mirrors/bun.sh
1
0
Fork 0
mirror of https://github.com/oven-sh/bun synced 2026-02-14 12:51:54 +00:00
Code Issues Packages Projects Releases Wiki Activity

CRITICAL FIX: Register user-provided source maps in module loader

Browse Source 
The root cause was that when Bun transpiles files, it registers the source
maps in vm.source_mappings via putMappings(). However, when a file is plain
JavaScript with a user-provided sourcemap, Bun doesn't transpile it, so
there's no cache entry, and putMappings() was never called.

Solution: Added else-if blocks in ModuleLoader.zig after both putMappings()
calls to check if --enable-source-maps is enabled. If it is and there's no
cache entry, we now:
1. Check for sourceMappingURL comment in the source
2. Parse the source map (inline or external)
3. Register it in vm.source_mappings via putValue()

This ensures that user-provided source maps are available when stack traces
are formatted, allowing resolveSourceMapping() to find them.

Locations modified:
- ModuleLoader.zig:1192 - After first putMappings call
- ModuleLoader.zig:2546 - After second putMappings call
This commit is contained in:
Claude Bot
2025-10-09 15:59:41 +00:00
parent 52c41ed931
commit ef8148f7f2
1 changed files with 63 additions and 0 deletions
Download Patch File Download Diff File Expand all files Collapse all files

63
src/bun.js/ModuleLoader.zig
View File

@@ -1189,6 +1189,39 @@ pub fn transpileSourceCode(
break :brk ResolvedSource.Tag.javascript;
},
};
} else if (bun.sourcemap.JSSourceMap.@"--enable-source-maps") {
// When --enable-source-maps is enabled and there's no cache entry (i.e., file wasn't transpiled),
// check if the source has a user-provided sourceMappingURL and register it
const source_contents = source.contents;
if (bun.strings.lastIndexOfChar(source_contents, '\n')) |last_newline| {
const last_lines = source_contents[last_newline..];
if (bun.strings.indexOf(last_lines, "//# sourceMappingURL=")) |url_idx| {
const url_start = last_newline + url_idx + "//# sourceMappingURL=".len;
const url_end = bun.strings.indexOfChar(source_contents[url_start..], '\n') orelse
(source_contents.len - url_start);
const source_map_url = bun.strings.trim(source_contents[url_start..][0..url_end], " \r\t");
// Use a stack fallback allocator for temporary parsing
var sfb = std.heap.stackFallback(8192, bun.default_allocator);
const temp_alloc = sfb.get();
// Try to parse the sourcemap URL (handles both inline and external)
const parse = SourceMap.parseUrl(
bun.default_allocator,
temp_alloc,
source_map_url,
.mappings_only,
) catch null;
if (parse) |p| {
if (p.map) |map| {
// Register the parsed source map
map.ref();
jsc_vm.source_mappings.putValue(source.path.text, SavedSourceMap.Value.init(map)) catch {};
}
}
}
}
}
const start_count = jsc_vm.transpiler.linker.import_counter;
@@ -2510,6 +2543,36 @@ pub const RuntimeTranspilerStore = struct {
};
return;
} else if (bun.sourcemap.JSSourceMap.@"--enable-source-maps") {
// When --enable-source-maps is enabled and there's no cache entry,
// check if the source has a user-provided sourceMappingURL and register it
const source_contents = parse_result.source.contents;
if (bun.strings.lastIndexOfChar(source_contents, '\n')) |last_newline| {
const last_lines = source_contents[last_newline..];
if (bun.strings.indexOf(last_lines, "//# sourceMappingURL=")) |url_idx| {
const url_start = last_newline + url_idx + "//# sourceMappingURL=".len;
const url_end = bun.strings.indexOfChar(source_contents[url_start..], '\n') orelse
(source_contents.len - url_start);
const source_map_url = bun.strings.trim(source_contents[url_start..][0..url_end], " \r\t");
var sfb = std.heap.stackFallback(8192, bun.default_allocator);
const temp_alloc = sfb.get();
const parse = SourceMap.parseUrl(
bun.default_allocator,
temp_alloc,
source_map_url,
.mappings_only,
) catch null;
if (parse) |p| {
if (p.map) |map| {
map.ref();
vm.source_mappings.putValue(parse_result.source.path.text, SavedSourceMap.Value.init(map)) catch {};
}
}
}
}
}
if (parse_result.already_bundled != .none) {