[analysis_server][analyzer] Convert unused declared var patterns to wildcards.

Convert to wildcard variable wasn't triggering for declared variable patterns, this CL makes it so that we do have that fix.

```dart
var (a) = (0); // New fix: convert to wildcard variable
```

Bug: #60082
Change-Id: Ic09219809a9a0fc01b9ab773f58fd815da4a613f
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/411087
Reviewed-by: Phil Quitslund <[email protected]>
Reviewed-by: Brian Wilkerson <[email protected]>
Commit-Queue: Kallen Tu <[email protected]>

Author: kallentu

pkg/analysis_server/lib/src/services/correction/dart/convert_to_wildcard_variable.dart

@@ -6,8 +6,9 @@ import 'package:analysis_server/src/services/correction/fix.dart';
 import 'package:analysis_server/src/services/correction/util.dart';
 import 'package:analysis_server_plugin/edit/dart/correction_producer.dart';
 import 'package:analyzer/dart/analysis/features.dart';
-import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.dart';
 import 'package:analyzer/dart/element/element2.dart';
+import 'package:analyzer/src/dart/ast/ast.dart';
 import 'package:analyzer_plugin/utilities/change_builder/change_builder_core.dart';
 import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
 import 'package:analyzer_plugin/utilities/range_factory.dart';
@@ -32,7 +33,13 @@ class ConvertToWildcardVariable extends ResolvedCorrectionProducer {
     var node = this.node;
 
     if (node is FormalParameter) {
-      await computeFormalParameterConversion(builder, node);
+      await computeVariableConversion(builder, node.name!);
+      return;
+    }
+
+    if (node is DeclaredVariablePatternImpl &&
+        node.fieldNameWithImplicitName == null) {
+      await computeVariableConversion(builder, node.name);
       return;
     }
 
@@ -62,12 +69,12 @@ class ConvertToWildcardVariable extends ResolvedCorrectionProducer {
     });
   }
 
-  Future<void> computeFormalParameterConversion(
+  Future<void> computeVariableConversion(
     ChangeBuilder builder,
-    FormalParameter node,
+    Token name,
   ) async {
     await builder.addDartFileEdit(file, (builder) {
-      builder.addSimpleReplacement(range.token(node.name!), '_');
+      builder.addSimpleReplacement(range.token(name), '_');
     });
   }
 }

pkg/analysis_server/test/src/services/correction/fix/convert_to_wildcard_variable_test.dart

@@ -21,7 +21,7 @@ class ConvertToWildcardVariableTest extends FixProcessorTest {
   @override
   FixKind get kind => DartFixKind.CONVERT_TO_WILDCARD_VARIABLE;
 
-  Future<void> test_convertUnusedLocalVariable() async {
+  Future<void> test_basic() async {
     await resolveTestCode('''
 void f() {
   var x = '';
@@ -34,7 +34,7 @@ void f() {
 ''');
   }
 
-  Future<void> test_convertUnusedLocalVariable_list() async {
+  Future<void> test_list() async {
     await resolveTestCode('''
 void f() {
   int? x, y;
@@ -49,7 +49,7 @@ void f() {
 ''');
   }
 
-  Future<void> test_convertUnusedLocalVariable_listPatternAssignment() async {
+  Future<void> test_listPatternAssignment() async {
     await resolveTestCode('''
 void f() {
   var x = 0;
@@ -64,7 +64,7 @@ void f() {
 ''');
   }
 
-  Future<void> test_convertUnusedLocalVariable_preWildcards() async {
+  Future<void> test_preWildcards() async {
     await resolveTestCode('''
 // @dart = 3.4
 // (pre wildcard-variables)
@@ -76,7 +76,7 @@ void f() {
     await assertNoFix();
   }
 
-  Future<void> test_convertUnusedLocalVariable_recordAssignment() async {
+  Future<void> test_recordAssignment() async {
     await resolveTestCode('''
 void f() {
   var x = 0;
@@ -91,8 +91,7 @@ void f() {
 ''');
   }
 
-  Future<void>
-  test_convertUnusedLocalVariable_recordAssignment_parenthesized() async {
+  Future<void> test_recordAssignment_parenthesized() async {
     await resolveTestCode('''
 void f() {
   var x = 0;
@@ -107,7 +106,62 @@ void f() {
 ''');
   }
 
-  Future<void> test_convertUnusedLocalVariable_reference() async {
+  Future<void> test_recordDestructure() async {
+    await resolveTestCode('''
+void f() {
+  var (a) = (0);
+}
+''');
+    await assertHasFix('''
+void f() {
+  var (_) = (0);
+}
+''');
+  }
+
+  Future<void> test_recordDestructure_implicitName() async {
+    await resolveTestCode('''
+void f() {
+  var (:a) = (a: "x");
+}
+''');
+    await assertNoFix();
+  }
+
+  Future<void> test_recordDestructure_implicitName_multiple() async {
+    await resolveTestCode('''
+void f() {
+  var (:a, _) = (a: "x", 1);
+}
+''');
+    await assertNoFix();
+  }
+
+  Future<void> test_recordDestructure_multiple() async {
+    await resolveTestCode('''
+void f() {
+  var (a, _) = (0, 1);
+}
+''');
+    await assertHasFix('''
+void f() {
+  var (_, _) = (0, 1);
+}
+''');
+  }
+
+  Future<void> test_recordDestructure_preWildcards() async {
+    await resolveTestCode('''
+// @dart = 3.4
+// (pre wildcard-variables)
+void f() {
+  var (a) = (0);
+}
+''');
+    await assertNoFix();
+  }
+
+  Future<void> test_reference() async {
     await resolveTestCode('''
 void f() {
   var x = '';