Fix Cider and informative data from the cache.

This should fix the navigation issue that was introduced after
switching to a more compact form of storing element models.

Change-Id: I1010be3595830713aab2ae5f35b5ce7bc8691734
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/201121
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

pkg/analyzer/lib/src/dart/micro/library_graph.dart

@@ -91,8 +91,13 @@ class FileState {
   Uint8List? informativeBytes;
   LibraryCycle? _libraryCycle;
 
-  /// id of the cache entry.
-  late int id;
+  /// id of the cache entry with unlinked data.
+  late int unlinkedId;
+
+  /// id of the cache entry with informative data.
+  /// We use a separate entry because there is no good way to efficiently
+  /// store a raw byte array.
+  late int informativeId;
 
   FileState._(
     this._fsState,
@@ -225,16 +230,23 @@ class FileState {
       _exists = _digest.isNotEmpty;
     });
 
-    String unlinkedKey = path;
+    String unlinkedKey = '$path.unlinked';
+    String informativeKey = '$path.informative';
 
     // Prepare bytes of the unlinked bundle - existing or new.
     // TODO(migration): should not be nullable
-    List<int>? bytes;
+    List<int>? unlinkedBytes;
+    List<int>? informativeBytes;
     {
-      var cacheData = _fsState._byteStore.get(unlinkedKey, _digest);
-      bytes = cacheData?.bytes;
+      var unlinkedData = _fsState._byteStore.get(unlinkedKey, _digest);
+      var informativeData = _fsState._byteStore.get(informativeKey, _digest);
+      unlinkedBytes = unlinkedData?.bytes;
+      informativeBytes = informativeData?.bytes;
 
-      if (bytes == null || bytes.isEmpty) {
+      if (unlinkedBytes == null ||
+          unlinkedBytes.isEmpty ||
+          informativeBytes == null ||
+          informativeBytes.isEmpty) {
         var content = performance.run('content', (_) {
           return getContent();
         });
@@ -245,26 +257,36 @@ class FileState {
           return parse(AnalysisErrorListener.NULL_LISTENER, content);
         });
 
-        informativeBytes = writeUnitInformative(unit);
-
         performance.run('unlinked', (performance) {
           var unlinkedBuilder = serializeAstCiderUnlinked(_digest, unit);
-          bytes = unlinkedBuilder.toBuffer();
-          performance.getDataInt('length').add(bytes!.length);
-          cacheData = _fsState._byteStore.putGet(unlinkedKey, _digest, bytes!);
-          bytes = cacheData!.bytes;
+          unlinkedBytes = unlinkedBuilder.toBuffer();
+          performance.getDataInt('length').add(unlinkedBytes!.length);
+          unlinkedData =
+              _fsState._byteStore.putGet(unlinkedKey, _digest, unlinkedBytes!);
+          unlinkedBytes = unlinkedData!.bytes;
+        });
+
+        performance.run('informative', (performance) {
+          informativeBytes = writeUnitInformative(unit);
+          performance.getDataInt('length').add(informativeBytes!.length);
+          informativeData = _fsState._byteStore
+              .putGet(informativeKey, _digest, informativeBytes!);
+          informativeBytes = informativeData!.bytes;
         });
 
         performance.run('prefetch', (_) {
-          unlinked2 = CiderUnlinkedUnit.fromBuffer(bytes!).unlinkedUnit!;
+          var decoded = CiderUnlinkedUnit.fromBuffer(unlinkedBytes!);
+          unlinked2 = decoded.unlinkedUnit!;
           _prefetchDirectReferences(unlinked2);
         });
       }
-      id = cacheData!.id;
+      unlinkedId = unlinkedData!.id;
+      informativeId = informativeData!.id;
+      this.informativeBytes = Uint8List.fromList(informativeBytes!);
     }
 
     // Read the unlinked bundle.
-    unlinked2 = CiderUnlinkedUnit.fromBuffer(bytes!).unlinkedUnit!;
+    unlinked2 = CiderUnlinkedUnit.fromBuffer(unlinkedBytes!).unlinkedUnit!;
     _apiSignature = Uint8List.fromList(unlinked2.apiSignature);
 
     // Build the graph.
@@ -570,8 +592,12 @@ class FileSystemState {
   /// Clears all the cached files. Returns the list of ids of all the removed
   /// files.
   Set<int> collectSharedDataIdentifiers() {
-    var files = _pathToFile.values.map((file) => file.id).toSet();
-    return files;
+    var result = <int>{};
+    for (var file in _pathToFile.values) {
+      result.add(file.unlinkedId);
+      result.add(file.informativeId);
+    }
+    return result;
   }
 
   FeatureSet contextFeatureSet(

pkg/analyzer/lib/src/dart/micro/resolve_file.dart

@@ -167,7 +167,8 @@ class FileResolver {
 
     // Schedule disposing references to cached unlinked data.
     for (var removedFile in removedFiles) {
-      removedCacheIds.add(removedFile.id);
+      removedCacheIds.add(removedFile.unlinkedId);
+      removedCacheIds.add(removedFile.informativeId);
     }
 
     // Remove libraries represented by removed files.
@@ -406,7 +407,8 @@ class FileResolver {
   void removeFilesNotNecessaryForAnalysisOf(List<String> files) {
     var removedFiles = fsState!.removeUnusedFiles(files);
     for (var removedFile in removedFiles) {
-      removedCacheIds.add(removedFile.id);
+      removedCacheIds.add(removedFile.unlinkedId);
+      removedCacheIds.add(removedFile.informativeId);
     }
   }
 

pkg/analyzer/test/src/dart/micro/simple_file_resolver_test.dart

@@ -792,6 +792,63 @@ var foo = 0;
     expect(result.lineInfo.lineStarts, [0, 11, 24]);
   }
 
+  test_nameOffset_class_method_fromBytes() async {
+    newFile('/workspace/dart/test/lib/a.dart', content: r'''
+class A {
+  void foo() {}
+}
+''');
+
+    addTestFile(r'''
+import 'a.dart';
+
+void f(A a) {
+  a.foo();
+}
+''');
+
+    await resolveTestFile();
+    {
+      var element = findNode.simple('foo();').staticElement!;
+      expect(element.nameOffset, 17);
+    }
+
+    // New resolver.
+    // Element models will be loaded from the cache.
+    createFileResolver();
+    await resolveTestFile();
+    {
+      var element = findNode.simple('foo();').staticElement!;
+      expect(element.nameOffset, 17);
+    }
+  }
+
+  test_nameOffset_unit_variable_fromBytes() async {
+    newFile('/workspace/dart/test/lib/a.dart', content: r'''
+var a = 0;
+''');
+
+    addTestFile(r'''
+import 'a.dart';
+var b = a;
+''');
+
+    await resolveTestFile();
+    {
+      var element = findNode.simple('a;').staticElement!;
+      expect(element.nameOffset, 4);
+    }
+
+    // New resolver.
+    // Element models will be loaded from the cache.
+    createFileResolver();
+    await resolveTestFile();
+    {
+      var element = findNode.simple('a;').staticElement!;
+      expect(element.nameOffset, 4);
+    }
+  }
+
   test_nullSafety_enabled() async {
     typeToStringWithNullability = true;