Merge pull request #24206 from Microsoft/documentRegistery

Cache the latest source file from document registery in script info so that we do not have to reparse orphan script info

src/services/documentRegistry.ts

@@ -87,9 +87,18 @@ namespace ts {
 
         releaseDocumentWithKey(path: Path, key: DocumentRegistryBucketKey): void;
 
+        /*@internal*/
+        getLanguageServiceRefCounts(path: Path): [string, number | undefined][];
+
         reportStats(): string;
     }
 
+    /*@internal*/
+    export interface ExternalDocumentCache {
+        setDocument(key: DocumentRegistryBucketKey, path: Path, sourceFile: SourceFile): void;
+        getDocument(key: DocumentRegistryBucketKey, path: Path): SourceFile | undefined;
+    }
+
     export type DocumentRegistryBucketKey = string & { __bucketKey: any };
 
     interface DocumentRegistryEntry {
@@ -99,10 +108,14 @@ namespace ts {
         // language services are referencing the file, then the file can be removed from the
         // registry.
         languageServiceRefCount: number;
-        owners: string[];
     }
 
-    export function createDocumentRegistry(useCaseSensitiveFileNames?: boolean, currentDirectory = ""): DocumentRegistry {
+    export function createDocumentRegistry(useCaseSensitiveFileNames?: boolean, currentDirectory?: string): DocumentRegistry {
+        return createDocumentRegistryInternal(useCaseSensitiveFileNames, currentDirectory);
+    }
+
+    /*@internal*/
+    export function createDocumentRegistryInternal(useCaseSensitiveFileNames?: boolean, currentDirectory = "", externalCache?: ExternalDocumentCache): DocumentRegistry {
         // Maps from compiler setting target (ES3, ES5, etc.) to all the cached documents we have
         // for those settings.
         const buckets = createMap<Map<DocumentRegistryEntry>>();
@@ -123,12 +136,11 @@ namespace ts {
         function reportStats() {
             const bucketInfoArray = arrayFrom(buckets.keys()).filter(name => name && name.charAt(0) === "_").map(name => {
                 const entries = buckets.get(name);
-                const sourceFiles: { name: string; refCount: number; references: string[]; }[] = [];
+                const sourceFiles: { name: string; refCount: number; }[] = [];
                 entries.forEach((entry, name) => {
                     sourceFiles.push({
                         name,
-                        refCount: entry.languageServiceRefCount,
-                        references: entry.owners.slice(0)
+                        refCount: entry.languageServiceRefCount
                     });
                 });
                 sourceFiles.sort((x, y) => y.refCount - x.refCount);
@@ -173,14 +185,27 @@ namespace ts {
             const bucket = getBucketForCompilationSettings(key, /*createIfMissing*/ true);
             let entry = bucket.get(path);
             const scriptTarget = scriptKind === ScriptKind.JSON ? ScriptTarget.JSON : compilationSettings.target;
+            if (!entry && externalCache) {
+                const sourceFile = externalCache.getDocument(key, path);
+                if (sourceFile) {
+                    Debug.assert(acquiring);
+                    entry = {
+                        sourceFile,
+                        languageServiceRefCount: 0
+                    };
+                    bucket.set(path, entry);
+                }
+            }
+
             if (!entry) {
                 // Have never seen this file with these settings.  Create a new source file for it.
                 const sourceFile = createLanguageServiceSourceFile(fileName, scriptSnapshot, scriptTarget, version, /*setNodeParents*/ false, scriptKind);
-
+                if (externalCache) {
+                    externalCache.setDocument(key, path, sourceFile);
+                }
                 entry = {
                     sourceFile,
                     languageServiceRefCount: 1,
-                    owners: []
                 };
                 bucket.set(path, entry);
             }
@@ -191,6 +216,9 @@ namespace ts {
                 if (entry.sourceFile.version !== version) {
                     entry.sourceFile = updateLanguageServiceSourceFile(entry.sourceFile, scriptSnapshot, version,
                         scriptSnapshot.getChangeRange(entry.sourceFile.scriptSnapshot));
+                    if (externalCache) {
+                        externalCache.setDocument(key, path, entry.sourceFile);
+                    }
                 }
 
                 // If we're acquiring, then this is the first time this LS is asking for this document.
@@ -202,6 +230,7 @@ namespace ts {
                     entry.languageServiceRefCount++;
                 }
             }
+            Debug.assert(entry.languageServiceRefCount !== 0);
 
             return entry.sourceFile;
         }
@@ -225,6 +254,13 @@ namespace ts {
             }
         }
 
+        function getLanguageServiceRefCounts(path: Path) {
+            return arrayFrom(buckets.entries(), ([key, bucket]): [string, number | undefined] => {
+                const entry = bucket.get(path);
+                return [key, entry && entry.languageServiceRefCount];
+            });
+        }
+
         return {
             acquireDocument,
             acquireDocumentWithKey,
@@ -232,6 +268,7 @@ namespace ts {
             updateDocumentWithKey,
             releaseDocument,
             releaseDocumentWithKey,
+            getLanguageServiceRefCounts,
             reportStats,
             getKeyForCompilationSettings
         };