Issue 51931. Fix for LATE_PATTERN_VARIABLE_DECLARATION.

Bug: #51931
Change-Id: I2b3c42389a5184086e66a1fc35c045d2581a2d8b
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/293004
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Konstantin Shcheglov <scheglov@google.com>

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

@@ -0,0 +1,76 @@
+// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/dart/abstract_producer.dart';
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer/dart/ast/ast.dart';
+import 'package:analyzer/dart/ast/token.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';
+
+class RemoveLate extends CorrectionProducer {
+  @override
+  bool get canBeAppliedInBulk => true;
+
+  @override
+  bool get canBeAppliedToFile => true;
+
+  @override
+  FixKind get fixKind => DartFixKind.REMOVE_LATE;
+
+  @override
+  FixKind get multiFixKind => DartFixKind.REMOVE_LATE_MULTI;
+
+  _LateKeywordLocation? get _lateKeywordLocation {
+    final node = this.node;
+    if (node is Block) {
+      // The `late` token does not belong any node, so when we look for a
+      // node that covers it, we find the enclosing `Block`. So, we iterate
+      // over statements to find the actual declaration statement.
+      for (final statement in node.statements) {
+        if (statement is PatternVariableDeclarationStatement) {
+          final beginToken = statement.beginToken;
+          final lateKeyword = beginToken.previous;
+          if (lateKeyword != null &&
+              lateKeyword.keyword == Keyword.LATE &&
+              lateKeyword.offset == selectionOffset &&
+              lateKeyword.end == selectionEnd) {
+            return _LateKeywordLocation(
+              lateKeyword: lateKeyword,
+              nextToken: beginToken,
+            );
+          }
+        }
+      }
+    }
+
+    return null;
+  }
+
+  @override
+  Future<void> compute(ChangeBuilder builder) async {
+    final location = _lateKeywordLocation;
+    if (location != null) {
+      await builder.addDartFileEdit(file, (builder) {
+        builder.addDeletion(
+          range.startStart(
+            location.lateKeyword,
+            location.nextToken,
+          ),
+        );
+      });
+    }
+  }
+}
+
+class _LateKeywordLocation {
+  final Token lateKeyword;
+  final Token nextToken;
+
+  _LateKeywordLocation({
+    required this.lateKeyword,
+    required this.nextToken,
+  });
+}

pkg/analysis_server/lib/src/services/correction/error_fix_status.yaml

@@ -2528,7 +2528,7 @@ ParserErrorCode.INVALID_UNICODE_ESCAPE_U_STARTED:
 ParserErrorCode.INVALID_USE_OF_COVARIANT_IN_EXTENSION:
   status: needsEvaluation
 ParserErrorCode.LATE_PATTERN_VARIABLE_DECLARATION:
-  status: needsEvaluation
+  status: hasFix
 ParserErrorCode.LIBRARY_DIRECTIVE_NOT_FIRST:
   status: needsEvaluation
 ParserErrorCode.LITERAL_WITH_CLASS_AND_NEW:

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

@@ -1116,6 +1116,16 @@ class DartFixKind {
     DartFixKindPriority.IN_FILE,
     'Remove unnecessary interpolation braces everywhere in file',
   );
+  static const REMOVE_LATE = FixKind(
+    'dart.fix.remove.late',
+    DartFixKindPriority.DEFAULT,
+    "Remove the 'late' keyword",
+  );
+  static const REMOVE_LATE_MULTI = FixKind(
+    'dart.fix.remove.late.multi',
+    DartFixKindPriority.DEFAULT,
+    "Remove the 'late' keyword everywhere in file",
+  );
   static const REMOVE_LEADING_UNDERSCORE = FixKind(
     'dart.fix.remove.leadingUnderscore',
     DartFixKindPriority.DEFAULT,

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

@@ -137,6 +137,7 @@ import 'package:analysis_server/src/services/correction/dart/remove_if_null_oper
 import 'package:analysis_server/src/services/correction/dart/remove_initializer.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_interpolation_braces.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_invocation.dart';
+import 'package:analysis_server/src/services/correction/dart/remove_late.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_leading_underscore.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_method_declaration.dart';
 import 'package:analysis_server/src/services/correction/dart/remove_name_from_combinator.dart';
@@ -1418,6 +1419,9 @@ class FixProcessor extends BaseProcessor {
     ParserErrorCode.INVALID_INSIDE_UNARY_PATTERN: [
       SurroundWithParentheses.new,
     ],
+    ParserErrorCode.LATE_PATTERN_VARIABLE_DECLARATION: [
+      RemoveLate.new,
+    ],
     ParserErrorCode.MISSING_CONST_FINAL_VAR_OR_TYPE: [
       AddTypeAnnotation.new,
     ],

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

@@ -0,0 +1,53 @@
+// Copyright (c) 2023, the Dart project authors. Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+import 'package:analysis_server/src/services/correction/fix.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'fix_processor.dart';
+
+void main() {
+  defineReflectiveSuite(() {
+    defineReflectiveTests(RemoveLateBulkTest);
+    defineReflectiveTests(RemoveLateTest);
+  });
+}
+
+@reflectiveTest
+class RemoveLateBulkTest extends BulkFixProcessorTest {
+  Future<void> test_singleFile() async {
+    await resolveTestCode('''
+void f(Object? x) {
+  late var (_) = x;
+  late var (_) = x;
+}
+''');
+    await assertHasFix('''
+void f(Object? x) {
+  var (_) = x;
+  var (_) = x;
+}
+''');
+  }
+}
+
+@reflectiveTest
+class RemoveLateTest extends FixProcessorTest {
+  @override
+  FixKind get kind => DartFixKind.REMOVE_LATE;
+
+  Future<void> test_it() async {
+    await resolveTestCode('''
+void f(Object? x) {
+  late var (_) = x;
+}
+''');
+    await assertHasFix('''
+void f(Object? x) {
+  var (_) = x;
+}
+''');
+  }
+}

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

@@ -166,6 +166,7 @@ import 'remove_if_null_operator_test.dart' as remove_if_null_operator;
 import 'remove_initializer_test.dart' as remove_initializer;
 import 'remove_interpolation_braces_test.dart' as remove_interpolation_braces;
 import 'remove_invocation_test.dart' as remove_invocation;
+import 'remove_late_test.dart' as remove_late;
 import 'remove_leading_underscore_test.dart' as remove_leading_underscore;
 import 'remove_method_declaration_test.dart' as remove_method_declaration;
 import 'remove_name_from_combinator_test.dart' as remove_name_from_combinator;
@@ -408,6 +409,7 @@ void main() {
     remove_initializer.main();
     remove_interpolation_braces.main();
     remove_invocation.main();
+    remove_late.main();
     remove_leading_underscore.main();
     remove_method_declaration.main();
     remove_name_from_combinator.main();