Non-Typst highlighting in documentation

Cargo.lock

@@ -2495,6 +2495,7 @@ dependencies = [
  "pulldown-cmark",
  "serde",
  "serde_yaml",
+ "syntect",
  "typed-arena",
  "typst",
  "typst-library",

docs/Cargo.toml

@@ -20,6 +20,7 @@ once_cell = "1"
 pulldown-cmark = "0.9"
 serde = { version = "1", features = ["derive"] }
 serde_yaml = "0.8"
+syntect = { version = "5", default-features = false, features = ["parsing", "html", "regex-fancy"] }
 typed-arena = "2"
 unicode_names2 = "0.6.0"
 unscanny = "0.1"

docs/src/html.rs

@@ -1,7 +1,6 @@
 use std::ops::Range;
 
 use comemo::Prehashed;
-use md::escape::escape_html;
 use pulldown_cmark as md;
 use typed_arena::Arena;
 use typst::diag::FileResult;
@@ -402,11 +401,22 @@ fn code_block(resolver: &dyn Resolver, lang: &str, text: &str) -> Html {
         }
     }
 
-    if !matches!(lang, "example" | "typ") {
+    if lang.is_empty() {
         let mut buf = String::from("<pre>");
-        escape_html(&mut buf, &display).unwrap();
+        md::escape::escape_html(&mut buf, &display).unwrap();
         buf.push_str("</pre>");
         return Html::new(buf);
+    } else if !matches!(lang, "example" | "typ") {
+        let set = &*typst_library::text::SYNTAXES;
+        let buf = syntect::html::highlighted_html_for_string(
+            &display,
+            set,
+            set.find_syntax_by_token(lang)
+                .unwrap_or_else(|| panic!("unsupported highlighting language: {lang}")),
+            &typst_library::text::THEME,
+        )
+        .expect("failed to highlight code");
+        return Html::new(buf);
     }
 
     let root = typst::syntax::parse(&display);

library/src/text/raw.rs

@@ -343,7 +343,7 @@ fn to_syn(RgbaColor { r, g, b, a }: RgbaColor) -> synt::Color {
 /// syntaxes/02_Extra/VimHelp.sublime-syntax
 /// syntaxes/02_Extra/cmd-help/syntaxes/cmd-help.sublime-syntax
 /// ```
-static SYNTAXES: Lazy<syntect::parsing::SyntaxSet> =
+pub static SYNTAXES: Lazy<syntect::parsing::SyntaxSet> =
     Lazy::new(|| syntect::dumps::from_binary(include_bytes!("../../assets/syntect.bin")));
 
 /// The default theme used for syntax highlighting.