Fine. Fix for matching AST when add/remove tokens at the end.

Change-Id: I3ef648383f183cdfe9f7698218a2188ae050d02c
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/444540
Commit-Queue: Konstantin Shcheglov <[email protected]>
Reviewed-by: Johnni Winther <[email protected]>

Author: scheglov

pkg/analyzer/lib/src/fine/manifest_ast.dart

@@ -142,6 +142,10 @@ class ManifestNode {
     var tokenOffset = 0;
     var token = node.beginToken;
     while (true) {
+      if (tokenIndex >= tokenLengthList.length) {
+        return false;
+      }
+
       var tokenLength = token.lexeme.length;
       if (tokenLengthList[tokenIndex++] != tokenLength) {
         return false;
@@ -158,6 +162,10 @@ class ManifestNode {
       token = token.next ?? (throw StateError('endToken not found'));
     }
 
+    if (tokenIndex != tokenLengthList.length) {
+      return false;
+    }
+
     var collector = _ElementCollector(
       indexOfTypeParameter: context.indexOfTypeParameter,
       indexOfFormalParameter: context.indexOfFormalParameter,

pkg/analyzer/test/src/dart/analysis/driver_test.dart

@@ -43997,6 +43997,98 @@ const b = 0 as int;
     );
   }
 
+  test_manifest_constInitializer_identifier_addIdentifier() async {
+    configuration.withElementManifests = true;
+    await _runLibraryManifestScenario(
+      initialCode: r'''
+@foo
+class A {}
+''',
+      expectedInitialEvents: r'''
+[operation] linkLibraryCycle SDK
+[operation] linkLibraryCycle
+  package:test/test.dart
+    declaredClasses
+      A: #M0
+        metadata
+          [0]
+            tokenBuffer: @foo
+            tokenLengthList: [1, 3]
+            elementIndexList
+              0 = null
+              0 = null
+        supertype: Object @ dart:core
+        interface: #M1
+''',
+      updatedCode: r'''
+@foo.bar
+class A {}
+''',
+      expectedUpdatedEvents: r'''
+[operation] linkLibraryCycle
+  package:test/test.dart
+    declaredClasses
+      A: #M2
+        metadata
+          [0]
+            tokenBuffer: @foo.bar
+            tokenLengthList: [1, 3, 1, 3]
+            elementIndexList
+              0 = null
+              0 = null
+              0 = null
+        supertype: Object @ dart:core
+        interface: #M3
+''',
+    );
+  }
+
+  test_manifest_constInitializer_identifierIdentifier_removeIdentifier() async {
+    configuration.withElementManifests = true;
+    await _runLibraryManifestScenario(
+      initialCode: r'''
+@foo.bar
+class A {}
+''',
+      expectedInitialEvents: r'''
+[operation] linkLibraryCycle SDK
+[operation] linkLibraryCycle
+  package:test/test.dart
+    declaredClasses
+      A: #M0
+        metadata
+          [0]
+            tokenBuffer: @foo.bar
+            tokenLengthList: [1, 3, 1, 3]
+            elementIndexList
+              0 = null
+              0 = null
+              0 = null
+        supertype: Object @ dart:core
+        interface: #M1
+''',
+      updatedCode: r'''
+@foo
+class A {}
+''',
+      expectedUpdatedEvents: r'''
+[operation] linkLibraryCycle
+  package:test/test.dart
+    declaredClasses
+      A: #M2
+        metadata
+          [0]
+            tokenBuffer: @foo
+            tokenLengthList: [1, 3]
+            elementIndexList
+              0 = null
+              0 = null
+        supertype: Object @ dart:core
+        interface: #M3
+''',
+    );
+  }
+
   test_manifest_constInitializer_importPrefixReference() async {
     configuration.withElementManifests = true;
     await _runLibraryManifestScenario(