Prefer workspace for root_module path

Author: martingms

test/rust_analyzer/generated_srcs_test/rust_project_json_test.rs

@@ -48,7 +48,9 @@ mod tests {
             .find(|c| &c.display_name == "generated_srcs")
             .unwrap();
         assert!(gen.root_module.starts_with("/"));
-        assert!(gen.root_module.ends_with("/lib.rs"));
+        assert!(gen
+            .root_module
+            .ends_with("rules_rust_test_rust_analyzer/lib.rs"));
 
         let include_dirs = &gen.source.as_ref().unwrap().include_dirs;
         assert!(include_dirs.len() == 1);

tools/rust_analyzer/aquery.rs

@@ -208,6 +208,15 @@ fn consolidate_crate_specs(crate_specs: Vec<CrateSpec>) -> anyhow::Result<BTreeS
                     existing.proc_macro_dylib_path.replace(dylib_path.clone());
                 }
             }
+
+            // Prefer using workspace for root_module path if possible.
+            // A test crate might get an __EXEC_ROOT__-based root_module when depending
+            // on a library crate with mixed generated sources, for example.
+            if existing.root_module.starts_with("__EXEC_ROOT__")
+                && spec.root_module.starts_with("__WORKSPACE__")
+            {
+                existing.root_module = spec.root_module;
+            }
         } else {
             consolidated_specs.insert(spec.crate_id.clone(), spec);
         }