Remove support for diagnostics related to the required annotation

The annotation has been marked as deprecated for a long time now, and
the annotation hasn't been useful since 2.12.

Change-Id: Ia3bb019ef3fc6b1f9bb406cb268dcc6b78bf1159
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/451403
Commit-Queue: Brian Wilkerson <[email protected]>
Reviewed-by: Konstantin Shcheglov <[email protected]>

Author: bwilkerson

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

@@ -2496,7 +2496,7 @@ LintCode.unnecessary_to_list_in_spreads:
 LintCode.unnecessary_unawaited:
   status: hasFix
 LintCode.unnecessary_underscores:
-  status: hasFix  
+  status: hasFix
 LintCode.unreachable_from_main:
   status: hasFix
 LintCode.unrelated_type_equality_checks_in_expression:
@@ -3673,12 +3673,6 @@ WarningCode.INVALID_OVERRIDE_OF_NON_VIRTUAL_MEMBER:
   status: noFix
 WarningCode.INVALID_REOPEN_ANNOTATION:
   status: hasFix
-WarningCode.INVALID_REQUIRED_NAMED_PARAM:
-  status: hasFix
-WarningCode.INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM:
-  status: hasFix
-WarningCode.INVALID_REQUIRED_POSITIONAL_PARAM:
-  status: hasFix
 WarningCode.INVALID_USE_OF_DO_NOT_SUBMIT_MEMBER:
   status: needsEvaluation
 WarningCode.INVALID_USE_OF_INTERNAL_MEMBER:

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

@@ -1156,9 +1156,6 @@ final _builtInNonLintGenerators = <DiagnosticCode, List<ProducerGenerator>>{
   WarningCode.invalidLiteralAnnotation: [RemoveAnnotation.new],
   WarningCode.invalidNonVirtualAnnotation: [RemoveAnnotation.new],
   WarningCode.invalidReopenAnnotation: [RemoveAnnotation.new],
-  WarningCode.invalidRequiredNamedParam: [RemoveAnnotation.new],
-  WarningCode.invalidRequiredOptionalPositionalParam: [RemoveAnnotation.new],
-  WarningCode.invalidRequiredPositionalParam: [RemoveAnnotation.new],
   WarningCode.invalidVisibilityAnnotation: [RemoveAnnotation.new],
   WarningCode.invalidVisibleForOverridingAnnotation: [RemoveAnnotation.new],
   WarningCode.missingOverrideOfMustBeOverriddenOne: [

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

@@ -290,45 +290,6 @@ base class B extends A {}
 ''');
   }
 
-  Future<void> test_required_namedWithDefault() async {
-    await resolveTestCode('''
-import 'package:meta/meta.dart';
-
-f({@required int x = 0}) {}
-''');
-    await assertHasFix('''
-import 'package:meta/meta.dart';
-
-f({int x = 0}) {}
-''');
-  }
-
-  Future<void> test_required_positional() async {
-    await resolveTestCode('''
-import 'package:meta/meta.dart';
-
-f([@required int? x]) {}
-''');
-    await assertHasFix('''
-import 'package:meta/meta.dart';
-
-f([int? x]) {}
-''');
-  }
-
-  Future<void> test_required_required() async {
-    await resolveTestCode('''
-import 'package:meta/meta.dart';
-
-f(@required int x) {}
-''');
-    await assertHasFix('''
-import 'package:meta/meta.dart';
-
-f(int x) {}
-''');
-  }
-
   Future<void> test_sealed() async {
     await resolveTestCode('''
 import 'package:meta/meta.dart';

pkg/analyzer/lib/src/diagnostic/diagnostic_code_values.g.dart

@@ -1048,9 +1048,6 @@ const List<DiagnosticCode> diagnosticCodeValues = [
   WarningCode.invalidNonVirtualAnnotation,
   WarningCode.invalidOverrideOfNonVirtualMember,
   WarningCode.invalidReopenAnnotation,
-  WarningCode.invalidRequiredNamedParam,
-  WarningCode.invalidRequiredOptionalPositionalParam,
-  WarningCode.invalidRequiredPositionalParam,
   WarningCode.invalidUseOfDoNotSubmitMember,
   WarningCode.invalidUseOfInternalMember,
   WarningCode.invalidUseOfProtectedMember,

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

@@ -507,12 +507,6 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     super.visitFieldFormalParameter(node);
   }
 
-  @override
-  void visitFormalParameterList(FormalParameterList node) {
-    _checkRequiredParameter(node);
-    super.visitFormalParameterList(node);
-  }
-
   @override
   void visitFunctionDeclaration(FunctionDeclaration node) {
     bool wasInDoNotStoreMember = _inDoNotStoreMember;
@@ -1494,39 +1488,6 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     }
   }
 
-  void _checkRequiredParameter(FormalParameterList node) {
-    var requiredParameters = node.parameters.where(
-      (p) => p.declaredFragment?.element.metadata.hasRequired == true,
-    );
-    var nonNamedParamsWithRequired = requiredParameters.where(
-      (p) => p.isPositional,
-    );
-    var namedParamsWithRequiredAndDefault = requiredParameters
-        .where((p) => p.isNamed)
-        .where((p) => p is DefaultFormalParameter && p.defaultValue != null);
-    for (var param in nonNamedParamsWithRequired.where((p) => p.isOptional)) {
-      _diagnosticReporter.atNode(
-        param,
-        WarningCode.invalidRequiredOptionalPositionalParam,
-        arguments: [_formalParameterNameOrEmpty(param)],
-      );
-    }
-    for (var param in nonNamedParamsWithRequired.where((p) => p.isRequired)) {
-      _diagnosticReporter.atNode(
-        param,
-        WarningCode.invalidRequiredPositionalParam,
-        arguments: [_formalParameterNameOrEmpty(param)],
-      );
-    }
-    for (var param in namedParamsWithRequiredAndDefault) {
-      _diagnosticReporter.atNode(
-        param,
-        WarningCode.invalidRequiredNamedParam,
-        arguments: [_formalParameterNameOrEmpty(param)],
-      );
-    }
-  }
-
   /// In "strict-inference" mode, check that each of the [parameterList]' type
   /// is specified.
   ///
@@ -1687,10 +1648,6 @@ class BestPracticesVerifier extends RecursiveAstVisitor<void> {
     return _workspacePackage.contains(library.firstFragment.source);
   }
 
-  static String _formalParameterNameOrEmpty(FormalParameter node) {
-    return node.name?.lexeme ?? '';
-  }
-
   static bool _hasNonVirtualAnnotation(ExecutableElement element) {
     if (element is PropertyAccessorElement && element.isSynthetic) {
       if (element.variable.metadata.hasNonVirtual) {

pkg/analyzer/lib/src/error/codes.g.dart

@@ -11694,57 +11694,6 @@ class WarningCode extends DiagnosticCodeWithExpectedTypes {
         expectedTypes: [],
       );
 
-  /// This warning is generated anywhere where `@required` annotates a named
-  /// parameter with a default value.
-  ///
-  /// Parameters:
-  /// String p0: the name of the member
-  static const WarningTemplate<
-    LocatableDiagnostic Function({required String p0})
-  >
-  invalidRequiredNamedParam = WarningTemplate(
-    'INVALID_REQUIRED_NAMED_PARAM',
-    "The type parameter '{0}' is annotated with @required but only named "
-        "parameters without a default value can be annotated with it.",
-    correctionMessage: "Remove @required.",
-    withArguments: _withArgumentsInvalidRequiredNamedParam,
-    expectedTypes: [ExpectedType.string],
-  );
-
-  /// This warning is generated anywhere where `@required` annotates an optional
-  /// positional parameter.
-  ///
-  /// Parameters:
-  /// String p0: the name of the member
-  static const WarningTemplate<
-    LocatableDiagnostic Function({required String p0})
-  >
-  invalidRequiredOptionalPositionalParam = WarningTemplate(
-    'INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM',
-    "Incorrect use of the annotation @required on the optional positional "
-        "parameter '{0}'. Optional positional parameters cannot be required.",
-    correctionMessage: "Remove @required.",
-    withArguments: _withArgumentsInvalidRequiredOptionalPositionalParam,
-    expectedTypes: [ExpectedType.string],
-  );
-
-  /// This warning is generated anywhere where `@required` annotates a
-  /// non-optional positional parameter.
-  ///
-  /// Parameters:
-  /// String p0: the name of the member
-  static const WarningTemplate<
-    LocatableDiagnostic Function({required String p0})
-  >
-  invalidRequiredPositionalParam = WarningTemplate(
-    'INVALID_REQUIRED_POSITIONAL_PARAM',
-    "Redundant use of the annotation @required on the required positional "
-        "parameter '{0}'.",
-    correctionMessage: "Remove @required.",
-    withArguments: _withArgumentsInvalidRequiredPositionalParam,
-    expectedTypes: [ExpectedType.string],
-  );
-
   /// Parameters:
   /// String p0: the name of the member
   static const WarningTemplate<
@@ -13223,25 +13172,6 @@ class WarningCode extends DiagnosticCodeWithExpectedTypes {
     return LocatableDiagnosticImpl(invalidOverrideOfNonVirtualMember, [p0, p1]);
   }
 
-  static LocatableDiagnostic _withArgumentsInvalidRequiredNamedParam({
-    required String p0,
-  }) {
-    return LocatableDiagnosticImpl(invalidRequiredNamedParam, [p0]);
-  }
-
-  static LocatableDiagnostic
-  _withArgumentsInvalidRequiredOptionalPositionalParam({required String p0}) {
-    return LocatableDiagnosticImpl(invalidRequiredOptionalPositionalParam, [
-      p0,
-    ]);
-  }
-
-  static LocatableDiagnostic _withArgumentsInvalidRequiredPositionalParam({
-    required String p0,
-  }) {
-    return LocatableDiagnosticImpl(invalidRequiredPositionalParam, [p0]);
-  }
-
   static LocatableDiagnostic _withArgumentsInvalidUseOfDoNotSubmitMember({
     required String p0,
   }) {

pkg/analyzer/messages.yaml

@@ -25821,33 +25821,6 @@ WarningCode:
         void m() {}
       }
       ```
-  INVALID_REQUIRED_NAMED_PARAM:
-    parameters:
-      String p0: the name of the member
-    problemMessage: "The type parameter '#p0' is annotated with @required but only named parameters without a default value can be annotated with it."
-    correctionMessage: Remove @required.
-    hasPublishedDocs: false
-    comment: |-
-      This warning is generated anywhere where `@required` annotates a named
-      parameter with a default value.
-  INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM:
-    parameters:
-      String p0: the name of the member
-    problemMessage: "Incorrect use of the annotation @required on the optional positional parameter '#p0'. Optional positional parameters cannot be required."
-    correctionMessage: Remove @required.
-    hasPublishedDocs: false
-    comment: |-
-      This warning is generated anywhere where `@required` annotates an optional
-      positional parameter.
-  INVALID_REQUIRED_POSITIONAL_PARAM:
-    parameters:
-      String p0: the name of the member
-    problemMessage: "Redundant use of the annotation @required on the required positional parameter '#p0'."
-    correctionMessage: Remove @required.
-    hasPublishedDocs: false
-    comment: |-
-      This warning is generated anywhere where `@required` annotates a
-      non-optional positional parameter.
   INVALID_USE_OF_DO_NOT_SUBMIT_MEMBER:
     parameters:
       String p0: the name of the member