feat(sourcemap): Add support for sourcemap debug IDs (#6221)

The sourcemap [`debugId`
proposal](https://github.com/tc39/source-map/blob/main/proposals/debug-id.md)
adds globally unique build or debug IDs to source maps and generated
code, making build artifacts self-identifying.

Support for debug IDs was added to
[`rust-sourcemap`](getsentry/rust-sourcemap#66)
in 2023 and Sentry have made use of this to aid in matching up source
and sourcemap files without having to worry about path mismatches or
release versions.

I want to add debug ID support to Rolldown but it uses `oxc::sourcemap`
so it looks like I need to start here first!

Author: timfish

crates/oxc_sourcemap/src/decode.rs

@@ -23,6 +23,8 @@ pub struct JSONSourceMap {
     pub sources_content: Option<Vec<Option<String>>>,
     /// A list of symbol names used by the “mappings” entry.
     pub names: Vec<String>,
+    /// An optional field containing the debugId for this sourcemap.
+    pub debug_id: Option<String>,
 }
 
 pub fn decode(json: JSONSourceMap) -> Result<SourceMap> {
@@ -38,6 +40,7 @@ pub fn decode(json: JSONSourceMap) -> Result<SourceMap> {
         tokens,
         token_chunks: None,
         x_google_ignore_list: None,
+        debug_id: json.debug_id,
     })
 }
 

crates/oxc_sourcemap/src/encode.rs

@@ -21,6 +21,7 @@ pub fn encode(sourcemap: &SourceMap) -> JSONSourceMap {
             .as_ref()
             .map(|x| x.iter().map(ToString::to_string).map(Some).collect()),
         names: sourcemap.names.iter().map(ToString::to_string).collect(),
+        debug_id: sourcemap.get_debug_id().map(ToString::to_string),
     }
 }
 
@@ -76,6 +77,12 @@ pub fn encode_to_string(sourcemap: &SourceMap) -> String {
 
     contents.push("],\"mappings\":\"".into());
     contents.push(serialize_sourcemap_mappings(sourcemap).into());
+
+    if let Some(debug_id) = sourcemap.get_debug_id() {
+        contents.push("\",\"debugId\":\"".into());
+        contents.push(debug_id.into());
+    }
+
     contents.push("\"}".into());
 
     // Check we calculated number of segments required correctly
@@ -401,9 +408,10 @@ fn test_encode_escape_string() {
         None,
     );
     sm.set_x_google_ignore_list(vec![0]);
+    sm.set_debug_id("56431d54-c0a6-451d-8ea2-ba5de5d8ca2e");
     assert_eq!(
         sm.to_json_string(),
-        r#"{"version":3,"names":["name_length_greater_than_16_\u0000"],"sources":["\u0000"],"sourcesContent":["emoji-👀-\u0000"],"x_google_ignoreList":[0],"mappings":""}"#
+        r#"{"version":3,"names":["name_length_greater_than_16_\u0000"],"sources":["\u0000"],"sourcesContent":["emoji-👀-\u0000"],"x_google_ignoreList":[0],"mappings":"","debugId":"56431d54-c0a6-451d-8ea2-ba5de5d8ca2e"}"#
     );
 }
 

crates/oxc_sourcemap/src/sourcemap.rs

@@ -21,6 +21,7 @@ pub struct SourceMap {
     /// The `x_google_ignoreList` field refers to the `sources` array, and lists the indices of all the known third-party sources in that source map.
     /// When parsing the source map, developer tools can use this to determine sections of the code that the browser loads and runs that could be automatically ignore-listed.
     pub(crate) x_google_ignore_list: Option<Vec<u32>>,
+    pub(crate) debug_id: Option<String>,
 }
 
 #[allow(clippy::cast_possible_truncation)]
@@ -43,6 +44,7 @@ impl SourceMap {
             tokens,
             token_chunks,
             x_google_ignore_list: None,
+            debug_id: None,
         }
     }
 
@@ -95,6 +97,14 @@ impl SourceMap {
         self.x_google_ignore_list = Some(x_google_ignore_list);
     }
 
+    pub fn set_debug_id(&mut self, debug_id: &str) {
+        self.debug_id = Some(debug_id.into());
+    }
+
+    pub fn get_debug_id(&self) -> Option<&str> {
+        self.debug_id.as_deref()
+    }
+
     pub fn get_names(&self) -> impl Iterator<Item = &str> {
         self.names.iter().map(AsRef::as_ref)
     }