From d2e5d475bc1e176091b8ed240d6e1a2dea17c721 Mon Sep 17 00:00:00 2001
From: Konstantin Shcheglov <scheglov@google.com>
Date: Mon, 14 Dec 2020 05:37:37 +0000
Subject: [PATCH] Fix for crash when annotation references synthtic constructor
 of a generic class alias.

FAILURE: mixi@:class<s=a(=m
[NoSuchMethodError: The getter 'enclosingElement' was called on null.
Receiver: null
Tried calling: enclosingElement, #0      Object.noSuchMethod (dart:core-patch/object_patch.dart:54:5)
#1      LinkedResolutionReader.nextElement (package:analyzer/src/summary2/bundle_reader.dart:602:22)
#2      ApplyResolutionVisitor._nextElement (package:analyzer/src/summary2/apply_resolution.dart:1106:24)
#3      ApplyResolutionVisitor.visitAnnotation (package:analyzer/src/summary2/apply_resolution.dart:83:20)
#4      AnnotationImpl.accept (package:analyzer/src/dart/ast/ast.dart:280:49)
#5      NodeListImpl.accept (package:analyzer/src/dart/ast/ast.dart:7611:20)
#6      ApplyResolutionVisitor.visitClassTypeAlias (package:analyzer/src/summary2/apply_resolution.dart:167:20)
#7      ClassTypeAliasImpl.accept (package:analyzer/src/dart/ast/ast.dart:1794:49)
#8      LinkedContext.applyResolution (package:analyzer/src/summary2/bundle_reader.dart:512:11)
#9      LinkedUnitContext.applyResolution (package:analyzer/src/summary2/linked_unit_context.dart:93:25)
#10     ElementImpl.metadata (package:analyzer/src/dart/element/element.dart:2893:21)
#11     ResolutionVisitor.visitClassTypeAlias (package:analyzer/src/dart/resolver/resolution_visitor.dart:256:51)
#12     ClassTypeAliasImpl.accept (package:analyzer/src/dart/ast/ast.dart:1794:49)
#13     NodeListImpl.accept (package:analyzer/src/dart/ast/ast.dart:7611:20)
#14     CompilationUnitImpl.visitChildren (package:analyzer/src/dart/ast/ast.dart:2141:21)
#15     RecursiveAstVisitor.visitCompilationUnit (package:analyzer/dart/ast/visitor.dart:731:10)
#16     CompilationUnitImpl.accept (package:analyzer/src/dart/ast/ast.dart:2134:49)
#17     LibraryAnalyzer._resolveFile (package:analyzer/src/dart/analysis/library_analyzer.dart:680:10)
#18     LibraryAnalyzer.analyzeSync.<anonymous closure> (package:analyzer/src/dart/analysis/library_analyzer.dart:139:7)
#19     _LinkedHashMapMixin.forEach (dart:collection-patch/compact_hash.dart:387:8)
#20     LibraryAnalyzer.analyzeSync (package:analyzer/src/dart/analysis/library_analyzer.dart:138:11)
#21     LibraryAnalyzer.analyze (package:analyzer/src/dart/analysis/library_analyzer.dart:107:12)
#22     AnalysisDriver._computeResolvedLibrary2.<anonymous closure> (package:analyzer/src/dart/analysis/driver.dart:1414:65)
#23     PerformanceLog.run (package:analyzer/src/dart/analysis/performance_logger.dart:32:15)
#24     AnalysisDriver._computeResolvedLibrary2 (package:analyzer/src/dart/analysis/driver.dart:1400:20)
#25     AnalysisDriver._computeResolvedLibrary.<anonymous closure> (package:analyzer/src/dart/analysis/driver.dart:1393:15)


Change-Id: I6f04a325b30d9dc61e7eb1a4bba91ed8b9bcd1d3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/176060
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
---
 .../lib/src/dart/element/element.dart         |   8 +-
 .../test/src/summary/resynthesize_common.dart | 100 ++++++++++++++++++
 2 files changed, 106 insertions(+), 2 deletions(-)

diff --git a/pkg/analyzer/lib/src/dart/element/element.dart b/pkg/analyzer/lib/src/dart/element/element.dart
index 5c726991df94f..d23a5ab40b253 100644
--- a/pkg/analyzer/lib/src/dart/element/element.dart
+++ b/pkg/analyzer/lib/src/dart/element/element.dart
@@ -956,9 +956,13 @@ class ClassElementImpl extends AbstractClassElementImpl
     // substituting type parameters as appropriate.
     return constructorsToForward
         .map((ConstructorElement superclassConstructor) {
-      ConstructorElementImpl implicitConstructor =
-          ConstructorElementImpl(superclassConstructor.name, -1);
+      var containerRef = reference.getChild('@constructor');
+      var name = superclassConstructor.name;
+      var implicitConstructor = ConstructorElementImpl.forLinkedNode(
+          this, containerRef.getChild(name), null);
       implicitConstructor.isSynthetic = true;
+      implicitConstructor.name = name;
+      implicitConstructor.nameOffset = -1;
       implicitConstructor.redirectedConstructor = superclassConstructor;
       var hasMixinWithInstanceVariables = mixins.any(typeHasInstanceVariables);
       implicitConstructor.isConst =
diff --git a/pkg/analyzer/test/src/summary/resynthesize_common.dart b/pkg/analyzer/test/src/summary/resynthesize_common.dart
index 85bf82785271e..ebb8c92dca4e9 100644
--- a/pkg/analyzer/test/src/summary/resynthesize_common.dart
+++ b/pkg/analyzer/test/src/summary/resynthesize_common.dart
@@ -9547,6 +9547,62 @@ class C {
 ''');
   }
 
+  test_metadata_constructor_call_named_synthetic_ofClassAlias_generic() async {
+    var library = await checkLibrary('''
+class A {
+  const A.named();
+}
+
+mixin B {}
+
+class C<T> = A with B; 
+
+@C.named()
+class D {}
+''');
+    checkElementText(
+        library,
+        r'''
+class A {
+  const A.named();
+}
+class alias C extends A with B {
+  synthetic const C.named() = A.named;
+}
+  typeParameters
+    T
+      bound: null
+      defaultType: dynamic
+class D {
+}
+  metadata
+    Annotation
+      arguments: ArgumentList
+      element: ConstructorMember
+        base: self::@class::C::@constructor::named
+        substitution: {T: dynamic}
+      name: PrefixedIdentifier
+        identifier: SimpleIdentifier
+          staticElement: ConstructorMember
+            base: self::@class::C::@constructor::named
+            substitution: {T: dynamic}
+          staticType: null
+          token: named
+        period: .
+        prefix: SimpleIdentifier
+          staticElement: self::@class::C
+          staticType: null
+          token: C
+        staticElement: ConstructorMember
+          base: self::@class::C::@constructor::named
+          substitution: {T: dynamic}
+        staticType: null
+mixin B on Object {
+}
+''',
+        withFullyResolvedAst: true);
+  }
+
   test_metadata_constructor_call_unnamed() async {
     var library = await checkLibrary('class A { const A(); } @A() class C {}');
     checkElementText(library, r'''
@@ -9574,6 +9630,50 @@ class C {
 ''');
   }
 
+  test_metadata_constructor_call_unnamed_synthetic_ofClassAlias_generic() async {
+    var library = await checkLibrary('''
+class A {
+  const A();
+}
+
+mixin B {}
+
+class C<T> = A with B; 
+
+@C()
+class D {}
+''');
+    checkElementText(
+        library,
+        r'''
+class A {
+  const A();
+}
+class alias C extends A with B {
+  synthetic const C() = A;
+}
+  typeParameters
+    T
+      bound: null
+      defaultType: dynamic
+class D {
+}
+  metadata
+    Annotation
+      arguments: ArgumentList
+      element: ConstructorMember
+        base: self::@class::C::@constructor::•
+        substitution: {T: dynamic}
+      name: SimpleIdentifier
+        staticElement: self::@class::C
+        staticType: null
+        token: C
+mixin B on Object {
+}
+''',
+        withFullyResolvedAst: true);
+  }
+
   test_metadata_constructor_call_with_args() async {
     var library =
         await checkLibrary('class A { const A(x); } @A(null) class C {}');