[WIP] rustdoc: Add tree-sitter syntax highlighting for non-Rust code blocks

Cargo.lock

@@ -170,6 +170,243 @@ dependencies = [
  "object 0.37.3",
 ]
 
+[[package]]
+name = "arborium"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f00a72aec131b90c1c6495c565c4e4842fdbaf137ea4cacec110d353937ab99d"
+dependencies = [
+ "arborium-bash",
+ "arborium-c",
+ "arborium-cpp",
+ "arborium-css",
+ "arborium-go",
+ "arborium-highlight",
+ "arborium-html",
+ "arborium-java",
+ "arborium-javascript",
+ "arborium-json",
+ "arborium-python",
+ "arborium-ruby",
+ "arborium-sql",
+ "arborium-theme",
+ "arborium-toml",
+ "arborium-tree-sitter",
+ "arborium-typescript",
+ "arborium-yaml",
+ "dlmalloc",
+]
+
+[[package]]
+name = "arborium-bash"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "34c6fd5230512b1191480100dd7876e972d1d6fd8e04fc62950a46b2a185405a"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-c"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6eb49d9d4d314d39e3ad41f891f3c46a417e21127c572621d3bb2b8acb0f67d2"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-cpp"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b3813b0fd9e61425fe387333eb77ff5a3ea890f66d89e1262a66372ecad1274f"
+dependencies = [
+ "arborium-c",
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-css"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5d95540ee6ea2c33f40b45d9c40283a5c396e0ceb8529c4f2151932e43858a3b"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-go"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d7f8df9adca3da8c9e36889e0f52ab359dd36d168bc677e65fce5f43ca66b0d"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-highlight"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2f2df668f0c80bfa2e437f74d45a4922a0e9256c2476560200774be4b60686f3"
+dependencies = [
+ "arborium-theme",
+ "arborium-tree-sitter",
+ "streaming-iterator",
+]
+
+[[package]]
+name = "arborium-html"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a8d898910e534cddb0dca62ff3789b94637979b16d5354f153235438f58d29d6"
+dependencies = [
+ "arborium-css",
+ "arborium-javascript",
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-java"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b91053783a4c3806cdcf92a7009bfe765ebcf0a13cd49ee361751a68f1f2c10f"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-javascript"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7220c71b1056508a028a4acfa4a10d8ca1713420ac3a36853dfd4a55bb335a4b"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-json"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "775321ffff8b71819c6dfead9e62bcd1efc1616306e59f2e1317ba7bef282e1f"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-python"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45c5db8f67870cc64b67933a644fb296b3c367e9bfd85aa222a1ff6d49883e25"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-ruby"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7391c3561e43b892241ef216aafa974e1c3a59cd4e29d9cb9a7febc41645c0a8"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-sql"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc2c5bd1ed383d8ed8f0269d0cfddb475af9c98580d43f76cc4bb85a6f052633"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-sysroot"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6d25c6fe8f35b7803048ca9f0846432011510d5196eb1089cf3a4bb37c35d094"
+dependencies = [
+ "cc",
+ "dlmalloc",
+]
+
+[[package]]
+name = "arborium-theme"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9da38b2109b8af45b7e0bce0c96f7db1c17831a62a23ae586c5705efac635758"
+
+[[package]]
+name = "arborium-toml"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b391b5bf276950b457d0b05efc0089c74b94e2f0939f8a63d98b4b84da5ebf12"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-tree-sitter"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "936e30ab0ba24131c37823d6d087b4ab6b7d59c6dd26fd1f1470e50582dc07ba"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "regex",
+ "regex-syntax",
+ "streaming-iterator",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-typescript"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9cd96fae6737d469b2042e2f7c37e37e6276465ba1c15162182e4106c189fc41"
+dependencies = [
+ "arborium-javascript",
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
+[[package]]
+name = "arborium-yaml"
+version = "2.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ef47437d2fe489ba8aa718dd1be3152b80b988b976183e84cfb1865a17cae1e8"
+dependencies = [
+ "arborium-sysroot",
+ "cc",
+ "tree-sitter-language",
+]
+
 [[package]]
 name = "arrayref"
 version = "0.3.9"
@@ -1265,6 +1502,17 @@ version = "1.0.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8975ffdaa0ef3661bfe02dbdcc06c9f829dfafe6a3c474de366a8d5e44276921"
 
+[[package]]
+name = "dlmalloc"
+version = "0.2.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6738d2e996274e499bc7b0d693c858b7720b9cd2543a0643a3087e6cb0a4fa16"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "windows-sys 0.61.2",
+]
+
 [[package]]
 name = "dyn-clone"
 version = "1.0.20"
@@ -4861,6 +5109,7 @@ dependencies = [
 name = "rustdoc"
 version = "0.0.0"
 dependencies = [
+ "arborium",
  "arrayvec",
  "askama",
  "base64",
@@ -5329,6 +5578,12 @@ version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
 
+[[package]]
+name = "streaming-iterator"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2b2231b7c3057d5e4ad0156fb3dc807d900806020c5ffa3ee6ff2c8c76fb8520"
+
 [[package]]
 name = "string_cache"
 version = "0.8.9"
@@ -5851,6 +6106,12 @@ dependencies = [
  "tracing-subscriber",
 ]
 
+[[package]]
+name = "tree-sitter-language"
+version = "0.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ae62f7eae5eb549c71b76658648b72cc6111f2d87d24a1e31fa907f4943e3ce"
+
 [[package]]
 name = "twox-hash"
 version = "1.6.3"

src/librustdoc/Cargo.toml

@@ -9,6 +9,23 @@ path = "lib.rs"
 
 [dependencies]
 # tidy-alphabetical-start
+arborium = { version = "2.0.0", default-features = false, features = [
+    "lang-bash",
+    "lang-c",
+    "lang-cpp",
+    "lang-css",
+    "lang-go",
+    "lang-html",
+    "lang-java",
+    "lang-javascript",
+    "lang-json",
+    "lang-python",
+    "lang-ruby",
+    "lang-sql",
+    "lang-toml",
+    "lang-typescript",
+    "lang-yaml",
+] }
 arrayvec = { version = "0.7", default-features = false }
 askama = { version = "0.14", default-features = false, features = ["alloc", "config", "derive"] }
 base64 = "0.21.7"

src/librustdoc/config.rs

@@ -312,6 +312,8 @@ pub(crate) struct RenderOptions {
     pub(crate) disable_minification: bool,
     /// If `true`, HTML source pages will generate the possibility to expand macros.
     pub(crate) generate_macro_expansion: bool,
+    /// If `true`, non-Rust code blocks will be syntax-highlighted using tree-sitter.
+    pub(crate) highlight_foreign_code: bool,
 }
 
 #[derive(Copy, Clone, Debug, PartialEq, Eq)]
@@ -805,6 +807,7 @@ impl Options {
         let no_capture = matches.opt_present("no-capture");
         let generate_link_to_definition = matches.opt_present("generate-link-to-definition");
         let generate_macro_expansion = matches.opt_present("generate-macro-expansion");
+        let highlight_foreign_code = matches.opt_present("highlight-foreign-code");
         let extern_html_root_takes_precedence =
             matches.opt_present("extern-html-root-takes-precedence");
         let html_no_source = matches.opt_present("html-no-source");
@@ -916,6 +919,7 @@ impl Options {
             include_parts_dir,
             parts_out_dir,
             disable_minification,
+            highlight_foreign_code,
         };
         Some((input, options, render_options, loaded_paths))
     }

src/librustdoc/externalfiles.rs

@@ -47,6 +47,7 @@ impl ExternalHtml {
                 edition,
                 playground,
                 heading_offset: HeadingOffset::H2,
+                highlight_foreign_code: false,
             }
             .write_into(&mut bc)
             .unwrap();
@@ -63,6 +64,7 @@ impl ExternalHtml {
                 edition,
                 playground,
                 heading_offset: HeadingOffset::H2,
+                highlight_foreign_code: false,
             }
             .write_into(&mut ac)
             .unwrap();

src/librustdoc/html/highlight.rs

@@ -1475,5 +1475,31 @@ fn string_without_closing_tag<T: Display>(
     }
 }
 
+/// Highlights non-Rust code using arborium (tree-sitter based).
+/// Returns `None` if the language is not supported, in which case
+/// the caller should fall back to plain escaped text.
+pub(crate) fn highlight_foreign_code(lang: &str, code: &str) -> Option<String> {
+    use std::cell::RefCell;
+
+    thread_local! {
+        static HIGHLIGHTER: RefCell<arborium::Highlighter> =
+            RefCell::new(arborium::Highlighter::new());
+    }
+
+    // Map common language aliases to arborium grammar names
+    let lang = match lang {
+        "js" => "javascript",
+        "ts" => "typescript",
+        "py" => "python",
+        "rb" => "ruby",
+        "sh" | "shell" | "zsh" => "bash",
+        "yml" => "yaml",
+        "c++" | "cxx" => "cpp",
+        other => other,
+    };
+
+    HIGHLIGHTER.with_borrow_mut(|h| h.highlight(lang, code).ok())
+}
+
 #[cfg(test)]
 mod tests;