Augment. Fixes for navigation for constructor annotations.

...and for import prefixes in augmentations.

Change-Id: I4c2f358d5bd1819c8691990a0b86a37d04449213
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/360505
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>

pkg/analysis_server/test/analysis/notification_navigation_test.dart

@@ -463,6 +463,44 @@ void f() {
     assertHasTarget('foo', targetFile: aFile);
   }
 
+  Future<void>
+      test_class_constructor_annotationConstructor_importPrefix() async {
+    final a = newFile('$testPackageLibPath/a.dart', r'''
+class A {
+  const A();
+  const A.named();
+}
+''');
+
+    addTestFile('''
+library augment 'b.dart';
+import 'a.dart' as prefix;
+
+class B {
+  @prefix.A()
+  @prefix.A.named()
+  B().foo();
+}
+''');
+
+    await prepareNavigation();
+
+    assertHasRegion('prefix.A()');
+    assertHasTarget('prefix;');
+
+    assertHasRegion('A()');
+    assertHasTarget('A();', targetFile: a);
+
+    assertHasRegion('prefix.A.named()');
+    assertHasTarget('prefix;');
+
+    assertHasRegion('A.named()');
+    assertHasTarget('named()', targetFile: a);
+
+    assertHasRegion('named()');
+    assertHasTarget('named()', targetFile: a);
+  }
+
   Future<void> test_class_constructor_named() async {
     addTestFile('''
 class A {
@@ -1381,6 +1419,35 @@ library my.lib;
     assertHasTargetString('my.lib');
   }
 
+  Future<void>
+      test_libraryAugmentation_topLevelFunction_annotationConstructor_importPrefix() async {
+    final a = newFile('$testPackageLibPath/a.dart', r'''
+class A {
+  const A();
+}
+''');
+
+    newFile('$testPackageLibPath/b.dart', r'''
+import augment 'test.dart';
+''');
+
+    addTestFile('''
+library augment 'b.dart';
+import 'a.dart' as prefix;
+
+@prefix.A()
+external B().foo();
+''');
+
+    await prepareNavigation();
+
+    assertHasRegion('prefix.A()');
+    assertHasTarget('prefix;');
+
+    assertHasRegion('A()');
+    assertHasTarget('A();', targetFile: a);
+  }
+
   Future<void> test_multiplyDefinedElement() async {
     newFile('$testPackageLibPath/libA.dart', 'library A; int TEST = 1;');
     newFile('$testPackageLibPath/libB.dart', 'library B; int TEST = 2;');

pkg/analyzer_plugin/lib/utilities/analyzer_converter.dart

@@ -321,10 +321,11 @@ extension ElementExtensions on analyzer.Element? {
     if (currentElement is analyzer.CompilationUnitElement) {
       return currentElement;
     }
-    if (currentElement?.enclosingElement is analyzer.LibraryElement) {
+    if (currentElement?.enclosingElement
+        is analyzer.LibraryOrAugmentationElement) {
       currentElement = currentElement?.enclosingElement;
     }
-    if (currentElement is analyzer.LibraryElement) {
+    if (currentElement is analyzer.LibraryOrAugmentationElement) {
       return currentElement.definingCompilationUnit;
     }
     for (;

pkg/analyzer_plugin/lib/utilities/navigation/navigation_dart.dart

@@ -293,6 +293,8 @@ class _DartNavigationComputerVisitor extends RecursiveAstVisitor<void> {
 
   @override
   void visitConstructorDeclaration(ConstructorDeclaration node) {
+    node.metadata.accept(this);
+
     // For a default constructor, override the class name to be the declaration
     // itself rather than linking to the class.
     var nameToken = node.name;
@@ -302,6 +304,7 @@ class _DartNavigationComputerVisitor extends RecursiveAstVisitor<void> {
       node.returnType.accept(this);
       computer._addRegionForToken(nameToken, node.declaredElement);
     }
+
     node.parameters.accept(this);
     node.initializers.accept(this);
     node.redirectedConstructor?.accept(this);