Merge pull request #42 from alexggh/fix/vscode_indexing

Speedup indexing with vscode + rustanalyzer

src/lib.rs

@@ -162,6 +162,7 @@ type Cache = BTreeMap<String, CacheEntry>;
 struct CacheEntry {
     manifest_ts: SystemTime,
     workspace_manifest_ts: SystemTime,
+    workspace_manifest_path: PathBuf,
     crate_names: CrateNames,
 }
 
@@ -186,17 +187,16 @@ pub fn crate_name(orig_name: &str) -> Result<FoundCrate, Error> {
     let manifest_dir = env::var("CARGO_MANIFEST_DIR").map_err(|_| Error::CargoManifestDirNotSet)?;
     let manifest_path = Path::new(&manifest_dir).join("Cargo.toml");
 
-    let workspace_manifest_path = workspace_manifest_path(&manifest_path)?;
-
     let manifest_ts = cargo_toml_timestamp(&manifest_path)?;
-    let workspace_manifest_ts = cargo_toml_timestamp(&workspace_manifest_path)?;
 
     static CACHE: Mutex<Cache> = Mutex::new(BTreeMap::new());
     let mut cache = CACHE.lock().unwrap();
 
     let crate_names = match cache.entry(manifest_dir) {
         btree_map::Entry::Occupied(entry) => {
             let cache_entry = entry.into_mut();
+            let workspace_manifest_path = cache_entry.workspace_manifest_path.as_path();
+            let workspace_manifest_ts = cargo_toml_timestamp(&workspace_manifest_path)?;
 
             // Timestamp changed, rebuild this cache entry.
             if manifest_ts != cache_entry.manifest_ts ||
@@ -213,6 +213,9 @@ pub fn crate_name(orig_name: &str) -> Result<FoundCrate, Error> {
             &cache_entry.crate_names
         },
         btree_map::Entry::Vacant(entry) => {
+            let workspace_manifest_path = workspace_manifest_path(&manifest_path)?;
+            let workspace_manifest_ts = cargo_toml_timestamp(&workspace_manifest_path)?;
+
             let cache_entry = entry.insert(read_cargo_toml(
                 &manifest_path,
                 &workspace_manifest_path,
@@ -273,7 +276,12 @@ fn read_cargo_toml(
 
     let crate_names = extract_crate_names(&manifest, workspace_dependencies)?;
 
-    Ok(CacheEntry { manifest_ts, workspace_manifest_ts, crate_names })
+    Ok(CacheEntry {
+        manifest_ts,
+        workspace_manifest_ts,
+        crate_names,
+        workspace_manifest_path: workspace_manifest_path.to_path_buf(),
+    })
 }
 
 /// Extract all `[workspace.dependencies]`.