletions and insertions.
+	-- e.g: <del>abcxxx</del><ins>xxxdef</ins>
+	--   -> <del>abc</del>xxx<ins>def</ins>
+	-- e.g: <del>xxxabc</del><ins>defxxx</ins>
+	--   -> <ins>def</ins>xxx<del>abc</del>
+	-- Only extract an overlap if it is as big as the edit ahead or behind it.
+	pointer = 2
+	while diffs[pointer] do
+		if
+			diffs[pointer - 1].actionType == StringDiff.ActionTypes.Delete
+			and diffs[pointer].actionType == StringDiff.ActionTypes.Insert
+		then
+			local deletion = diffs[pointer - 1].value
+			local insertion = diffs[pointer].value
+			local overlap_length1 = StringDiff._commonOverlap(deletion, insertion)
+			local overlap_length2 = StringDiff._commonOverlap(insertion, deletion)
+			if overlap_length1 >= overlap_length2 then
+				if overlap_length1 >= #deletion / 2 or overlap_length1 >= #insertion / 2 then
+					-- Overlap found.  Insert an equality and trim the surrounding edits.
+					table.insert(
+						diffs,
+						pointer,
+						{ actionType = StringDiff.ActionTypes.Equal, value = string.sub(insertion, 1, overlap_length1) }
+					)
+					diffs[pointer - 1].value = string.sub(deletion, 1, #deletion - overlap_length1)
+					diffs[pointer + 1].value = string.sub(insertion, overlap_length1 + 1)
+					pointer = pointer + 1
+				end
+			else
+				if overlap_length2 >= #deletion / 2 or overlap_length2 >= #insertion / 2 then
+					-- Reverse overlap found.
+					-- Insert an equality and swap and trim the surrounding edits.
+					table.insert(
+						diffs,
+						pointer,
+						{ actionType = StringDiff.ActionTypes.Equal, value = string.sub(deletion, 1, overlap_length2) }
+					)
+					diffs[pointer - 1] = {
+						actionType = StringDiff.ActionTypes.Insert,
+						value = string.sub(insertion, 1, #insertion - overlap_length2),
+					}
+					diffs[pointer + 1] = {
+						actionType = StringDiff.ActionTypes.Delete,
+						value = string.sub(deletion, overlap_length2 + 1),
+					}
+					pointer = pointer + 1
+				end
+			end
+			pointer = pointer + 1
+		end
+		pointer = pointer + 1
+	end
+
 	return diffs
 end
 
@@ -124,51 +304,164 @@ function StringDiff._sharedSuffix(text1: string, text2: string): number
 	return pointerMid
 end
 
-function StringDiff._computeDiff(text1: string, text2: string): Diffs
+function StringDiff._commonOverlap(text1: string, text2: string): number
-	-- Assumes that the prefix and suffix have already been trimmed off
+	-- Determine if the suffix of one string is the prefix of another.
-	-- and shortcut returns have been made so these texts must be different
 
-	local text1Length, text2Length = #text1, #text2
+	-- Cache the text lengths to prevent multiple calls.
-
+	local text1_length = #text1
-	if text1Length == 0 then
+	local text2_length = #text2
-		-- It's simply inserting all of text2 into text1
+	-- Eliminate the null case.
-		return { { actionType = StringDiff.ActionTypes.Insert, value = text2 } }
+	if text1_length == 0 or text2_length == 0 then
+		return 0
+	end
+	-- Truncate the longer string.
+	if text1_length > text2_length then
+		text1 = string.sub(text1, text1_length - text2_length + 1)
+	elseif text1_length < text2_length then
+		text2 = string.sub(text2, 1, text1_length)
+	end
+	local text_length = math.min(text1_length, text2_length)
+	-- Quick check for the worst case.
+	if text1 == text2 then
+		return text_length
 	end
 
-	if text2Length == 0 then
+	-- Start by looking for a single character match
-		-- It's simply deleting all of text1
+	-- and increase length until no match is found.
-		return { { actionType = StringDiff.ActionTypes.Delete, value = text1 } }
+	-- Performance analysis: https://neil.fraser.name/news/2010/11/04/
-	end
+	local best = 0
-
+	local length = 1
-	local longText = if text1Length > text2Length then text1 else text2
+	while true do
-	local shortText = if text1Length > text2Length then text2 else text1
+		local pattern = string.sub(text1, text_length - length + 1)
-	local shortTextLength = #shortText
+		local found = string.find(text2, pattern, 1, true)
-
+		if found == nil then
-	-- Shortcut if the shorter string exists entirely inside the longer one
+			return best
-	local indexOf = if shortTextLength == 0 then nil else string.find(longText, shortText, 1, true)
-	if indexOf ~= nil then
-		local diffs = {
-			{ actionType = StringDiff.ActionTypes.Insert, value = string.sub(longText, 1, indexOf - 1) },
-			{ actionType = StringDiff.ActionTypes.Equal, value = shortText },
-			{ actionType = StringDiff.ActionTypes.Insert, value = string.sub(longText, indexOf + shortTextLength) },
-		}
-		-- Swap insertions for deletions if diff is reversed
-		if text1Length > text2Length then
-			diffs[1].actionType, diffs[3].actionType = StringDiff.ActionTypes.Delete, StringDiff.ActionTypes.Delete
 		end
-		return diffs
+		length = length + found - 1
+		if found == 1 or string.sub(text1, text_length - length + 1) == string.sub(text2, 1, length) then
+			best = length
+			length = length + 1
+		end
+	end
+end
+
+function StringDiff._cleanupSemanticScore(one: string, two: string): number
+	-- Given two strings, compute a score representing whether the internal
+	-- boundary falls on logical boundaries.
+	-- Scores range from 6 (best) to 0 (worst).
+
+	if (#one == 0) or (#two == 0) then
+		-- Edges are the best.
+		return 6
 	end
 
-	if shortTextLength == 1 then
+	-- Each port of this function behaves slightly differently due to
-		-- Single character string
+	-- subtle differences in each language's definition of things like
-		-- After the previous shortcut, the character can't be an equality
+	-- 'whitespace'.  Since this function's purpose is largely cosmetic,
-		return {
+	-- the choice has been made to use each language's native features
-			{ actionType = StringDiff.ActionTypes.Delete, value = text1 },
+	-- rather than force total conformity.
-			{ actionType = StringDiff.ActionTypes.Insert, value = text2 },
+	local char1 = string.sub(one, -1)
-		}
+	local char2 = string.sub(two, 1, 1)
-	end
+	local nonAlphaNumeric1 = string.match(char1, "%W")
+	local nonAlphaNumeric2 = string.match(char2, "%W")
+	local whitespace1 = nonAlphaNumeric1 and string.match(char1, "%s")
+	local whitespace2 = nonAlphaNumeric2 and string.match(char2, "%s")
+	local lineBreak1 = whitespace1 and string.match(char1, "%c")
+	local lineBreak2 = whitespace2 and string.match(char2, "%c")
+	local blankLine1 = lineBreak1 and string.match(one, "\n\r?\n$")
+	local blankLine2 = lineBreak2 and string.match(two, "^\r?\n\r?\n")
 
-	return StringDiff._bisect(text1, text2)
+	if blankLine1 or blankLine2 then
+		-- Five points for blank lines.
+		return 5
+	elseif lineBreak1 or lineBreak2 then
+		-- Four points for line breaks
+		-- DEVIATION: Prefer to start on a line break instead of end on it
+		return if lineBreak1 then 4 else 4.5
+	elseif nonAlphaNumeric1 and not whitespace1 and whitespace2 then
+		-- Three points for end of sentences.
+		return 3
+	elseif whitespace1 or whitespace2 then
+		-- Two points for whitespace.
+		return 2
+	elseif nonAlphaNumeric1 or nonAlphaNumeric2 then
+		-- One point for non-alphanumeric.
+		return 1
+	end
+	return 0
+end
+
+function StringDiff._cleanupSemanticLossless(diffs: Diffs)
+	-- Look for single edits surrounded on both sides by equalities
+	-- which can be shifted sideways to align the edit to a word boundary.
+	-- e.g: The c<ins>at c</ins>ame. -> The <ins>cat </ins>came.
+
+	local pointer = 2
+	-- Intentionally ignore the first and last element (don't need checking).
+	while diffs[pointer + 1] do
+		local prevDiff, nextDiff = diffs[pointer - 1], diffs[pointer + 1]
+		if
+			(prevDiff.actionType == StringDiff.ActionTypes.Equal)
+			and (nextDiff.actionType == StringDiff.ActionTypes.Equal)
+		then
+			-- This is a single edit surrounded by equalities.
+			local diff = diffs[pointer]
+
+			local equality1 = prevDiff.value
+			local edit = diff.value
+			local equality2 = nextDiff.value
+
+			-- First, shift the edit as far left as possible.
+			local commonOffset = StringDiff._sharedSuffix(equality1, edit)
+			if commonOffset > 0 then
+				local commonString = string.sub(edit, -commonOffset)
+				equality1 = string.sub(equality1, 1, -commonOffset - 1)
+				edit = commonString .. string.sub(edit, 1, -commonOffset - 1)
+				equality2 = commonString .. equality2
+			end
+
+			-- Second, step character by character right, looking for the best fit.
+			local bestEquality1 = equality1
+			local bestEdit = edit
+			local bestEquality2 = equality2
+			local bestScore = StringDiff._cleanupSemanticScore(equality1, edit)
+				+ StringDiff._cleanupSemanticScore(edit, equality2)
+
+			while string.byte(edit, 1) == string.byte(equality2, 1) do
+				equality1 = equality1 .. string.sub(edit, 1, 1)
+				edit = string.sub(edit, 2) .. string.sub(equality2, 1, 1)
+				equality2 = string.sub(equality2, 2)
+				local score = StringDiff._cleanupSemanticScore(equality1, edit)
+					+ StringDiff._cleanupSemanticScore(edit, equality2)
+				-- The > (rather than >=) encourages leading rather than trailing whitespace on edits.
+				-- I just think it looks better for indentation changes to start the line,
+				-- since then indenting several lines all have aligned diffs at the start
+				if score > bestScore then
+					bestScore = score
+					bestEquality1 = equality1
+					bestEdit = edit
+					bestEquality2 = equality2
+				end
+			end
+			if prevDiff.value ~= bestEquality1 then
+				-- We have an improvement, save it back to the diff.
+				if #bestEquality1 > 0 then
+					diffs[pointer - 1].value = bestEquality1
+				else
+					table.remove(diffs, pointer - 1)
+					pointer = pointer - 1
+				end
+				diffs[pointer].value = bestEdit
+				if #bestEquality2 > 0 then
+					diffs[pointer + 1].value = bestEquality2
+				else
+					table.remove(diffs, pointer + 1)
+					pointer = pointer - 1
+				end
+			end
+		end
+		pointer = pointer + 1
+	end
 end
 
 function StringDiff._bisect(text1: string, text2: string): Diffs

plugin/src/App/Components/StringDiffVisualizer/init.lua

@@ -5,15 +5,15 @@ local Packages = Rojo.Packages
 local Roact = require(Packages.Roact)
 local Log = require(Packages.Log)
 local Highlighter = require(Packages.Highlighter)
+Highlighter.matchStudioSettings()
 local StringDiff = require(script:FindFirstChild("StringDiff"))
 
 local Timer = require(Plugin.Timer)
 local Theme = require(Plugin.App.Theme)
 local getTextBoundsAsync = require(Plugin.App.getTextBoundsAsync)
 
-local CodeLabel = require(Plugin.App.Components.CodeLabel)
 local BorderedContainer = require(Plugin.App.Components.BorderedContainer)
-local ScrollingFrame = require(Plugin.App.Components.ScrollingFrame)
+local VirtualScroller = require(Plugin.App.Components.VirtualScroller)
 
 local e = Roact.createElement
 
@@ -21,26 +21,29 @@ local StringDiffVisualizer = Roact.Component:extend("StringDiffVisualizer")
 
 function StringDiffVisualizer:init()
 	self.scriptBackground, self.setScriptBackground = Roact.createBinding(Color3.fromRGB(0, 0, 0))
-	self.contentSize, self.setContentSize = Roact.createBinding(Vector2.new(0, 0))
+	self.updateEvent = Instance.new("BindableEvent")
+	self.lineHeight, self.setLineHeight = Roact.createBinding(15)
+	self.canvasPosition, self.setCanvasPosition = Roact.createBinding(Vector2.zero)
+	self.windowWidth, self.setWindowWidth = Roact.createBinding(math.huge)
 
 	-- Ensure that the script background is up to date with the current theme
 	self.themeChangedConnection = settings().Studio.ThemeChanged:Connect(function()
-		task.defer(function()
+		-- Delay to allow Highlighter to process the theme change first
-			-- Defer to allow Highlighter to process the theme change first
+		task.delay(1 / 20, function()
 			self:updateScriptBackground()
+			self:updateDiffs()
+			-- Rerender the virtual list elements
+			self.updateEvent:Fire()
 		end)
 	end)
 
 	self:updateScriptBackground()
-
+	self:updateDiffs()
-	self:setState({
-		add = {},
-		remove = {},
-	})
 end
 
 function StringDiffVisualizer:willUnmount()
 	self.themeChangedConnection:Disconnect()
+	self.updateEvent:Destroy()
 end
 
 function StringDiffVisualizer:updateScriptBackground()
@@ -51,96 +54,188 @@ function StringDiffVisualizer:updateScriptBackground()
 end
 
 function StringDiffVisualizer:didUpdate(previousProps)
-	if previousProps.oldString ~= self.props.oldString or previousProps.newString ~= self.props.newString then
+	if
-		local add, remove = self:calculateDiffLines()
+		previousProps.currentString ~= self.props.currentString
-		self:setState({
+		or previousProps.incomingString ~= self.props.incomingString
-			add = add,
+	then
-			remove = remove,
+		self:updateDiffs()
-		})
 	end
 end
 
-function StringDiffVisualizer:calculateContentSize(theme)
+function StringDiffVisualizer:updateDiffs()
-	local oldString, newString = self.props.oldString, self.props.newString
+	Timer.start("StringDiffVisualizer:updateDiffs")
-
+	local currentString, incomingString = self.props.currentString, self.props.incomingString
-	local oldStringBounds = getTextBoundsAsync(oldString, theme.Font.Code, theme.TextSize.Code, math.huge)
-	local newStringBounds = getTextBoundsAsync(newString, theme.Font.Code, theme.TextSize.Code, math.huge)
-
-	self.setContentSize(
-		Vector2.new(math.max(oldStringBounds.X, newStringBounds.X), math.max(oldStringBounds.Y, newStringBounds.Y))
-	)
-end
-
-function StringDiffVisualizer:calculateDiffLines()
-	Timer.start("StringDiffVisualizer:calculateDiffLines")
-	local oldString, newString = self.props.oldString, self.props.newString
 
 	-- Diff the two texts
 	local startClock = os.clock()
-	local diffs = StringDiff.findDiffs(oldString, newString)
+	local diffs =
+		StringDiff.findDiffs((string.gsub(currentString, "\t", "    ")), (string.gsub(incomingString, "\t", "    ")))
 	local stopClock = os.clock()
 
 	Log.trace(
 		"Diffing {} byte and {} byte strings took {} microseconds and found {} diff sections",
-		#oldString,
+		#currentString,
-		#newString,
+		#incomingString,
 		math.round((stopClock - startClock) * 1000 * 1000),
 		#diffs
 	)
 
-	-- Determine which lines to highlight
+	-- Build the rich text lines
-	local add, remove = {}, {}
+	local currentRichTextLines = Highlighter.buildRichTextLines({
+		src = currentString,
+	})
+	local incomingRichTextLines = Highlighter.buildRichTextLines({
+		src = incomingString,
+	})
 
-	local oldLineNum, newLineNum = 1, 1
+	local maxLines = math.max(#currentRichTextLines, #incomingRichTextLines)
+
+	-- Find the diff locations
+	local currentDiffs, incomingDiffs = {}, {}
+	local firstDiffLineNum = 0
+
+	local currentLineNum, incomingLineNum = 1, 1
+	local currentIdx, incomingIdx = 1, 1
 	for _, diff in diffs do
 		local actionType, text = diff.actionType, diff.value
-		local lines = select(2, string.gsub(text, "\n", "\n"))
+		local lineCount = select(2, string.gsub(text, "\n", "\n"))
+		local lines = string.split(text, "\n")
 
 		if actionType == StringDiff.ActionTypes.Equal then
-			oldLineNum += lines
+			if lineCount > 0 then
-			newLineNum += lines
+				-- Jump cursor ahead to last line
-		elseif actionType == StringDiff.ActionTypes.Insert then
+				currentLineNum += lineCount
-			if lines > 0 then
+				incomingLineNum += lineCount
-				local textLines = string.split(text, "\n")
+				currentIdx = #lines[#lines]
-				for i, textLine in textLines do
+				incomingIdx = #lines[#lines]
-					if string.match(textLine, "%S") then
-						add[newLineNum + i - 1] = true
-					end
-				end
 			else
-				if string.match(text, "%S") then
+				-- Move along this line
-					add[newLineNum] = true
+				currentIdx += #text
-				end
+				incomingIdx += #text
+			end
+
+			continue
+		end
+
+		if actionType == StringDiff.ActionTypes.Insert then
+			if firstDiffLineNum == 0 then
+				firstDiffLineNum = incomingLineNum
+			end
+
+			for i, lineText in lines do
+				if i > 1 then
+					-- Move to next line
+					incomingLineNum += 1
+					incomingIdx = 0
+				end
+				if not incomingDiffs[incomingLineNum] then
+					incomingDiffs[incomingLineNum] = {}
+				end
+				-- Mark these characters on this line
+				table.insert(incomingDiffs[incomingLineNum], {
+					start = incomingIdx,
+					stop = incomingIdx + #lineText,
+				})
+				incomingIdx += #lineText
 			end
-			newLineNum += lines
 		elseif actionType == StringDiff.ActionTypes.Delete then
-			if lines > 0 then
+			if firstDiffLineNum == 0 then
-				local textLines = string.split(text, "\n")
+				firstDiffLineNum = currentLineNum
-				for i, textLine in textLines do
+			end
-					if string.match(textLine, "%S") then
+
-						remove[oldLineNum + i - 1] = true
+			for i, lineText in lines do
-					end
+				if i > 1 then
-				end
+					-- Move to next line
-			else
+					currentLineNum += 1
-				if string.match(text, "%S") then
+					currentIdx = 0
-					remove[oldLineNum] = true
+				end
-				end
+				if not currentDiffs[currentLineNum] then
+					currentDiffs[currentLineNum] = {}
+				end
+				-- Mark these characters on this line
+				table.insert(currentDiffs[currentLineNum], {
+					start = currentIdx,
+					stop = currentIdx + #lineText,
+				})
+				currentIdx += #lineText
 			end
-			oldLineNum += lines
 		else
 			Log.warn("Unknown diff action: {} {}", actionType, text)
 		end
 	end
 
 	Timer.stop()
-	return add, remove
+
+	self:setState({
+		maxLines = maxLines,
+		currentRichTextLines = currentRichTextLines,
+		incomingRichTextLines = incomingRichTextLines,
+		currentDiffs = currentDiffs,
+		incomingDiffs = incomingDiffs,
+	})
+
+	-- Scroll to the first diff line
+	task.defer(self.setCanvasPosition, Vector2.new(0, math.max(0, (firstDiffLineNum - 4) * 16)))
 end
 
 function StringDiffVisualizer:render()
-	local oldString, newString = self.props.oldString, self.props.newString
+	local currentDiffs, incomingDiffs = self.state.currentDiffs, self.state.incomingDiffs
+	local currentRichTextLines, incomingRichTextLines =
+		self.state.currentRichTextLines, self.state.incomingRichTextLines
+	local maxLines = self.state.maxLines
 
 	return Theme.with(function(theme)
-		self:calculateContentSize(theme)
+		self.setLineHeight(theme.TextSize.Code)
+
+		-- Calculate the width of the canvas
+		-- (One line at a time to avoid the char limit of getTextBoundsAsync)
+		local canvasWidth = 0
+		for i = 1, maxLines do
+			local currentLine = currentRichTextLines[i]
+			if currentLine and string.find(currentLine, "%S") then
+				local bounds = getTextBoundsAsync(currentLine, theme.Font.Code, theme.TextSize.Code, math.huge, true)
+				if bounds.X > canvasWidth then
+					canvasWidth = bounds.X
+				end
+			end
+			local incomingLine = incomingRichTextLines[i]
+			if incomingLine and string.find(incomingLine, "%S") then
+				local bounds = getTextBoundsAsync(incomingLine, theme.Font.Code, theme.TextSize.Code, math.huge, true)
+				if bounds.X > canvasWidth then
+					canvasWidth = bounds.X
+				end
+			end
+		end
+
+		local lineNumberWidth =
+			getTextBoundsAsync(tostring(maxLines), theme.Font.Code, theme.TextSize.Body, math.huge, true).X
+
+		canvasWidth += lineNumberWidth + 12
+
+		local removalScrollMarkers = {}
+		local insertionScrollMarkers = {}
+		for lineNum in currentDiffs do
+			table.insert(
+				removalScrollMarkers,
+				e("Frame", {
+					Size = UDim2.fromScale(0.5, 1 / maxLines),
+					Position = UDim2.fromScale(0, (lineNum - 1) / maxLines),
+					BorderSizePixel = 0,
+					BackgroundColor3 = theme.Diff.Background.Remove,
+				})
+			)
+		end
+		for lineNum in incomingDiffs do
+			table.insert(
+				insertionScrollMarkers,
+				e("Frame", {
+					Size = UDim2.fromScale(0.5, 1 / maxLines),
+					Position = UDim2.fromScale(0.5, (lineNum - 1) / maxLines),
+					BorderSizePixel = 0,
+					BackgroundColor3 = theme.Diff.Background.Add,
+				})
+			)
+		end
 
 		return e(BorderedContainer, {
 			size = self.props.size,
@@ -159,43 +254,196 @@ function StringDiffVisualizer:render()
 					CornerRadius = UDim.new(0, 5),
 				}),
 			}),
-			Separator = e("Frame", {
+			Main = e("Frame", {
-				Size = UDim2.new(0, 2, 1, 0),
+				Size = UDim2.new(1, -10, 1, -2),
-				Position = UDim2.new(0.5, 0, 0, 0),
+				Position = UDim2.new(0, 2, 0, 2),
-				AnchorPoint = Vector2.new(0.5, 0),
+				BackgroundTransparency = 1,
-				BorderSizePixel = 0,
+				[Roact.Change.AbsoluteSize] = function(rbx)
-				BackgroundColor3 = theme.BorderedContainer.BorderColor,
+					self.setWindowWidth(rbx.AbsoluteSize.X * 0.5 - 10)
-				BackgroundTransparency = 0.5,
+				end,
-			}),
-			Old = e(ScrollingFrame, {
-				position = UDim2.new(0, 2, 0, 2),
-				size = UDim2.new(0.5, -7, 1, -4),
-				scrollingDirection = Enum.ScrollingDirection.XY,
-				transparency = self.props.transparency,
-				contentSize = self.contentSize,
 			}, {
-				Source = e(CodeLabel, {
+				Separator = e("Frame", {
-					size = UDim2.new(1, 0, 1, 0),
+					Size = UDim2.new(0, 2, 1, 0),
+					Position = UDim2.new(0.5, 0, 0, 0),
+					AnchorPoint = Vector2.new(0.5, 0),
+					BorderSizePixel = 0,
+					BackgroundColor3 = theme.BorderedContainer.BorderColor,
+					BackgroundTransparency = 0.5,
+				}),
+				Current = e(VirtualScroller, {
 					position = UDim2.new(0, 0, 0, 0),
-					text = oldString,
+					size = UDim2.new(0.5, -1, 1, 0),
-					lineBackground = theme.Diff.Remove,
+					transparency = self.props.transparency,
-					markedLines = self.state.remove,
+					count = maxLines,
+					updateEvent = self.updateEvent.Event,
+					canvasWidth = canvasWidth,
+					canvasPosition = self.canvasPosition,
+					onCanvasPositionChanged = self.setCanvasPosition,
+					render = function(i)
+						local lineDiffs = currentDiffs[i]
+						local diffFrames = table.create(if lineDiffs then #lineDiffs else 0)
+
+						-- Show diff markers over the specific changed characters
+						if lineDiffs then
+							local charWidth = math.round(theme.TextSize.Code * 0.5)
+							for diffIdx, diff in lineDiffs do
+								local start, stop = diff.start, diff.stop
+								diffFrames[diffIdx] = e("Frame", {
+									Size = if #lineDiffs == 1
+											and start == 0
+											and stop == 0
+										then UDim2.fromScale(1, 1)
+										else UDim2.new(
+											0,
+											math.max(charWidth * (stop - start), charWidth * 0.4),
+											1,
+											0
+										),
+									Position = UDim2.fromOffset(charWidth * start, 0),
+									BackgroundColor3 = theme.Diff.Background.Remove,
+									BackgroundTransparency = 0.85,
+									BorderSizePixel = 0,
+									ZIndex = -1,
+								})
+							end
+						end
+
+						return Roact.createFragment({
+							LineNumber = e("TextLabel", {
+								Size = UDim2.new(0, lineNumberWidth + 8, 1, 0),
+								Text = i,
+								BackgroundColor3 = Color3.new(0, 0, 0),
+								BackgroundTransparency = 0.9,
+								BorderSizePixel = 0,
+								FontFace = theme.Font.Code,
+								TextSize = theme.TextSize.Body,
+								TextColor3 = if lineDiffs then theme.Diff.Background.Remove else theme.SubTextColor,
+								TextXAlignment = Enum.TextXAlignment.Right,
+							}, {
+								Padding = e("UIPadding", { PaddingRight = UDim.new(0, 6) }),
+							}),
+							Content = e("Frame", {
+								Size = UDim2.new(1, -(lineNumberWidth + 10), 1, 0),
+								Position = UDim2.fromScale(1, 0),
+								AnchorPoint = Vector2.new(1, 0),
+								BackgroundColor3 = theme.Diff.Background.Remove,
+								BackgroundTransparency = if lineDiffs then 0.95 else 1,
+								BorderSizePixel = 0,
+							}, {
+								CodeLabel = e("TextLabel", {
+									Size = UDim2.fromScale(1, 1),
+									Position = UDim2.fromScale(0, 0),
+									Text = currentRichTextLines[i] or "",
+									RichText = true,
+									BackgroundTransparency = 1,
+									BorderSizePixel = 0,
+									FontFace = theme.Font.Code,
+									TextSize = theme.TextSize.Code,
+									TextXAlignment = Enum.TextXAlignment.Left,
+									TextYAlignment = Enum.TextYAlignment.Top,
+									TextColor3 = Color3.fromRGB(255, 255, 255),
+								}),
+								DiffFrames = Roact.createFragment(diffFrames),
+							}),
+						})
+					end,
+					getHeightBinding = function()
+						return self.lineHeight
+					end,
+				}),
+				Incoming = e(VirtualScroller, {
+					position = UDim2.new(0.5, 1, 0, 0),
+					size = UDim2.new(0.5, -1, 1, 0),
+					transparency = self.props.transparency,
+					count = maxLines,
+					updateEvent = self.updateEvent.Event,
+					canvasWidth = canvasWidth,
+					canvasPosition = self.canvasPosition,
+					onCanvasPositionChanged = self.setCanvasPosition,
+					render = function(i)
+						local lineDiffs = incomingDiffs[i]
+						local diffFrames = table.create(if lineDiffs then #lineDiffs else 0)
+
+						-- Show diff markers over the specific changed characters
+						if lineDiffs then
+							local charWidth = math.round(theme.TextSize.Code * 0.5)
+							for diffIdx, diff in lineDiffs do
+								local start, stop = diff.start, diff.stop
+								diffFrames[diffIdx] = e("Frame", {
+									Size = if #lineDiffs == 1
+											and start == 0
+											and stop == 0
+										then UDim2.fromScale(1, 1)
+										else UDim2.new(
+											0,
+											math.max(charWidth * (stop - start), charWidth * 0.4),
+											1,
+											0
+										),
+									Position = UDim2.fromOffset(charWidth * start, 0),
+									BackgroundColor3 = theme.Diff.Background.Add,
+									BackgroundTransparency = 0.85,
+									BorderSizePixel = 0,
+									ZIndex = -1,
+								})
+							end
+						end
+
+						return Roact.createFragment({
+							LineNumber = e("TextLabel", {
+								Size = UDim2.new(0, lineNumberWidth + 8, 1, 0),
+								Text = i,
+								BackgroundColor3 = Color3.new(0, 0, 0),
+								BackgroundTransparency = 0.9,
+								BorderSizePixel = 0,
+								FontFace = theme.Font.Code,
+								TextSize = theme.TextSize.Body,
+								TextColor3 = if lineDiffs then theme.Diff.Background.Add else theme.SubTextColor,
+								TextXAlignment = Enum.TextXAlignment.Right,
+							}, {
+								Padding = e("UIPadding", { PaddingRight = UDim.new(0, 6) }),
+							}),
+							Content = e("Frame", {
+								Size = UDim2.new(1, -(lineNumberWidth + 10), 1, 0),
+								Position = UDim2.fromScale(1, 0),
+								AnchorPoint = Vector2.new(1, 0),
+								BackgroundColor3 = theme.Diff.Background.Add,
+								BackgroundTransparency = if lineDiffs then 0.95 else 1,
+								BorderSizePixel = 0,
+							}, {
+								CodeLabel = e("TextLabel", {
+									Size = UDim2.fromScale(1, 1),
+									Position = UDim2.fromScale(0, 0),
+									Text = incomingRichTextLines[i] or "",
+									RichText = true,
+									BackgroundColor3 = theme.Diff.Background.Add,
+									BackgroundTransparency = 1,
+									BorderSizePixel = 0,
+									FontFace = theme.Font.Code,
+									TextSize = theme.TextSize.Code,
+									TextXAlignment = Enum.TextXAlignment.Left,
+									TextYAlignment = Enum.TextYAlignment.Top,
+									TextColor3 = Color3.fromRGB(255, 255, 255),
+								}),
+								DiffFrames = Roact.createFragment(diffFrames),
+							}),
+						})
+					end,
+					getHeightBinding = function()
+						return self.lineHeight
+					end,
 				}),
 			}),
-			New = e(ScrollingFrame, {
+			ScrollMarkers = e("Frame", {
-				position = UDim2.new(0.5, 5, 0, 2),
+				Size = self.windowWidth:map(function(windowWidth)
-				size = UDim2.new(0.5, -7, 1, -4),
+					return UDim2.new(0, 8, 1, -4 - (if canvasWidth > windowWidth then 10 else 0))
-				scrollingDirection = Enum.ScrollingDirection.XY,
+				end),
-				transparency = self.props.transparency,
+				Position = UDim2.new(1, -2, 0, 2),
-				contentSize = self.contentSize,
+				AnchorPoint = Vector2.new(1, 0),
+				BackgroundTransparency = 1,
 			}, {
-				Source = e(CodeLabel, {
+				insertions = Roact.createFragment(insertionScrollMarkers),
-					size = UDim2.new(1, 0, 1, 0),
+				removals = Roact.createFragment(removalScrollMarkers),
-					position = UDim2.new(0, 0, 0, 0),
-					text = newString,
-					lineBackground = theme.Diff.Add,
-					markedLines = self.state.add,
-				}),
 			}),
 		})
 	end)

plugin/src/App/Components/TableDiffVisualizer/Array.lua

@@ -93,7 +93,7 @@ function Array:render()
 				e("Frame", {
 					Size = UDim2.new(1, 0, 0, 25),
 					BackgroundTransparency = if patchType == "Remain" then 1 else self.props.transparency,
-					BackgroundColor3 = if patchType == "Remain" then theme.Diff.Row else theme.Diff[patchType],
+					BackgroundColor3 = theme.Diff.Background[patchType],
 					BorderSizePixel = 0,
 					LayoutOrder = i,
 				}, {

plugin/src/App/Components/TableDiffVisualizer/Dictionary.lua

@@ -91,9 +91,7 @@ function Dictionary:render()
 					LayoutOrder = order,
 					BorderSizePixel = 0,
 					BackgroundTransparency = if line.patchType == "Remain" then 1 else self.props.transparency,
-					BackgroundColor3 = if line.patchType == "Remain"
+					BackgroundColor3 = theme.Diff.Background[line.patchType],
-						then theme.Diff.Row
-						else theme.Diff[line.patchType],
 				}, {
 					DiffIcon = if line.patchType ~= "Remain"
 						then e("ImageLabel", {
@@ -114,7 +112,7 @@ function Dictionary:render()
 						TextXAlignment = Enum.TextXAlignment.Left,
 						FontFace = theme.Font.Main,
 						TextSize = theme.TextSize.Body,
-						TextColor3 = theme.Settings.Setting.DescriptionColor,
+						TextColor3 = theme.Diff.Text[line.patchType],
 						TextTruncate = Enum.TextTruncate.AtEnd,
 					}),
 					OldValue = e("Frame", {
@@ -125,7 +123,7 @@ function Dictionary:render()
 						e(DisplayValue, {
 							value = oldValue,
 							transparency = self.props.transparency,
-							textColor = theme.Settings.Setting.DescriptionColor,
+							textColor = theme.Diff.Text[line.patchType],
 						}),
 					}),
 					NewValue = e("Frame", {
@@ -136,7 +134,7 @@ function Dictionary:render()
 						e(DisplayValue, {
 							value = newValue,
 							transparency = self.props.transparency,
-							textColor = theme.Settings.Setting.DescriptionColor,
+							textColor = theme.Diff.Text[line.patchType],
 						}),
 					}),
 				})

plugin/src/App/Components/Tooltip.lua

@@ -216,7 +216,7 @@ function Trigger:managePopup()
 			return
 		end
 
-		self.showDelayThread = task.delay(DELAY, function()
+		self.showDelayThread = task.delay(self.props.delay or DELAY, function()
 			self.props.context.addTip(self.id, {
 				Text = self.props.text,
 				Position = self:getMousePos(),

plugin/src/App/Components/VirtualScroller.lua

@@ -15,8 +15,10 @@ local VirtualScroller = Roact.Component:extend("VirtualScroller")
 function VirtualScroller:init()
 	self.scrollFrameRef = Roact.createRef()
 	self:setState({
-		WindowSize = Vector2.new(),
+		WindowSize = Vector2.zero,
-		CanvasPosition = Vector2.new(),
+		CanvasPosition = if self.props.canvasPosition
+			then self.props.canvasPosition:getValue() or Vector2.zero
+			else Vector2.zero,
 	})
 
 	self.totalCanvas, self.setTotalCanvas = Roact.createBinding(0)
@@ -41,6 +43,10 @@ function VirtualScroller:didMount()
 
 	local canvasPositionSignal = rbx:GetPropertyChangedSignal("CanvasPosition")
 	self.canvasPositionChanged = canvasPositionSignal:Connect(function()
+		if self.props.onCanvasPositionChanged then
+			pcall(self.props.onCanvasPositionChanged, rbx.CanvasPosition)
+		end
+
 		if math.abs(rbx.CanvasPosition.Y - self.state.CanvasPosition.Y) > 5 then
 			self:setState({ CanvasPosition = rbx.CanvasPosition })
 			self:refresh()
@@ -134,8 +140,9 @@ function VirtualScroller:render()
 			BackgroundColor3 = props.backgroundColor3 or theme.BorderedContainer.BackgroundColor,
 			BorderColor3 = props.borderColor3 or theme.BorderedContainer.BorderColor,
 			CanvasSize = self.totalCanvas:map(function(s)
-				return UDim2.fromOffset(0, s)
+				return UDim2.fromOffset(props.canvasWidth or 0, s)
 			end),
+			CanvasPosition = self.props.canvasPosition,
 			ScrollBarThickness = 9,
 			ScrollBarImageColor3 = theme.ScrollBarColor,
 			ScrollBarImageTransparency = props.transparency:map(function(value)
@@ -146,7 +153,7 @@ function VirtualScroller:render()
 			BottomImage = Assets.Images.ScrollBar.Bottom,
 
 			ElasticBehavior = Enum.ElasticBehavior.Always,
-			ScrollingDirection = Enum.ScrollingDirection.Y,
+			ScrollingDirection = Enum.ScrollingDirection.XY,
 			VerticalScrollBarInset = Enum.ScrollBarInset.ScrollBar,
 			[Roact.Ref] = self.scrollFrameRef,
 		}, {

plugin/src/App/StatusPages/Confirming.lua

@@ -4,8 +4,6 @@ local Packages = Rojo.Packages
 
 local Roact = require(Packages.Roact)
 
-local Timer = require(Plugin.Timer)
-local PatchTree = require(Plugin.PatchTree)
 local Settings = require(Plugin.Settings)
 local Theme = require(Plugin.App.Theme)
 local TextButton = require(Plugin.App.Components.TextButton)
@@ -24,36 +22,13 @@ function ConfirmingPage:init()
 	self.containerSize, self.setContainerSize = Roact.createBinding(Vector2.new(0, 0))
 
 	self:setState({
-		patchTree = nil,
 		showingStringDiff = false,
-		oldString = "",
+		currentString = "",
-		newString = "",
+		incomingString = "",
 		showingTableDiff = false,
 		oldTable = {},
 		newTable = {},
 	})
-
-	if self.props.confirmData and self.props.confirmData.patch and self.props.confirmData.instanceMap then
-		self:buildPatchTree()
-	end
-end
-
-function ConfirmingPage:didUpdate(prevProps)
-	if prevProps.confirmData ~= self.props.confirmData then
-		self:buildPatchTree()
-	end
-end
-
-function ConfirmingPage:buildPatchTree()
-	Timer.start("ConfirmingPage:buildPatchTree")
-	self:setState({
-		patchTree = PatchTree.build(
-			self.props.confirmData.patch,
-			self.props.confirmData.instanceMap,
-			{ "Property", "Current", "Incoming" }
-		),
-	})
-	Timer.stop()
 end
 
 function ConfirmingPage:render()
@@ -79,13 +54,13 @@ function ConfirmingPage:render()
 				transparency = self.props.transparency,
 				layoutOrder = 3,
 
-				patchTree = self.state.patchTree,
+				patchTree = self.props.patchTree,
 
-				showStringDiff = function(oldString: string, newString: string)
+				showStringDiff = function(currentString: string, incomingString: string)
 					self:setState({
 						showingStringDiff = true,
-						oldString = oldString,
+						currentString = currentString,
-						newString = newString,
+						incomingString = incomingString,
 					})
 				end,
 				showTableDiff = function(oldTable: { [any]: any? }, newTable: { [any]: any? })
@@ -192,8 +167,8 @@ function ConfirmingPage:render()
 							anchorPoint = Vector2.new(0, 0),
 							transparency = self.props.transparency,
 
-							oldString = self.state.oldString,
+							currentString = self.state.currentString,
-							newString = self.state.newString,
+							incomingString = self.state.incomingString,
 						}),
 					}),
 				}),

plugin/src/App/StatusPages/Connected.lua

@@ -307,8 +307,8 @@ function ConnectedPage:init()
 		renderChanges = false,
 		hoveringChangeInfo = false,
 		showingStringDiff = false,
-		oldString = "",
+		currentString = "",
-		newString = "",
+		incomingString = "",
 	})
 
 	self.changeInfoText, self.setChangeInfoText = Roact.createBinding("")
@@ -511,11 +511,11 @@ function ConnectedPage:render()
 							patchData = self.props.patchData,
 							patchTree = self.props.patchTree,
 							serveSession = self.props.serveSession,
-							showStringDiff = function(oldString: string, newString: string)
+							showStringDiff = function(currentString: string, incomingString: string)
 								self:setState({
 									showingStringDiff = true,
-									oldString = oldString,
+									currentString = currentString,
-									newString = newString,
+									incomingString = incomingString,
 								})
 							end,
 							showTableDiff = function(oldTable: { [any]: any? }, newTable: { [any]: any? })
@@ -566,8 +566,8 @@ function ConnectedPage:render()
 							anchorPoint = Vector2.new(0, 0),
 							transparency = self.props.transparency,
 
-							oldString = self.state.oldString,
+							currentString = self.state.currentString,
-							newString = self.state.newString,
+							incomingString = self.state.incomingString,
 						}),
 					}),
 				}),

plugin/src/App/StatusPages/Connecting.lua

@@ -4,6 +4,8 @@ local Packages = Rojo.Packages
 
 local Roact = require(Packages.Roact)
 
+local Theme = require(Plugin.App.Theme)
+
 local Spinner = require(Plugin.App.Components.Spinner)
 
 local e = Roact.createElement
@@ -11,11 +13,35 @@ local e = Roact.createElement
 local ConnectingPage = Roact.Component:extend("ConnectingPage")
 
 function ConnectingPage:render()
-	return e(Spinner, {
+	return Theme.with(function(theme)
-		position = UDim2.new(0.5, 0, 0.5, 0),
+		return e("Frame", {
-		anchorPoint = Vector2.new(0.5, 0.5),
+			Size = UDim2.new(1, 0, 1, 0),
-		transparency = self.props.transparency,
+			BackgroundTransparency = 1,
-	})
+		}, {
+			Spinner = e(Spinner, {
+				position = UDim2.new(0.5, 0, 0.5, 0),
+				anchorPoint = Vector2.new(0.5, 0.5),
+				transparency = self.props.transparency,
+			}),
+			Text = if type(self.props.text) == "string" and #self.props.text > 0
+				then e("TextLabel", {
+					Text = self.props.text,
+					Position = UDim2.new(0.5, 0, 0.5, 30),
+					Size = UDim2.new(1, -40, 0.5, -40),
+					AnchorPoint = Vector2.new(0.5, 0),
+					TextXAlignment = Enum.TextXAlignment.Center,
+					TextYAlignment = Enum.TextYAlignment.Top,
+					RichText = true,
+					FontFace = theme.Font.Thin,
+					TextSize = theme.TextSize.Medium,
+					TextColor3 = theme.SubTextColor,
+					TextTruncate = Enum.TextTruncate.AtEnd,
+					TextTransparency = self.props.transparency,
+					BackgroundTransparency = 1,
+				})
+				else nil,
+		})
+	end)
 end
 
 return ConnectingPage

plugin/src/App/StatusPages/Error.lua

@@ -8,6 +8,7 @@ local Theme = require(Plugin.App.Theme)
 local getTextBoundsAsync = require(Plugin.App.getTextBoundsAsync)
 
 local TextButton = require(Plugin.App.Components.TextButton)
+local Header = require(Plugin.App.Components.Header)
 local BorderedContainer = require(Plugin.App.Components.BorderedContainer)
 local ScrollingFrame = require(Plugin.App.Components.ScrollingFrame)
 local Tooltip = require(Plugin.App.Components.Tooltip)
@@ -38,6 +39,7 @@ function Error:render()
 				return UDim2.new(1, 0, 0, math.min(outerSize.Y, maximumSize.Y))
 			end),
 			transparency = self.props.transparency,
+			layoutOrder = self.props.layoutOrder,
 		}, {
 			ScrollingFrame = e(ScrollingFrame, {
 				size = UDim2.new(1, 0, 1, 0),
@@ -108,16 +110,21 @@ function ErrorPage:render()
 			self.setContainerSize(object.AbsoluteSize)
 		end,
 	}, {
-		Error = e(Error, {
+		Header = e(Header, {
-			errorMessage = self.state.errorMessage,
-			containerSize = self.containerSize,
 			transparency = self.props.transparency,
 			layoutOrder = 1,
 		}),
 
+		Error = e(Error, {
+			errorMessage = self.state.errorMessage,
+			containerSize = self.containerSize,
+			transparency = self.props.transparency,
+			layoutOrder = 2,
+		}),
+
 		Buttons = e("Frame", {
 			Size = UDim2.new(1, 0, 0, 35),
-			LayoutOrder = 2,
+			LayoutOrder = 3,
 			BackgroundTransparency = 1,
 		}, {
 			Close = e(TextButton, {

plugin/src/App/StatusPages/Settings/init.lua

@@ -27,6 +27,7 @@ end
 
 local invertedLevels = invertTbl(Log.Level)
 local confirmationBehaviors = { "Initial", "Always", "Large Changes", "Unlisted PlaceId", "Never" }
+local syncReminderModes = { "None", "Notify", "Fullscreen" }
 
 local function Navbar(props)
 	return Theme.with(function(theme)
@@ -93,6 +94,14 @@ function SettingsPage:render()
 			contentSize = self.contentSize,
 			transparency = self.props.transparency,
 		}, {
+			AutoReconnect = e(Setting, {
+				id = "autoReconnect",
+				name = "Auto Reconnect",
+				description = "Reconnect to server on place open if the served project matches the last sync to the place",
+				transparency = self.props.transparency,
+				layoutOrder = layoutIncrement(),
+			}),
+
 			ShowNotifications = e(Setting, {
 				id = "showNotifications",
 				name = "Show Notifications",
@@ -101,13 +110,26 @@ function SettingsPage:render()
 				layoutOrder = layoutIncrement(),
 			}),
 
-			SyncReminder = e(Setting, {
+			SyncReminderMode = e(Setting, {
-				id = "syncReminder",
+				id = "syncReminderMode",
 				name = "Sync Reminder",
-				description = "Notify to sync when opening a place that has previously been synced",
+				description = "What type of reminders you receive for syncing your project",
 				transparency = self.props.transparency,
-				visible = Settings:getBinding("showNotifications"),
 				layoutOrder = layoutIncrement(),
+				visible = Settings:getBinding("showNotifications"),
+
+				options = syncReminderModes,
+			}),
+
+			SyncReminderPolling = e(Setting, {
+				id = "syncReminderPolling",
+				name = "Sync Reminder Polling",
+				description = "Look for available sync servers periodically",
+				transparency = self.props.transparency,
+				layoutOrder = layoutIncrement(),
+				visible = Settings:getBindings("syncReminderMode", "showNotifications"):map(function(values)
+					return values.syncReminderMode ~= "None" and values.showNotifications
+				end),
 			}),
 
 			ConfirmationBehavior = e(Setting, {
@@ -159,6 +181,14 @@ function SettingsPage:render()
 				layoutOrder = layoutIncrement(),
 			}),
 
+			EnableSyncFallback = e(Setting, {
+				id = "enableSyncFallback",
+				name = "Enable Sync Fallback",
+				description = "Whether Instances that fail to sync are remade as a fallback. If this is enabled, Instances may be destroyed and remade when syncing.",
+				transparency = self.props.transparency,
+				layoutOrder = layoutIncrement(),
+			}),
+
 			CheckForUpdates = e(Setting, {
 				id = "checkForUpdates",
 				name = "Check For Updates",

plugin/src/App/Theme.lua

@@ -165,12 +165,29 @@ function StudioProvider:updateTheme()
 			BackgroundColor = studioTheme:GetColor(Enum.StudioStyleGuideColor.InputFieldBackground),
 		},
 		Diff = {
-			-- Studio doesn't have good colors since their diffs use backgrounds, not text
+			-- Very bright different colors in case some places were not updated to use
-			Add = if isDark then Color3.fromRGB(143, 227, 154) else Color3.fromRGB(41, 164, 45),
+			-- the new background diff colors.
-			Remove = if isDark then Color3.fromRGB(242, 125, 125) else Color3.fromRGB(150, 29, 29),
+			Add = Color3.fromRGB(255, 0, 255),
-			Edit = if isDark then Color3.fromRGB(120, 154, 248) else Color3.fromRGB(0, 70, 160),
+			Remove = Color3.fromRGB(255, 0, 255),
+			Edit = Color3.fromRGB(255, 0, 255),
+
 			Row = studioTheme:GetColor(Enum.StudioStyleGuideColor.BrightText),
 			Warning = studioTheme:GetColor(Enum.StudioStyleGuideColor.WarningText),
+
+			Background = {
+				-- Studio doesn't have good colors since their diffs use backgrounds, not text
+				Add = if isDark then Color3.fromRGB(143, 227, 154) else Color3.fromRGB(41, 164, 45),
+				Remove = if isDark then Color3.fromRGB(242, 125, 125) else Color3.fromRGB(150, 29, 29),
+				Edit = if isDark then Color3.fromRGB(120, 154, 248) else Color3.fromRGB(0, 70, 160),
+				Remain = studioTheme:GetColor(Enum.StudioStyleGuideColor.BrightText),
+			},
+
+			Text = {
+				Add = if isDark then Color3.new(0, 0, 0) else Color3.new(1, 1, 1),
+				Remove = if isDark then Color3.new(0, 0, 0) else Color3.new(1, 1, 1),
+				Edit = if isDark then Color3.new(0, 0, 0) else Color3.new(1, 1, 1),
+				Remain = studioTheme:GetColor(Enum.StudioStyleGuideColor.MainText),
+			},
 		},
 		ConnectionDetails = {
 			ProjectNameColor = studioTheme:GetColor(Enum.StudioStyleGuideColor.BrightText),

plugin/src/App/bindingUtil.lua

@@ -44,7 +44,7 @@ end
 local function blendAlpha(alphaValues)
 	local alpha = 0
 
-	for _, value in pairs(alphaValues) do
+	for _, value in alphaValues do
 		alpha = alpha + (1 - alpha) * value
 	end
 

plugin/src/App/init.lua

@@ -9,6 +9,7 @@ local Packages = Rojo.Packages
 
 local Roact = require(Packages.Roact)
 local Log = require(Packages.Log)
+local Promise = require(Packages.Promise)
 
 local Assets = require(Plugin.Assets)
 local Version = require(Plugin.Version)
@@ -27,7 +28,7 @@ local timeUtil = require(Plugin.timeUtil)
 local Theme = require(script.Theme)
 
 local Page = require(script.Page)
-local Notifications = require(script.Notifications)
+local Notifications = require(script.Components.Notifications)
 local Tooltip = require(script.Components.Tooltip)
 local StudioPluginAction = require(script.Components.Studio.StudioPluginAction)
 local StudioToolbar = require(script.Components.Studio.StudioToolbar)
@@ -78,17 +79,18 @@ function App:init()
 				action
 			)
 		)
-		local dismissNotif = self:addNotification(
+		local dismissNotif = self:addNotification({
-			string.format("You've undone '%s'.\nIf this was not intended, please restore.", action),
+			text = string.format("You've undone '%s'.\nIf this was not intended, please restore.", action),
-			10,
+			timeout = 10,
-			{
+			onClose = function()
+				cleanup()
+			end,
+			actions = {
 				Restore = {
 					text = "Restore",
 					style = "Solid",
 					layoutOrder = 1,
-					onClick = function(notification)
+					onClick = function()
-						cleanup()
-						notification:dismiss()
 						ChangeHistoryService:Redo()
 					end,
 				},
@@ -96,13 +98,9 @@ function App:init()
 					text = "Dismiss",
 					style = "Bordered",
 					layoutOrder = 2,
-					onClick = function(notification)
-						cleanup()
-						notification:dismiss()
-					end,
 				},
-			}
+			},
-		)
+		})
 
 		undoConnection = ChangeHistoryService.OnUndo:Once(function()
 			-- Our notif is now out of date- redoing will not restore the patch
@@ -142,42 +140,20 @@ function App:init()
 	if RunService:IsEdit() then
 		self:checkForUpdates()
 
-		if
+		self:startSyncReminderPolling()
-			Settings:get("syncReminder")
+		self.disconnectSyncReminderPollingChanged = Settings:onChanged("syncReminderPolling", function(enabled)
-			and self.serveSession == nil
+			if enabled then
-			and self:getPriorSyncInfo().timestamp ~= nil
+				self:startSyncReminderPolling()
-			and (self:isSyncLockAvailable())
+			else
-		then
+				self:stopSyncReminderPolling()
-			local syncInfo = self:getPriorSyncInfo()
+			end
-			local timeSinceSync = timeUtil.elapsedToText(os.time() - syncInfo.timestamp)
+		end)
-			local syncDetail = if syncInfo.projectName
-				then `project '{syncInfo.projectName}'`
-				else `{syncInfo.host or Config.defaultHost}:{syncInfo.port or Config.defaultPort}`
 
-			self:addNotification(
+		self:tryAutoReconnect():andThen(function(didReconnect)
-				`You synced {syncDetail} to this place {timeSinceSync}. Would you like to reconnect?`,
+			if not didReconnect then
-				300,
+				self:checkSyncReminder()
-				{
+			end
-					Connect = {
+		end)
-						text = "Connect",
-						style = "Solid",
-						layoutOrder = 1,
-						onClick = function(notification)
-							notification:dismiss()
-							self:startSession()
-						end,
-					},
-					Dismiss = {
-						text = "Dismiss",
-						style = "Bordered",
-						layoutOrder = 2,
-						onClick = function(notification)
-							notification:dismiss()
-						end,
-					},
-				}
-			)
-		end
 	end
 
 	if self:isAutoConnectPlaytestServerAvailable() then
@@ -198,21 +174,30 @@ function App:init()
 end
 
 function App:willUnmount()
+	self:endSession()
+
 	self.waypointConnection:Disconnect()
 	self.confirmationBindable:Destroy()
 
 	self.disconnectUpdatesCheckChanged()
 	self.disconnectPrereleasesCheckChanged()
+	if self.disconnectSyncReminderPollingChanged then
+		self.disconnectSyncReminderPollingChanged()
+	end
+
+	self:stopSyncReminderPolling()
 
 	self.autoConnectPlaytestServerListener()
 	self:clearRunningConnectionInfo()
 end
 
-function App:addNotification(
+function App:addNotification(notif: {
 	text: string,
+	isFullscreen: boolean?,
 	timeout: number?,
-	actions: { [string]: { text: string, style: string, layoutOrder: number, onClick: (any) -> () } }?
+	actions: { [string]: { text: string, style: string, layoutOrder: number, onClick: (any) -> ()? } }?,
-)
+	onClose: (any) -> ()?,
+})
 	if not Settings:get("showNotifications") then
 		return
 	end
@@ -220,17 +205,17 @@ function App:addNotification(
 	self.notifId += 1
 	local id = self.notifId
 
-	local notifications = table.clone(self.state.notifications)
+	self:setState(function(prevState)
-	notifications[id] = {
+		local notifications = table.clone(prevState.notifications)
-		text = text,
+		notifications[id] = Dictionary.merge({
-		timestamp = DateTime.now().UnixTimestampMillis,
+			timeout = notif.timeout or 5,
-		timeout = timeout or 3,
+			isFullscreen = notif.isFullscreen or false,
-		actions = actions,
+		}, notif)
-	}
 
-	self:setState({
+		return {
-		notifications = notifications,
+			notifications = notifications,
-	})
+		}
+	end)
 
 	return function()
 		self:closeNotification(id)
@@ -242,46 +227,32 @@ function App:closeNotification(id: number)
 		return
 	end
 
-	local notifications = table.clone(self.state.notifications)
+	self:setState(function(prevState)
-	notifications[id] = nil
+		local notifications = table.clone(prevState.notifications)
+		notifications[id] = nil
 
-	self:setState({
+		return {
-		notifications = notifications,
+			notifications = notifications,
-	})
+		}
+	end)
 end
 
 function App:checkForUpdates()
-	if not Settings:get("checkForUpdates") then
+	local updateMessage = Version.getUpdateMessage()
-		return
-	end
 
-	local isLocalInstall = string.find(debug.traceback(), "\n[^\n]-user_.-$") ~= nil
+	if updateMessage then
-	local latestCompatibleVersion = Version.retrieveLatestCompatible({
+		self:addNotification({
-		version = Config.version,
+			text = updateMessage,
-		includePrereleases = isLocalInstall and Settings:get("checkForPrereleases"),
+			timeout = 500,
-	})
+			actions = {
-	if not latestCompatibleVersion then
+				Dismiss = {
-		return
+					text = "Dismiss",
-	end
+					style = "Bordered",
-
+					layoutOrder = 2,
-	self:addNotification(
+				},
-		string.format(
-			"A newer compatible version of Rojo, %s, was published %s! Go to the Rojo releases page to learn more.",
-			Version.display(latestCompatibleVersion.version),
-			timeUtil.elapsedToText(DateTime.now().UnixTimestamp - latestCompatibleVersion.publishedUnixTimestamp)
-		),
-		500,
-		{
-			Dismiss = {
-				text = "Dismiss",
-				style = "Bordered",
-				layoutOrder = 2,
-				onClick = function(notification)
-					notification:dismiss()
-				end,
 			},
-		}
+		})
-	)
+	end
 end
 
 function App:getPriorSyncInfo(): { host: string?, port: string?, projectName: string?, timestamp: number? }
@@ -402,8 +373,158 @@ function App:releaseSyncLock()
 	Log.trace("Could not relase sync lock because it is owned by {}", lock.Value)
 end
 
+function App:findActiveServer()
+	local host, port = self:getHostAndPort()
+	local baseUrl = if string.find(host, "^https?://")
+		then string.format("%s:%s", host, port)
+		else string.format("http://%s:%s", host, port)
+
+	Log.trace("Checking for active sync server at {}", baseUrl)
+
+	local apiContext = ApiContext.new(baseUrl)
+	return apiContext:connect():andThen(function(serverInfo)
+		apiContext:disconnect()
+		return serverInfo, host, port
+	end)
+end
+
+function App:tryAutoReconnect()
+	if not Settings:get("autoReconnect") then
+		return Promise.resolve(false)
+	end
+
+	local priorSyncInfo = self:getPriorSyncInfo()
+	if not priorSyncInfo.projectName then
+		Log.trace("No prior sync info found, skipping auto-reconnect")
+		return Promise.resolve(false)
+	end
+
+	return self:findActiveServer()
+		:andThen(function(serverInfo)
+			-- change
+			if serverInfo.projectName == priorSyncInfo.projectName then
+				Log.trace("Auto-reconnect found matching server, reconnecting...")
+				self:addNotification({
+					text = `Auto-reconnect discovered project '{serverInfo.projectName}'...`,
+				})
+				self:startSession()
+				return true
+			end
+			Log.trace("Auto-reconnect found different server, not reconnecting")
+			return false
+		end)
+		:catch(function()
+			Log.trace("Auto-reconnect did not find a server, not reconnecting")
+			return false
+		end)
+end
+
+function App:checkSyncReminder()
+	local syncReminderMode = Settings:get("syncReminderMode")
+	if syncReminderMode == "None" then
+		return
+	end
+
+	if self.serveSession ~= nil or not self:isSyncLockAvailable() then
+		-- Already syncing or cannot sync, no reason to remind
+		return
+	end
+
+	local priorSyncInfo = self:getPriorSyncInfo()
+
+	self:findActiveServer()
+		:andThen(function(serverInfo, host, port)
+			self:sendSyncReminder(
+				`Project '{serverInfo.projectName}' is serving at {host}:{port}.\nWould you like to connect?`
+			)
+		end)
+		:catch(function()
+			if priorSyncInfo.timestamp and priorSyncInfo.projectName then
+				-- We didn't find an active server,
+				-- but this place has a prior sync
+				-- so we should remind the user to serve
+
+				local timeSinceSync = timeUtil.elapsedToText(os.time() - priorSyncInfo.timestamp)
+				self:sendSyncReminder(
+					`You synced project '{priorSyncInfo.projectName}' to this place {timeSinceSync}.\nDid you mean to run 'rojo serve' and then connect?`
+				)
+			end
+		end)
+end
+
+function App:startSyncReminderPolling()
+	if
+		self.syncReminderPollingThread ~= nil
+		or Settings:get("syncReminderMode") == "None"
+		or not Settings:get("syncReminderPolling")
+	then
+		return
+	end
+
+	Log.trace("Starting sync reminder polling thread")
+	self.syncReminderPollingThread = task.spawn(function()
+		while task.wait(30) do
+			if self.syncReminderPollingThread == nil then
+				-- The polling thread was stopped, so exit
+				return
+			end
+			if self.dismissSyncReminder then
+				-- There is already a sync reminder being shown
+				task.wait(5)
+				continue
+			end
+			self:checkSyncReminder()
+		end
+	end)
+end
+
+function App:stopSyncReminderPolling()
+	if self.syncReminderPollingThread then
+		Log.trace("Stopping sync reminder polling thread")
+		task.cancel(self.syncReminderPollingThread)
+		self.syncReminderPollingThread = nil
+	end
+end
+
+function App:sendSyncReminder(message: string)
+	local syncReminderMode = Settings:get("syncReminderMode")
+	if syncReminderMode == "None" then
+		return
+	end
+
+	self.dismissSyncReminder = self:addNotification({
+		text = message,
+		timeout = 120,
+		isFullscreen = Settings:get("syncReminderMode") == "Fullscreen",
+		onClose = function()
+			self.dismissSyncReminder = nil
+		end,
+		actions = {
+			Connect = {
+				text = "Connect",
+				style = "Solid",
+				layoutOrder = 1,
+				onClick = function()
+					self:startSession()
+				end,
+			},
+			Dismiss = {
+				text = "Dismiss",
+				style = "Bordered",
+				layoutOrder = 2,
+				onClick = function()
+					-- If the user dismisses the reminder,
+					-- then we don't need to remind them again
+					self:stopSyncReminderPolling()
+				end,
+			},
+		},
+	})
+end
+
 function App:isAutoConnectPlaytestServerAvailable()
-	return RunService:IsRunMode()
+	return RunService:IsRunning()
+		and RunService:IsStudio()
 		and RunService:IsServer()
 		and Settings:get("autoConnectPlaytestServer")
 		and workspace:GetAttribute("__Rojo_ConnectionUrl")
@@ -451,7 +572,10 @@ function App:startSession()
 		local msg = string.format("Could not sync because user '%s' is already syncing", tostring(priorOwner))
 
 		Log.warn(msg)
-		self:addNotification(msg, 10)
+		self:addNotification({
+			text = msg,
+			timeout = 10,
+		})
 		self:setState({
 			appStatus = AppStatus.Error,
 			errorMessage = msg,
@@ -473,60 +597,59 @@ function App:startSession()
 		twoWaySync = Settings:get("twoWaySync"),
 	})
 
-	self.cleanupPrecommit = serveSession.__reconciler:hookPrecommit(function(patch, instanceMap)
+	serveSession:setUpdateLoadingTextCallback(function(text: string)
+		self:setState({
+			connectingText = text,
+		})
+	end)
+
+	self.cleanupPrecommit = serveSession:hookPrecommit(function(patch, instanceMap)
 		-- Build new tree for patch
 		self:setState({
 			patchTree = PatchTree.build(patch, instanceMap, { "Property", "Old", "New" }),
 		})
 	end)
-	self.cleanupPostcommit = serveSession.__reconciler:hookPostcommit(function(patch, instanceMap, unappliedPatch)
+	self.cleanupPostcommit = serveSession:hookPostcommit(function(patch, instanceMap, unappliedPatch)
-		-- Update tree with unapplied metadata
+		local now = DateTime.now().UnixTimestamp
 		self:setState(function(prevState)
+			local oldPatchData = prevState.patchData
+			local newPatchData = {
+				patch = patch,
+				unapplied = unappliedPatch,
+				timestamp = now,
+			}
+
+			if PatchSet.isEmpty(patch) then
+				-- Keep existing patch info, but use new timestamp
+				newPatchData.patch = oldPatchData.patch
+				newPatchData.unapplied = oldPatchData.unapplied
+			elseif now - oldPatchData.timestamp < 2 then
+				-- Patches that apply in the same second are combined for human clarity
+				newPatchData.patch = PatchSet.assign(PatchSet.newEmpty(), oldPatchData.patch, patch)
+				newPatchData.unapplied = PatchSet.assign(PatchSet.newEmpty(), oldPatchData.unapplied, unappliedPatch)
+			end
+
 			return {
 				patchTree = PatchTree.updateMetadata(prevState.patchTree, patch, instanceMap, unappliedPatch),
+				patchData = newPatchData,
 			}
 		end)
 	end)
 
-	serveSession:hookPostcommit(function(patch, _instanceMap, unapplied)
-		local now = DateTime.now().UnixTimestamp
-		local old = self.state.patchData
-
-		if PatchSet.isEmpty(patch) then
-			-- Ignore empty patch, but update timestamp
-			self:setState({
-				patchData = {
-					patch = old.patch,
-					unapplied = old.unapplied,
-					timestamp = now,
-				},
-			})
-			return
-		end
-
-		if now - old.timestamp < 2 then
-			-- Patches that apply in the same second are
-			-- considered to be part of the same change for human clarity
-			patch = PatchSet.assign(PatchSet.newEmpty(), old.patch, patch)
-			unapplied = PatchSet.assign(PatchSet.newEmpty(), old.unapplied, unapplied)
-		end
-
-		self:setState({
-			patchData = {
-				patch = patch,
-				unapplied = unapplied,
-				timestamp = now,
-			},
-		})
-	end)
-
 	serveSession:onStatusChanged(function(status, details)
 		if status == ServeSession.Status.Connecting then
+			if self.dismissSyncReminder then
+				self.dismissSyncReminder()
+				self.dismissSyncReminder = nil
+			end
+
 			self:setState({
 				appStatus = AppStatus.Connecting,
 				toolbarIcon = Assets.Images.PluginButton,
 			})
-			self:addNotification("Connecting to session...")
+			self:addNotification({
+				text = "Connecting to session...",
+			})
 		elseif status == ServeSession.Status.Connected then
 			self.knownProjects[details] = true
 			self:setPriorSyncInfo(host, port, details)
@@ -539,7 +662,9 @@ function App:startSession()
 				address = address,
 				toolbarIcon = Assets.Images.PluginButtonConnected,
 			})
-			self:addNotification(string.format("Connected to session '%s' at %s.", details, address), 5)
+			self:addNotification({
+				text = string.format("Connected to session '%s' at %s.", details, address),
+			})
 		elseif status == ServeSession.Status.Disconnected then
 			self.serveSession = nil
 			self:releaseSyncLock()
@@ -562,13 +687,19 @@ function App:startSession()
 					errorMessage = tostring(details),
 					toolbarIcon = Assets.Images.PluginButtonWarning,
 				})
-				self:addNotification(tostring(details), 10)
+				self:addNotification({
+					text = tostring(details),
+					timeout = 10,
+				})
 			else
 				self:setState({
 					appStatus = AppStatus.NotConnected,
 					toolbarIcon = Assets.Images.PluginButton,
 				})
-				self:addNotification("Disconnected from session.")
+				self:addNotification({
+					text = "Disconnected from session.",
+					timeout = 10,
+				})
 			end
 		end
 	end)
@@ -636,23 +767,25 @@ function App:startSession()
 			end
 		end
 
+		self:setState({
+			connectingText = "Computing diff view...",
+		})
 		self:setState({
 			appStatus = AppStatus.Confirming,
+			patchTree = PatchTree.build(patch, instanceMap, { "Property", "Current", "Incoming" }),
 			confirmData = {
-				instanceMap = instanceMap,
-				patch = patch,
 				serverInfo = serverInfo,
 			},
 			toolbarIcon = Assets.Images.PluginButton,
 		})
 
-		self:addNotification(
+		self:addNotification({
-			string.format(
+			text = string.format(
 				"Please accept%sor abort the initializing sync session.",
 				Settings:get("twoWaySync") and ", reject, " or " "
 			),
-			7
+			timeout = 7,
-		)
+		})
 
 		return self.confirmationEvent:Wait()
 	end)
@@ -751,6 +884,7 @@ function App:render()
 
 					ConfirmingPage = createPageElement(AppStatus.Confirming, {
 						confirmData = self.state.confirmData,
+						patchTree = self.state.patchTree,
 						createPopup = not self.state.guiEnabled,
 
 						onAbort = function()
@@ -764,7 +898,9 @@ function App:render()
 						end,
 					}),
 
-					Connecting = createPageElement(AppStatus.Connecting),
+					Connecting = createPageElement(AppStatus.Connecting, {
+						text = self.state.connectingText,
+					}),
 
 					Connected = createPageElement(AppStatus.Connected, {
 						projectName = self.state.projectName,
@@ -813,19 +949,7 @@ function App:render()
 					ResetOnSpawn = false,
 					DisplayOrder = 100,
 				}, {
-					layout = e("UIListLayout", {
+					Notifications = e(Notifications, {
-						SortOrder = Enum.SortOrder.LayoutOrder,
-						HorizontalAlignment = Enum.HorizontalAlignment.Right,
-						VerticalAlignment = Enum.VerticalAlignment.Bottom,
-						Padding = UDim.new(0, 5),
-					}),
-					padding = e("UIPadding", {
-						PaddingTop = UDim.new(0, 5),
-						PaddingBottom = UDim.new(0, 5),
-						PaddingLeft = UDim.new(0, 5),
-						PaddingRight = UDim.new(0, 5),
-					}),
-					notifs = e(Notifications, {
 						soundPlayer = self.props.soundPlayer,
 						notifications = self.state.notifications,
 						onClose = function(id)

plugin/src/Assets.lua

@@ -74,7 +74,7 @@ local Assets = {
 local function guardForTypos(name, map)
 	strict(name, map)
 
-	for key, child in pairs(map) do
+	for key, child in map do
 		if type(child) == "table" then
 			guardForTypos(("%s.%s"):format(name, key), child)
 		end

plugin/src/ChangeBatcher/createPatchSet.lua

@@ -15,7 +15,7 @@ local encodePatchUpdate = require(script.Parent.encodePatchUpdate)
 return function(instanceMap, propertyChanges)
 	local patch = PatchSet.newEmpty()
 
-	for instance, properties in pairs(propertyChanges) do
+	for instance, properties in propertyChanges do
 		local instanceId = instanceMap.fromInstances[instance]
 
 		if instanceId == nil then

plugin/src/ChangeBatcher/encodePatchUpdate.lua

@@ -10,7 +10,7 @@ return function(instance, instanceId, properties)
 		changedProperties = {},
 	}
 
-	for propertyName in pairs(properties) do
+	for propertyName in properties do
 		if propertyName == "Name" then
 			update.changedName = instance.Name
 		else

plugin/src/Config.lua

@@ -21,7 +21,7 @@ return strict("Config", {
 	codename = "Epiphany",
 	version = realVersion,
 	expectedServerVersionString = ("%d.%d or newer"):format(realVersion[1], realVersion[2]),
-	protocolVersion = 4,
+	protocolVersion = 5,
 	defaultHost = "localhost",
 	defaultPort = "34872",
 })

plugin/src/Dictionary.lua

@@ -14,7 +14,7 @@ local function merge(...)
 		local source = select(i, ...)
 
 		if source ~= nil then
-			for key, value in pairs(source) do
+			for key, value in source do
 				if value == None then
 					output[key] = nil
 				else

plugin/src/InstanceMap.lua

@@ -63,7 +63,7 @@ function InstanceMap:__fmtDebug(output)
 	-- 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
+	for id, instance in self.fromIds do
 		local label = string.format("%s (%s)", instance:GetFullName(), instance.ClassName)
 
 		table.insert(entries, { id, label })
@@ -73,7 +73,7 @@ function InstanceMap:__fmtDebug(output)
 		return a[2] < b[2]
 	end)
 
-	for _, entry in ipairs(entries) do
+	for _, entry in entries do
 		output:writeLine("{}: {}", entry[1], entry[2])
 	end
 
@@ -227,7 +227,7 @@ function InstanceMap:__disconnectSignals(instance)
 		-- 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
+			for _, signal in signals do
 				signal:Disconnect()
 			end
 		else

plugin/src/PatchSet.lua

@@ -282,6 +282,22 @@ function PatchSet.assign(target, ...)
 	return target
 end
 
+function PatchSet.addedIdList(patchSet): { string }
+	local idList = table.create(#patchSet.added)
+	for id in patchSet.added do
+		table.insert(idList, id)
+	end
+	return table.freeze(idList)
+end
+
+function PatchSet.updatedIdList(patchSet): { string }
+	local idList = table.create(#patchSet.updated)
+	for _, item in patchSet.updated do
+		table.insert(idList, item.id)
+	end
+	return table.freeze(idList)
+end
+
 --[[
 	Create a list of human-readable statements summarizing the contents of this
 	patch, intended to be displayed to users.

plugin/src/PatchTree.lua

@@ -16,6 +16,14 @@ local Types = require(Plugin.Types)
 local decodeValue = require(Plugin.Reconciler.decodeValue)
 local getProperty = require(Plugin.Reconciler.getProperty)
 
+local function yieldIfNeeded(clock)
+	if os.clock() - clock > 1 / 20 then
+		task.wait()
+		return os.clock()
+	end
+	return clock
+end
+
 local function alphabeticalNext(t, state)
 	-- Equivalent of the next function, but returns the keys in the alphabetic
 	-- order of node names. We use a temporary ordered key table that is stored in the
@@ -132,7 +140,6 @@ end
 -- props must contain id, and cannot contain children or parentId
 -- other than those three, it can hold anything
 function Tree:addNode(parent, props)
-	Timer.start("Tree:addNode")
 	assert(props.id, "props must contain id")
 
 	parent = parent or "ROOT"
@@ -143,7 +150,6 @@ function Tree:addNode(parent, props)
 		for k, v in props do
 			node[k] = v
 		end
-		Timer.stop()
 		return node
 	end
 
@@ -154,25 +160,25 @@ function Tree:addNode(parent, props)
 	local parentNode = self:getNode(parent)
 	if not parentNode then
 		Log.warn("Failed to create node since parent doesnt exist: {}, {}", parent, props)
-		Timer.stop()
 		return
 	end
 
 	parentNode.children[node.id] = node
 	self.idToNode[node.id] = node
 
-	Timer.stop()
 	return node
 end
 
 -- Given a list of ancestor ids in descending order, builds the nodes for them
 -- using the patch and instanceMap info
 function Tree:buildAncestryNodes(previousId: string?, ancestryIds: { string }, patch, instanceMap)
-	Timer.start("Tree:buildAncestryNodes")
+	local clock = os.clock()
 	-- Build nodes for ancestry by going up the tree
 	previousId = previousId or "ROOT"
 
 	for _, ancestorId in ancestryIds do
+		clock = yieldIfNeeded(clock)
+
 		local value = instanceMap.fromIds[ancestorId] or patch.added[ancestorId]
 		if not value then
 			Log.warn("Failed to find ancestor object for " .. ancestorId)
@@ -186,8 +192,6 @@ function Tree:buildAncestryNodes(previousId: string?, ancestryIds: { string }, p
 		})
 		previousId = ancestorId
 	end
-
-	Timer.stop()
 end
 
 local PatchTree = {}
@@ -196,12 +200,16 @@ local PatchTree = {}
 -- uses changeListHeaders in node.changeList
 function PatchTree.build(patch, instanceMap, changeListHeaders)
 	Timer.start("PatchTree.build")
+	local clock = os.clock()
+
 	local tree = Tree.new()
 
 	local knownAncestors = {}
 
 	Timer.start("patch.updated")
 	for _, change in patch.updated do
+		clock = yieldIfNeeded(clock)
+
 		local instance = instanceMap.fromIds[change.id]
 		if not instance then
 			continue
@@ -281,6 +289,8 @@ function PatchTree.build(patch, instanceMap, changeListHeaders)
 
 	Timer.start("patch.removed")
 	for _, idOrInstance in patch.removed do
+		clock = yieldIfNeeded(clock)
+
 		local instance = if Types.RbxId(idOrInstance) then instanceMap.fromIds[idOrInstance] else idOrInstance
 		if not instance then
 			-- If we're viewing a past patch, the instance is already removed
@@ -325,6 +335,8 @@ function PatchTree.build(patch, instanceMap, changeListHeaders)
 
 	Timer.start("patch.added")
 	for id, change in patch.added do
+		clock = yieldIfNeeded(clock)
+
 		-- Gather ancestors from existing DOM or future additions
 		local ancestryIds = {}
 		local parentId = change.Parent

plugin/src/Reconciler/applyPatch.lua

@@ -5,8 +5,6 @@
 	Patches can come from the server or be generated by the client.
 ]]
 
-local ChangeHistoryService = game:GetService("ChangeHistoryService")
-
 local Packages = script.Parent.Parent.Parent.Packages
 local Log = require(Packages.Log)
 
@@ -20,13 +18,6 @@ local reifyInstance, applyDeferredRefs = reify.reifyInstance, reify.applyDeferre
 local setProperty = require(script.Parent.setProperty)
 
 local function applyPatch(instanceMap, patch)
-	local patchTimestamp = DateTime.now():FormatLocalTime("LTS", "en-us")
-	local historyRecording = ChangeHistoryService:TryBeginRecording("Rojo: Patch " .. patchTimestamp)
-	if not historyRecording then
-		-- There can only be one recording at a time
-		Log.debug("Failed to begin history recording for " .. patchTimestamp .. ". Another recording is in progress.")
-	end
-
 	-- Tracks any portions of the patch that could not be applied to the DOM.
 	local unappliedPatch = PatchSet.newEmpty()
 
@@ -73,9 +64,6 @@ local function applyPatch(instanceMap, patch)
 		if parentInstance == nil then
 			-- This would be peculiar. If you create an instance with no
 			-- parent, were you supposed to create it at all?
-			if historyRecording then
-				ChangeHistoryService:FinishRecording(historyRecording, Enum.FinishRecordingOperation.Commit)
-			end
 			invariant(
 				"Cannot add an instance from a patch that has no parent.\nInstance {} with parent {}.\nState: {:#?}",
 				id,
@@ -244,10 +232,6 @@ local function applyPatch(instanceMap, patch)
 		end
 	end
 
-	if historyRecording then
-		ChangeHistoryService:FinishRecording(historyRecording, Enum.FinishRecordingOperation.Commit)
-	end
-
 	applyDeferredRefs(instanceMap, deferredRefs, unappliedPatch)
 
 	return unappliedPatch

plugin/src/Reconciler/diff.lua

@@ -25,18 +25,26 @@ local function trueEquals(a, b): boolean
 		return true
 	end
 
+	-- Treat nil and { Ref = "000...0" } as equal
+	if
+		(a == nil and type(b) == "table" and b.Ref == "00000000000000000000000000000000")
+		or (b == nil and type(a) == "table" and a.Ref == "00000000000000000000000000000000")
+	then
+		return true
+	end
+
 	local typeA, typeB = typeof(a), typeof(b)
 
 	-- For tables, try recursive deep equality
 	if typeA == "table" and typeB == "table" then
 		local checkedKeys = {}
-		for key, value in pairs(a) do
+		for key, value in a do
 			checkedKeys[key] = true
 			if not trueEquals(value, b[key]) then
 				return false
 			end
 		end
-		for key, value in pairs(b) do
+		for key, value in b do
 			if checkedKeys[key] then
 				continue
 			end

plugin/src/Reconciler/diff.spec.lua

@@ -14,7 +14,7 @@ return function()
 	local function size(dict)
 		local len = 0
 
-		for _ in pairs(dict) do
+		for _ in dict do
 			len = len + 1
 		end
 

plugin/src/Reconciler/hydrate.lua

@@ -26,7 +26,7 @@ local function hydrate(instanceMap, virtualInstances, rootId, rootInstance)
 	for _, childId in ipairs(virtualInstance.Children) do
 		local virtualChild = virtualInstances[childId]
 
-		for childIndex, childInstance in ipairs(existingChildren) do
+		for childIndex, childInstance in 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

plugin/src/Reconciler/init.lua

@@ -5,9 +5,6 @@
 
 local Rojo = script:FindFirstAncestor("Rojo")
 local Plugin = Rojo.Plugin
-local Packages = Rojo.Packages
-
-local Log = require(Packages.Log)
 
 local Timer = require(Plugin.Timer)
 
@@ -22,78 +19,17 @@ function Reconciler.new(instanceMap)
 	local self = {
 		-- Tracks all of the instances known by the reconciler by ID.
 		__instanceMap = instanceMap,
-		__precommitCallbacks = {},
-		__postcommitCallbacks = {},
 	}
 
 	return setmetatable(self, Reconciler)
 end
 
-function Reconciler:hookPrecommit(callback: (patch: any, instanceMap: any) -> ()): () -> ()
-	table.insert(self.__precommitCallbacks, callback)
-	Log.trace("Added precommit callback: {}", callback)
-
-	return function()
-		-- Remove the callback from the list
-		for i, cb in self.__precommitCallbacks do
-			if cb == callback then
-				table.remove(self.__precommitCallbacks, i)
-				Log.trace("Removed precommit callback: {}", callback)
-				break
-			end
-		end
-	end
-end
-
-function Reconciler:hookPostcommit(callback: (patch: any, instanceMap: any, unappliedPatch: any) -> ()): () -> ()
-	table.insert(self.__postcommitCallbacks, callback)
-	Log.trace("Added postcommit callback: {}", callback)
-
-	return function()
-		-- Remove the callback from the list
-		for i, cb in self.__postcommitCallbacks do
-			if cb == callback then
-				table.remove(self.__postcommitCallbacks, i)
-				Log.trace("Removed postcommit callback: {}", callback)
-				break
-			end
-		end
-	end
-end
-
 function Reconciler:applyPatch(patch)
 	Timer.start("Reconciler:applyPatch")
 
-	Timer.start("precommitCallbacks")
-	-- Precommit callbacks must be serial in order to obey the contract that
-	-- they execute before commit
-	for _, callback in self.__precommitCallbacks do
-		local success, err = pcall(callback, patch, self.__instanceMap)
-		if not success then
-			Log.warn("Precommit hook errored: {}", err)
-		end
-	end
-	Timer.stop()
-
-	Timer.start("apply")
 	local unappliedPatch = applyPatch(self.__instanceMap, patch)
-	Timer.stop()
-
-	Timer.start("postcommitCallbacks")
-	-- Postcommit callbacks can be called with spawn since regardless of firing order, they are
-	-- guaranteed to be called after the commit
-	for _, callback in self.__postcommitCallbacks do
-		task.spawn(function()
-			local success, err = pcall(callback, patch, self.__instanceMap, unappliedPatch)
-			if not success then
-				Log.warn("Postcommit hook errored: {}", err)
-			end
-		end)
-	end
-	Timer.stop()
 
 	Timer.stop()
-
 	return unappliedPatch
 end
 

plugin/src/Reconciler/reify.lua

@@ -126,7 +126,7 @@ function applyDeferredRefs(instanceMap, deferredRefs, unappliedPatch)
 		})
 	end
 
-	for _, entry in ipairs(deferredRefs) do
+	for _, entry in deferredRefs do
 		local _, refId = next(entry.virtualValue)
 
 		if refId == nil then

plugin/src/Reconciler/reify.spec.lua

@@ -12,7 +12,7 @@ return function()
 	local function size(dict)
 		local len = 0
 
-		for _ in pairs(dict) do
+		for _ in dict do
 			len = len + 1
 		end
 

plugin/src/ServeSession.lua

@@ -1,11 +1,15 @@
 local StudioService = game:GetService("StudioService")
 local RunService = game:GetService("RunService")
+local ChangeHistoryService = game:GetService("ChangeHistoryService")
+local SerializationService = game:GetService("SerializationService")
+local Selection = game:GetService("Selection")
 
 local Packages = script.Parent.Parent.Packages
 local Log = require(Packages.Log)
 local Fmt = require(Packages.Fmt)
 local t = require(Packages.t)
 local Promise = require(Packages.Promise)
+local Timer = require(script.Parent.Timer)
 
 local ChangeBatcher = require(script.Parent.ChangeBatcher)
 local encodePatchUpdate = require(script.Parent.ChangeBatcher.encodePatchUpdate)
@@ -44,6 +48,12 @@ local function debugPatch(object)
 	end)
 end
 
+local function attemptReparent(instance, parent)
+	return pcall(function()
+		instance.Parent = parent
+	end)
+end
+
 local ServeSession = {}
 ServeSession.__index = ServeSession
 
@@ -95,6 +105,9 @@ function ServeSession.new(options)
 		__changeBatcher = changeBatcher,
 		__statusChangedCallback = nil,
 		__connections = connections,
+		__precommitCallbacks = {},
+		__postcommitCallbacks = {},
+		__updateLoadingText = function() end,
 	}
 
 	setmetatable(self, ServeSession)
@@ -125,26 +138,83 @@ function ServeSession:setConfirmCallback(callback)
 	self.__userConfirmCallback = callback
 end
 
-function ServeSession:hookPrecommit(callback)
+function ServeSession:setUpdateLoadingTextCallback(callback)
-	return self.__reconciler:hookPrecommit(callback)
+	self.__updateLoadingText = callback
 end
 
+function ServeSession:setLoadingText(text: string)
+	self.__updateLoadingText(text)
+end
+
+--[=[
+	Hooks a function to run before patch application.
+	The provided function is called with the incoming patch and an InstanceMap
+	as parameters.
+]=]
+function ServeSession:hookPrecommit(callback)
+	table.insert(self.__precommitCallbacks, callback)
+	Log.trace("Added precommit callback: {}", callback)
+
+	return function()
+		-- Remove the callback from the list
+		for i, cb in self.__precommitCallbacks do
+			if cb == callback then
+				table.remove(self.__precommitCallbacks, i)
+				Log.trace("Removed precommit callback: {}", callback)
+				break
+			end
+		end
+	end
+end
+
+--[=[
+	Hooks a function to run after patch application.
+	The provided function is called with the applied patch, the current
+	InstanceMap, and a PatchSet containing any unapplied changes.
+]=]
 function ServeSession:hookPostcommit(callback)
-	return self.__reconciler:hookPostcommit(callback)
+	table.insert(self.__postcommitCallbacks, callback)
+	Log.trace("Added postcommit callback: {}", callback)
+
+	return function()
+		-- Remove the callback from the list
+		for i, cb in self.__postcommitCallbacks do
+			if cb == callback then
+				table.remove(self.__postcommitCallbacks, i)
+				Log.trace("Removed postcommit callback: {}", callback)
+				break
+			end
+		end
+	end
 end
 
 function ServeSession:start()
 	self:__setStatus(Status.Connecting)
+	self:setLoadingText("Connecting to server...")
 
 	self.__apiContext
 		:connect()
 		:andThen(function(serverInfo)
-			self:__applyGameAndPlaceId(serverInfo)
+			self:setLoadingText("Loading initial data from server...")
-
 			return self:__initialSync(serverInfo):andThen(function()
+				self:setLoadingText("Starting sync loop...")
 				self:__setStatus(Status.Connected, serverInfo.projectName)
+				self:__applyGameAndPlaceId(serverInfo)
 
-				return self:__mainSyncLoop()
+				return self.__apiContext:connectWebSocket({
+					["messages"] = function(messagesPacket)
+						if self.__status == Status.Disconnected then
+							return
+						end
+
+						Log.debug("Received {} messages from Rojo server", #messagesPacket.messages)
+
+						for _, message in messagesPacket.messages do
+							self:__applyPatch(message)
+						end
+						self.__apiContext:setMessageCursor(messagesPacket.messageCursor)
+					end,
+				})
 			end)
 		end)
 		:catch(function(err)
@@ -207,6 +277,194 @@ function ServeSession:__onActiveScriptChanged(activeScript)
 	self.__apiContext:open(scriptId)
 end
 
+function ServeSession:__replaceInstances(idList)
+	if #idList == 0 then
+		return true, PatchSet.newEmpty()
+	end
+	-- It would be annoying if selection went away, so we try to preserve it.
+	local selection = Selection:Get()
+	local selectionMap = {}
+	for i, instance in selection do
+		selectionMap[instance] = i
+	end
+
+	-- TODO: Should we do this in multiple requests so we can more granularly mark failures?
+	local modelSuccess, replacements = self.__apiContext
+		:serialize(idList)
+		:andThen(function(response)
+			Log.debug("Deserializing results from serialize endpoint")
+			local objects = SerializationService:DeserializeInstancesAsync(response.modelContents)
+			if not objects[1] then
+				return Promise.reject("Serialize endpoint did not deserialize into any Instances")
+			end
+			if #objects[1]:GetChildren() ~= #idList then
+				return Promise.reject("Serialize endpoint did not return the correct number of Instances")
+			end
+
+			local instanceMap = {}
+			for _, item in objects[1]:GetChildren() do
+				instanceMap[item.Name] = item.Value
+			end
+			return instanceMap
+		end)
+		:await()
+
+	local refSuccess, refPatch = self.__apiContext
+		:refPatch(idList)
+		:andThen(function(response)
+			return response.patch
+		end)
+		:await()
+
+	if not (modelSuccess and refSuccess) then
+		return false
+	end
+
+	for id, replacement in replacements do
+		local oldInstance = self.__instanceMap.fromIds[id]
+		if not oldInstance then
+			-- TODO: Why would this happen?
+			Log.warn("Instance {} not found in InstanceMap during sync replacement", id)
+			continue
+		end
+
+		self.__instanceMap:insert(id, replacement)
+		Log.trace("Swapping Instance {} out via api/models/ endpoint", id)
+		local oldParent = oldInstance.Parent
+		for _, child in oldInstance:GetChildren() do
+			-- Some children cannot be reparented, such as a TouchTransmitter
+			local reparentSuccess, reparentError = attemptReparent(child, replacement)
+			if not reparentSuccess then
+				Log.warn(
+					"Could not reparent child {} of instance {} during sync replacement: {}",
+					child.Name,
+					oldInstance.Name,
+					reparentError
+				)
+			end
+		end
+
+		-- ChangeHistoryService doesn't like it if an Instance has been
+		-- Destroyed. So, we have to accept the potential memory hit and
+		-- just set the parent to `nil`.
+		local deleteSuccess, deleteError = attemptReparent(oldInstance, nil)
+		local replaceSuccess, replaceError = attemptReparent(replacement, oldParent)
+
+		if not (deleteSuccess and replaceSuccess) then
+			Log.warn(
+				"Could not swap instances {} and {} during sync replacement: {}",
+				oldInstance.Name,
+				replacement.Name,
+				(deleteError or "") .. "\n" .. (replaceError or "")
+			)
+
+			-- We need to revert the failed swap to avoid losing the old instance and children.
+			for _, child in replacement:GetChildren() do
+				attemptReparent(child, oldInstance)
+			end
+			attemptReparent(oldInstance, oldParent)
+
+			-- Our replacement should never have existed in the first place, so we can just destroy it.
+			replacement:Destroy()
+			continue
+		end
+
+		if selectionMap[oldInstance] then
+			-- This is a bit funky, but it saves the order of Selection
+			-- which might matter for some use cases.
+			selection[selectionMap[oldInstance]] = replacement
+		end
+	end
+
+	local patchApplySuccess, unappliedPatch = pcall(self.__reconciler.applyPatch, self.__reconciler, refPatch)
+	if patchApplySuccess then
+		Selection:Set(selection)
+		return true, unappliedPatch
+	else
+		error(unappliedPatch)
+	end
+end
+
+function ServeSession:__applyPatch(patch)
+	local patchTimestamp = DateTime.now():FormatLocalTime("LTS", "en-us")
+	local historyRecording = ChangeHistoryService:TryBeginRecording("Rojo: Patch " .. patchTimestamp)
+	if not historyRecording then
+		-- There can only be one recording at a time
+		Log.debug("Failed to begin history recording for " .. patchTimestamp .. ". Another recording is in progress.")
+	end
+
+	Timer.start("precommitCallbacks")
+	-- Precommit callbacks must be serial in order to obey the contract that
+	-- they execute before commit
+	for _, callback in self.__precommitCallbacks do
+		local success, err = pcall(callback, patch, self.__instanceMap)
+		if not success then
+			Log.warn("Precommit hook errored: {}", err)
+		end
+	end
+	Timer.stop()
+
+	local patchApplySuccess, unappliedPatch = pcall(self.__reconciler.applyPatch, self.__reconciler, patch)
+	if not patchApplySuccess then
+		if historyRecording then
+			ChangeHistoryService:FinishRecording(historyRecording, Enum.FinishRecordingOperation.Commit)
+		end
+		-- This might make a weird stack trace but the only way applyPatch can
+		-- fail is if a bug occurs so it's probably fine.
+		error(unappliedPatch)
+	end
+
+	if Settings:get("enableSyncFallback") and not PatchSet.isEmpty(unappliedPatch) then
+		-- Some changes did not apply, let's try replacing them instead
+		local addedIdList = PatchSet.addedIdList(unappliedPatch)
+		local updatedIdList = PatchSet.updatedIdList(unappliedPatch)
+
+		Log.debug("ServeSession:__replaceInstances(unappliedPatch.added)")
+		Timer.start("ServeSession:__replaceInstances(unappliedPatch.added)")
+		local addSuccess, unappliedAddedRefs = self:__replaceInstances(addedIdList)
+		Timer.stop()
+
+		Log.debug("ServeSession:__replaceInstances(unappliedPatch.updated)")
+		Timer.start("ServeSession:__replaceInstances(unappliedPatch.updated)")
+		local updateSuccess, unappliedUpdateRefs = self:__replaceInstances(updatedIdList)
+		Timer.stop()
+
+		-- Update the unapplied patch to reflect which Instances were replaced successfully
+		if addSuccess then
+			table.clear(unappliedPatch.added)
+			PatchSet.assign(unappliedPatch, unappliedAddedRefs)
+		end
+		if updateSuccess then
+			table.clear(unappliedPatch.updated)
+			PatchSet.assign(unappliedPatch, unappliedUpdateRefs)
+		end
+	end
+
+	if not PatchSet.isEmpty(unappliedPatch) then
+		Log.debug(
+			"Could not apply all changes requested by the Rojo server:\n{}",
+			PatchSet.humanSummary(self.__instanceMap, unappliedPatch)
+		)
+	end
+
+	Timer.start("postcommitCallbacks")
+	-- Postcommit callbacks can be called with spawn since regardless of firing order, they are
+	-- guaranteed to be called after the commit
+	for _, callback in self.__postcommitCallbacks do
+		task.spawn(function()
+			local success, err = pcall(callback, patch, self.__instanceMap, unappliedPatch)
+			if not success then
+				Log.warn("Postcommit hook errored: {}", err)
+			end
+		end)
+	end
+	Timer.stop()
+
+	if historyRecording then
+		ChangeHistoryService:FinishRecording(historyRecording, Enum.FinishRecordingOperation.Commit)
+	end
+end
+
 function ServeSession:__initialSync(serverInfo)
 	return self.__apiContext:read({ serverInfo.rootInstanceId }):andThen(function(readResponseBody)
 		-- Tell the API Context that we're up-to-date with the version of
@@ -216,11 +474,13 @@ function ServeSession:__initialSync(serverInfo)
 		-- For any instances that line up with the Rojo server's view, start
 		-- tracking them in the reconciler.
 		Log.trace("Matching existing Roblox instances to Rojo IDs")
+		self:setLoadingText("Hydrating instance map...")
 		self.__reconciler:hydrate(readResponseBody.instances, serverInfo.rootInstanceId, game)
 
 		-- Calculate the initial patch to apply to the DataModel to catch us
 		-- up to what Rojo thinks the place should look like.
 		Log.trace("Computing changes that plugin needs to make to catch up to server...")
+		self:setLoadingText("Finding differences between server and Studio...")
 		local success, catchUpPatch =
 			self.__reconciler:diff(readResponseBody.instances, serverInfo.rootInstanceId, game)
 
@@ -281,15 +541,7 @@ function ServeSession:__initialSync(serverInfo)
 
 			return self.__apiContext:write(inversePatch)
 		elseif userDecision == "Accept" then
-			local unappliedPatch = self.__reconciler:applyPatch(catchUpPatch)
+			self:__applyPatch(catchUpPatch)
-
-			if not PatchSet.isEmpty(unappliedPatch) then
-				Log.debug(
-					"Could not apply all changes requested by the Rojo server:\n{}",
-					PatchSet.humanSummary(self.__instanceMap, unappliedPatch)
-				)
-			end
-
 			return Promise.resolve()
 		else
 			return Promise.reject("Invalid user decision: " .. userDecision)
@@ -297,47 +549,6 @@ function ServeSession:__initialSync(serverInfo)
 	end)
 end
 
-function ServeSession:__mainSyncLoop()
-	return Promise.new(function(resolve, reject)
-		while self.__status == Status.Connected do
-			local success, result = self.__apiContext
-				:retrieveMessages()
-				:andThen(function(messages)
-					if self.__status == Status.Disconnected then
-						-- In the time it took to retrieve messages, we disconnected
-						-- so we just resolve immediately without patching anything
-						return
-					end
-
-					Log.trace("Serve session {} retrieved {} messages", tostring(self), #messages)
-
-					for _, message in messages do
-						local unappliedPatch = self.__reconciler:applyPatch(message)
-
-						if not PatchSet.isEmpty(unappliedPatch) then
-							Log.debug(
-								"Could not apply all changes requested by the Rojo server:\n{}",
-								PatchSet.humanSummary(self.__instanceMap, unappliedPatch)
-							)
-						end
-					end
-				end)
-				:await()
-
-			if self.__status == Status.Disconnected then
-				-- If we are no longer connected after applying, we stop silently
-				-- without checking for errors as they are no longer relevant
-				break
-			elseif success == false then
-				reject(result)
-			end
-		end
-
-		-- We are no longer connected, so we resolve the promise
-		resolve()
-	end)
-end
-
 function ServeSession:__stopInternal(err)
 	self:__setStatus(Status.Disconnected, err)
 	self.__apiContext:disconnect()

plugin/src/Settings.lua

@@ -12,12 +12,15 @@ local Roact = require(Packages.Roact)
 local defaultSettings = {
 	openScriptsExternally = false,
 	twoWaySync = false,
+	autoReconnect = false,
 	showNotifications = true,
-	syncReminder = true,
+	enableSyncFallback = true,
+	syncReminderMode = "Notify" :: "None" | "Notify" | "Fullscreen",
+	syncReminderPolling = true,
 	checkForUpdates = true,
 	checkForPrereleases = false,
 	autoConnectPlaytestServer = false,
-	confirmationBehavior = "Initial",
+	confirmationBehavior = "Initial" :: "Never" | "Initial" | "Large Changes" | "Unlisted PlaceId",
 	largeChangesConfirmationThreshold = 5,
 	playSounds = true,
 	typecheckingEnabled = false,
@@ -108,4 +111,14 @@ function Settings:getBinding(name)
 	return bind
 end
 
+function Settings:getBindings(...: string)
+	local bindings = {}
+	for i = 1, select("#", ...) do
+		local source = select(i, ...)
+		bindings[source] = self:getBinding(source)
+	end
+
+	return Roact.joinBindings(bindings)
+end
+
 return Settings

plugin/src/Types.lua

@@ -49,12 +49,31 @@ local ApiReadResponse = t.interface({
 	instances = t.map(RbxId, ApiInstance),
 })
 
-local ApiSubscribeResponse = t.interface({
+local SocketPacketType = t.union(t.literal("messages"))
-	sessionId = t.string,
+
+local MessagesPacket = t.interface({
 	messageCursor = t.number,
 	messages = t.array(ApiSubscribeMessage),
 })
 
+local SocketPacketBody = t.union(MessagesPacket)
+
+local ApiSocketPacket = t.interface({
+	sessionId = t.string,
+	packetType = SocketPacketType,
+	body = SocketPacketBody,
+})
+
+local ApiSerializeResponse = t.interface({
+	sessionId = t.string,
+	modelContents = t.buffer,
+})
+
+local ApiRefPatchResponse = t.interface({
+	sessionId = t.string,
+	patch = ApiSubscribeMessage,
+})
+
 local ApiError = t.interface({
 	kind = t.union(t.literal("NotFound"), t.literal("BadRequest"), t.literal("InternalError")),
 	details = t.string,
@@ -75,13 +94,15 @@ return strict("Types", {
 
 	ApiInfoResponse = ApiInfoResponse,
 	ApiReadResponse = ApiReadResponse,
-	ApiSubscribeResponse = ApiSubscribeResponse,
+	ApiSocketPacket = ApiSocketPacket,
 	ApiError = ApiError,
 
 	ApiInstance = ApiInstance,
 	ApiInstanceUpdate = ApiInstanceUpdate,
 	ApiInstanceMetadata = ApiInstanceMetadata,
 	ApiSubscribeMessage = ApiSubscribeMessage,
+	ApiSerializeResponse = ApiSerializeResponse,
+	ApiRefPatchResponse = ApiRefPatchResponse,
 	ApiValue = ApiValue,
 	RbxId = RbxId,
 

plugin/src/Version.lua

@@ -1,6 +1,20 @@
-local Packages = script.Parent.Parent.Packages
+local Rojo = script:FindFirstAncestor("Rojo")
+local Plugin = Rojo.Plugin
+local Packages = Rojo.Packages
+
 local Http = require(Packages.Http)
 local Promise = require(Packages.Promise)
+local Log = require(Packages.Log)
+
+local Config = require(Plugin.Config)
+local Settings = require(Plugin.Settings)
+local timeUtil = require(Plugin.timeUtil)
+
+type LatestReleaseInfo = {
+	version: { number },
+	prerelease: boolean,
+	publishedUnixTimestamp: number,
+}
 
 local function compare(a, b)
 	if a > b then
@@ -88,14 +102,26 @@ function Version.display(version)
 	return output
 end
 
+--[[
+	The GitHub API rate limit for unauthenticated requests is rather low,
+	and we don't release often enough to warrant checking it more than once a day.
+--]]
+Version._cachedLatestCompatible = nil :: {
+	value: LatestReleaseInfo?,
+	timestamp: number,
+}?
+
 function Version.retrieveLatestCompatible(options: {
 	version: { number },
 	includePrereleases: boolean?,
-}): {
+}): LatestReleaseInfo?
-	version: { number },
+	if Version._cachedLatestCompatible and os.clock() - Version._cachedLatestCompatible.timestamp < 60 * 60 * 24 then
-	prerelease: boolean,
+		Log.debug("Using cached latest compatible version")
-	publishedUnixTimestamp: number,
+		return Version._cachedLatestCompatible.value
-}?
+	end
+
+	Log.debug("Retrieving latest compatible version from GitHub")
+
 	local success, releases = Http.get("https://api.github.com/repos/rojo-rbx/rojo/releases?per_page=10")
 		:andThen(function(response)
 			if response.code >= 400 then
@@ -114,7 +140,7 @@ function Version.retrieveLatestCompatible(options: {
 	end
 
 	-- Iterate through releases, looking for the latest compatible version
-	local latestCompatible = nil
+	local latestCompatible: LatestReleaseInfo? = nil
 	for _, release in releases do
 		-- Skip prereleases if they are not requested
 		if (not options.includePrereleases) and release.prerelease then
@@ -142,10 +168,43 @@ function Version.retrieveLatestCompatible(options: {
 
 	-- Don't return anything if the latest found is not newer than the current version
 	if latestCompatible == nil or Version.compare(latestCompatible.version, options.version) <= 0 then
+		-- Cache as nil so we don't try again for a day
+		Version._cachedLatestCompatible = {
+			value = nil,
+			timestamp = os.clock(),
+		}
+
 		return nil
 	end
 
+	-- Cache the latest compatible version
+	Version._cachedLatestCompatible = {
+		value = latestCompatible,
+		timestamp = os.clock(),
+	}
+
 	return latestCompatible
 end
 
+function Version.getUpdateMessage(): string?
+	if not Settings:get("checkForUpdates") then
+		return
+	end
+
+	local isLocalInstall = string.find(debug.traceback(), "\n[^\n]-user_.-$") ~= nil
+	local latestCompatibleVersion = Version.retrieveLatestCompatible({
+		version = Config.version,
+		includePrereleases = isLocalInstall and Settings:get("checkForPrereleases"),
+	})
+	if not latestCompatibleVersion then
+		return
+	end
+
+	return string.format(
+		"A newer compatible version of Rojo, %s, was published %s! Go to the Rojo releases page to learn more.",
+		Version.display(latestCompatibleVersion.version),
+		timeUtil.elapsedToText(DateTime.now().UnixTimestamp - latestCompatibleVersion.publishedUnixTimestamp)
+	)
+end
+
 return Version

plugin/src/preloadAssets.lua

@@ -9,7 +9,7 @@ local gatherAssetUrlsRecursive
 function gatherAssetUrlsRecursive(currentTable, currentUrls)
 	currentUrls = currentUrls or {}
 
-	for _, value in pairs(currentTable) do
+	for _, value in currentTable do
 		if typeof(value) == "string" then
 			table.insert(currentUrls, value)
 		elseif typeof(value) == "table" then

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

@@ -1,16 +0,0 @@
----
-source: tests/tests/build.rs
-expression: contents
----
-<roblox version="4">
-  <Item class="Folder" referent="0">
-    <Properties>
-      <string name="Name">json_model_legacy_name</string>
-    </Properties>
-    <Item class="Folder" referent="1">
-      <Properties>
-        <string name="Name">Expected Name</string>
-      </Properties>
-    </Item>
-  </Item>
-</roblox>

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

@@ -0,0 +1,23 @@
+---
+source: tests/tests/build.rs
+assertion_line: 109
+expression: contents
+---
+<roblox version="4">
+  <Item class="DataModel" referent="0">
+    <Properties>
+      <string name="Name">model_json_name_input</string>
+    </Properties>
+    <Item class="Workspace" referent="1">
+      <Properties>
+        <string name="Name">Workspace</string>
+        <bool name="NeedsPivotMigration">false</bool>
+      </Properties>
+      <Item class="StringValue" referent="2">
+        <Properties>
+          <string name="Name">/Bar</string>
+        </Properties>
+      </Item>
+    </Item>
+  </Item>
+</roblox>

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

@@ -0,0 +1,20 @@
+---
+source: tests/tests/build.rs
+assertion_line: 108
+expression: contents
+---
+<roblox version="4">
+  <Item class="Folder" referent="0">
+    <Properties>
+      <string name="Name">slugified_name_roundtrip</string>
+    </Properties>
+    <Item class="Script" referent="1">
+      <Properties>
+        <string name="Name">/Script</string>
+        <token name="RunContext">0</token>
+        <string name="Source"><![CDATA[print("Hello world!")
+]]></string>
+      </Properties>
+    </Item>
+  </Item>
+</roblox>

rojo-test/build-tests/json_model_legacy_name/default.project.json

@@ -1,6 +0,0 @@
-{
-  "name": "json_model_legacy_name",
-  "tree": {
-    "$path": "folder"
-  }
-}

rojo-test/build-tests/json_model_legacy_name/folder/Expected Name.model.json

@@ -1,4 +0,0 @@
-{
-  "Name": "Overridden Name",
-  "ClassName": "Folder"
-}

rojo-test/build-tests/model_json_name_input/default.project.json

@@ -0,0 +1,11 @@
+{
+  "name": "model_json_name_input",
+  "tree": {
+    "$className": "DataModel",
+    "Workspace": {
+      "$className": "Workspace",
+      "$path": "src"
+    }
+  }
+}
+

rojo-test/build-tests/model_json_name_input/src/Bar.model.json

@@ -0,0 +1,5 @@
+{
+  "name": "/Bar",
+  "className": "StringValue"
+}
+

rojo-test/build-tests/slugified_name_roundtrip/_Script/init.meta.json

@@ -0,0 +1,4 @@
+{
+  "name": "/Script"
+}
+

rojo-test/build-tests/slugified_name_roundtrip/_Script/init.server.luau

@@ -0,0 +1,2 @@
+print("Hello world!")
+

rojo-test/build-tests/slugified_name_roundtrip/default.project.json

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

rojo-test/build-tests/slugified_name_roundtrip/src/_Script/init.meta.json

@@ -0,0 +1,3 @@
+{
+  "name": "/Script"
+}

rojo-test/build-tests/slugified_name_roundtrip/src/_Script/init.server.luau

@@ -0,0 +1 @@
+print("Hello world!")

rojo-test/serve-test-snapshots/end_to_end__tests__serve__add_folder_info.snap

@@ -6,7 +6,7 @@ expectedPlaceIds: ~
 gameId: ~
 placeId: ~
 projectName: add_folder
-protocolVersion: 4
+protocolVersion: 5
 rootInstanceId: id-2
 serverVersion: "[server-version]"
 sessionId: id-1

rojo-test/serve-test-snapshots/end_to_end__tests__serve__add_folder_subscribe.snap

@@ -1,19 +1,21 @@
 ---
 source: tests/tests/serve.rs
-expression: "subscribe_response.intern_and_redact(&mut redactions, ())"
+expression: "socket_packet.intern_and_redact(&mut redactions, ())"
 ---
-messageCursor: 1
+body:
-messages:
+  messageCursor: 1
-  - added:
+  messages:
-      id-3:
+    - added:
-        Children: []
+        id-3:
-        ClassName: Folder
+          Children: []
-        Id: id-3
+          ClassName: Folder
-        Metadata:
+          Id: id-3
-          ignoreUnknownInstances: false
+          Metadata:
-        Name: my-new-folder
+            ignoreUnknownInstances: false
-        Parent: id-2
+          Name: my-new-folder
-        Properties: {}
+          Parent: id-2
-    removed: []
+          Properties: {}
-    updated: []
+      removed: []
+      updated: []
+packetType: messages
 sessionId: id-1

rojo-test/serve-test-snapshots/end_to_end__tests__serve__add_optional_folder.snap

@@ -7,7 +7,7 @@ expectedPlaceIds: ~
 gameId: ~
 placeId: ~
 projectName: optional
-protocolVersion: 4
+protocolVersion: 5
 rootInstanceId: id-2
 serverVersion: "[server-version]"
 sessionId: id-1

rojo-test/serve-test-snapshots/end_to_end__tests__serve__edit_init_info.snap

@@ -6,7 +6,7 @@ expectedPlaceIds: ~
 gameId: ~
 placeId: ~
 projectName: edit_init
-protocolVersion: 4
+protocolVersion: 5
 rootInstanceId: id-2
 serverVersion: "[server-version]"
 sessionId: id-1