[DAS] Fixes Go to import on extension getter/setter

Fixes: #61200
Change-Id: I10c64d4aff472c0f219e2b1af79520fbacbb2ea2
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/442460
Auto-Submit: Felipe Morschel <[email protected]>
Reviewed-by: Samuel Rawlins <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Brian Wilkerson <[email protected]>

Author: FMorschel

pkg/analysis_server/lib/src/lsp/handlers/custom/handler_imports.dart

@@ -72,13 +72,14 @@ class ImportsHandler
       if (node is NamedType) {
         prefixName = node.importPrefix?.name.lexeme;
       } else if (node.thisOrAncestorOfType<PrefixedIdentifier>()
-          case PrefixedIdentifier(:var prefix) when prefix != node) {
+          case PrefixedIdentifier(:var prefix)
+          when prefix != node && prefix.element is PrefixElement) {
         prefixName = prefix.name;
       } else if (node is SimpleIdentifier) {
         if (node.parent case MethodInvocation(
           target: SimpleIdentifier target?,
-        )) {
-          prefixName = target.toString();
+        ) when target.element is PrefixElement) {
+          prefixName = target.name;
         }
       }
 

pkg/analysis_server/test/lsp/import_test.dart

@@ -54,6 +54,55 @@ void foo() {
     );
   }
 
+  Future<void> test_extension_getter() async {
+    newFile(join(projectFolderPath, 'lib', 'other.dart'), '''
+extension E on int {
+  int get bar => 42;
+}
+''');
+    await _verifyGoToImports(
+      TestCode.parse('''
+[!import 'other.dart';!]
+
+void f(int i) {
+  i.ba^r;
+}
+'''),
+    );
+  }
+
+  Future<void> test_extension_nestedInvocations() async {
+    newFile(join(projectFolderPath, 'lib', 'other.dart'), '''
+extension E on int {
+  void bar() {}
+}
+''');
+    await _verifyGoToImports(
+      TestCode.parse('''
+[!import 'other.dart';!]
+
+var a = 1.abs().ba^r();
+'''),
+    );
+  }
+
+  Future<void> test_extension_setter() async {
+    newFile(join(projectFolderPath, 'lib', 'other.dart'), '''
+extension E on int {
+  set foo(int _) {}
+}
+''');
+    await _verifyGoToImports(
+      TestCode.parse('''
+[!import 'other.dart';!]
+
+void f(int i) {
+  i.fo^o = 0;
+}
+'''),
+    );
+  }
+
   Future<void> test_function() async {
     await _verifyGoToImports(
       TestCode.parse('''
@@ -413,21 +462,6 @@ var a = A().foo().ba^r();
     );
   }
 
-  Future<void> test_nestedInvocations_extension() async {
-    newFile(join(projectFolderPath, 'lib', 'other.dart'), '''
-extension E on int {
-  void bar() {}
-}
-''');
-    await _verifyGoToImports(
-      TestCode.parse('''
-[!import 'other.dart';!]
-
-var a = 1.abs().ba^r();
-'''),
-    );
-  }
-
   Future<void> test_staticDeclarations() async {
     newFile(join(projectFolderPath, 'lib', 'other.dart'), '''
 class A {