Merge #8624

8624: Automatically detect rust library source file map  r=vsrs a=vsrs

This PR adds a new possible `rust-analyzer.debug.sourceFileMap` value:
```json
{
    "rust-analyzer.debug.sourceFileMap": "auto"
}
```

I did not make it the default because it uses two shell calls (`rustc --print sysroot` and `rustc -V -v`). First one can be slow (https://github.com/rust-lang/rustup/issues/783)

Fixes #8619

Co-authored-by: vsrs <[email protected]>

1 files changed, 6 insertions, 2 deletions

diff --git a/editors/code/src/config.ts b/editors/code/src/config.ts
index 03f7d7cc3..e858f80bc 100644
--- a/editors/code/src/config.ts
+++ b/editors/code/src/config.ts
@@ -135,8 +135,12 @@ export class Config {
     }
 
     get debug() {
-        // "/rustc/<id>" used by suggestions only.
-        const { ["/rustc/<id>"]: _, ...sourceFileMap } = this.get<Record<string, string>>("debug.sourceFileMap");
+        let sourceFileMap = this.get<Record<string, string> | "auto">("debug.sourceFileMap");
+        if (sourceFileMap !== "auto") {
+            // "/rustc/<id>" used by suggestions only.
+            const { ["/rustc/<id>"]: _, ...trimmed } = this.get<Record<string, string>>("debug.sourceFileMap");
+            sourceFileMap = trimmed;
+        }
 
         return {
             engine: this.get<string>("debug.engine"),