CQ. Fix for NPE in RequiredParametersVerifier.

Saw a crash in logs: _TypeError: Null check operator used on a null value at RequiredParametersVerifier._check (required_parameters_verifier.dart:147) at RequiredParametersVerifier.visitInstanceCreationExpression (required_parameters_verifier.dart:83) at ErrorVerifier.visitInstanceCreationExpression (error_verifier.dart:1153) at InstanceCreationExpressionImpl.accept (ast.dart:13711) at NamedExpressionImpl.visitChildren (ast.dart:16661) at RecursiveAstVisitor.visitNamedExpression (visitor.g.dart:1345) Change-Id: Ia78df6ee7179f511d869ebb4706da5cda6a0ea29 Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/456109 Commit-Queue: Konstantin Shcheglov <scheglov@google.com> Reviewed-by: Johnni Winther <johnniwinther@google.com>

Author: scheglov

pkg/analyzer/lib/src/error/required_parameters_verifier.dart

@@ -144,7 +144,11 @@ class RequiredParametersVerifier extends SimpleAstVisitor<void> {
 
  for (FormalParameterElement parameter in parameters) {
  if (parameter.isRequiredNamed) {
- String parameterName = parameter.name!;
+ var parameterName = parameter.name;
+ if (parameterName == null) {
+ continue;
+ }
+
  if (!_containsNamedExpression(
  enclosingConstructor,
  arguments,

pkg/analyzer/test/src/diagnostics/missing_required_param_test.dart

@@ -2,6 +2,7 @@
 // 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:analyzer/src/dart/error/syntactic_errors.dart';
 import 'package:analyzer/src/error/codes.dart';
 import 'package:test_reflective_loader/test_reflective_loader.dart';
 
@@ -91,6 +92,29 @@ main() {
 ''');
  }
 
+ test_constructor_fieldFormal_missingName() async {
+ await assertErrorsInCode(
+ r'''
+class A {
+ A({required this.})
+}
+
+void f() {
+ A();
+}
+''',
+ [
+ error(
+ CompileTimeErrorCode.initializingFormalForNonExistentField,
+ 15,
+ 14,
+ ),
+ error(ParserErrorCode.missingIdentifier, 29, 1),
+ error(ParserErrorCode.missingFunctionBody, 32, 1),
+ ],
+ );
+ }
+
  test_constructor_missingArgument() async {
  await assertErrorsInCode(
  r'''