| // Copyright (c) 2019, 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 'dart:collection'; |
| |
| import 'package:analyzer/dart/analysis/features.dart'; |
| import 'package:analyzer/dart/ast/syntactic_entity.dart'; |
| import 'package:analyzer/dart/ast/token.dart'; |
| import 'package:analyzer/dart/ast/visitor.dart'; |
| import 'package:analyzer/dart/constant/value.dart'; |
| import 'package:analyzer/dart/element/element.dart'; |
| import 'package:analyzer/dart/element/type.dart'; |
| import 'package:analyzer/error/error.dart'; |
| import 'package:analyzer/error/listener.dart'; |
| import 'package:analyzer/src/dart/ast/ast.dart'; |
| import 'package:analyzer/src/dart/ast/extensions.dart'; |
| import 'package:analyzer/src/dart/element/element.dart'; |
| import 'package:analyzer/src/dart/element/extensions.dart'; |
| import 'package:analyzer/src/dart/element/inheritance_manager3.dart'; |
| import 'package:analyzer/src/dart/element/member.dart' show ExecutableMember; |
| import 'package:analyzer/src/dart/element/type.dart'; |
| import 'package:analyzer/src/dart/element/type_provider.dart'; |
| import 'package:analyzer/src/dart/element/type_system.dart'; |
| import 'package:analyzer/src/dart/resolver/scope.dart'; |
| import 'package:analyzer/src/error/annotation_verifier.dart'; |
| import 'package:analyzer/src/error/codes.dart'; |
| import 'package:analyzer/src/error/deprecated_member_use_verifier.dart'; |
| import 'package:analyzer/src/error/doc_comment_verifier.dart'; |
| import 'package:analyzer/src/error/error_handler_verifier.dart'; |
| import 'package:analyzer/src/error/must_call_super_verifier.dart'; |
| import 'package:analyzer/src/error/null_safe_api_verifier.dart'; |
| import 'package:analyzer/src/generated/engine.dart'; |
| import 'package:analyzer/src/lint/linter.dart'; |
| import 'package:analyzer/src/utilities/extensions/ast.dart'; |
| import 'package:analyzer/src/utilities/extensions/element.dart'; |
| import 'package:analyzer/src/workspace/workspace.dart'; |
| import 'package:meta/meta.dart'; |
| |
| /// Instances of the class `BestPracticesVerifier` traverse an AST structure |
| /// looking for violations of Dart best practices. |
| class BestPracticesVerifier extends RecursiveAstVisitor<void> { |
| /// The class containing the AST nodes being visited, or `null` if we are not |
| /// in the scope of a class. |
| InterfaceElement? _enclosingClass; |
| |
| /// A flag indicating whether a surrounding member is annotated as |
| /// `@doNotStore`. |
| bool _inDoNotStoreMember = false; |
| |
| /// The error reporter by which errors will be reported. |
| final ErrorReporter _errorReporter; |
| |
| /// The type [Null]. |
| final InterfaceType _nullType; |
| |
| /// The type system primitives. |
| final TypeSystemImpl _typeSystem; |
| |
| /// The inheritance manager to access interface type hierarchy. |
| final InheritanceManager3 _inheritanceManager; |
| |
| /// The current library. |
| final LibraryElement _currentLibrary; |
| |
| final AnnotationVerifier _annotationVerifier; |
| |
| final DeprecatedMemberUseVerifier _deprecatedVerifier; |
| |
| final ErrorHandlerVerifier _errorHandlerVerifier; |
| |
| final _InvalidAccessVerifier _invalidAccessVerifier; |
| |
| final MustCallSuperVerifier _mustCallSuperVerifier; |
| |
| final NullSafeApiVerifier _nullSafeApiVerifier; |
| |
| late final DocCommentVerifier _docCommentVerifier = |
| DocCommentVerifier(_errorReporter); |
| |
| /// The [WorkspacePackage] in which [_currentLibrary] is declared. |
| final WorkspacePackage? _workspacePackage; |
| |
| /// True if inference failures should be reported, otherwise false. |
| final bool _strictInference; |
| |
| /// Whether [_currentLibrary] is part of its containing package's public API. |
| late final bool _inPackagePublicApi = _workspacePackage != null && |
| _workspacePackage.sourceIsInPublicApi(_currentLibrary.source); |
| |
| BestPracticesVerifier( |
| this._errorReporter, |
| TypeProviderImpl typeProvider, |
| this._currentLibrary, |
| CompilationUnit unit, { |
| required TypeSystemImpl typeSystem, |
| required InheritanceManager3 inheritanceManager, |
| required AnalysisOptions analysisOptions, |
| required WorkspacePackage? workspacePackage, |
| }) : _nullType = typeProvider.nullType, |
| _typeSystem = typeSystem, |
| _strictInference = |
| (analysisOptions as AnalysisOptionsImpl).strictInference, |
| _inheritanceManager = inheritanceManager, |
| _annotationVerifier = AnnotationVerifier( |
| _errorReporter, _currentLibrary, workspacePackage), |
| _deprecatedVerifier = DeprecatedMemberUseVerifier( |
| workspacePackage, _errorReporter, |
| strictCasts: analysisOptions.strictCasts), |
| _errorHandlerVerifier = ErrorHandlerVerifier( |
| _errorReporter, typeProvider, typeSystem, |
| strictCasts: analysisOptions.strictCasts), |
| _invalidAccessVerifier = _InvalidAccessVerifier( |
| _errorReporter, unit, _currentLibrary, workspacePackage), |
| _mustCallSuperVerifier = MustCallSuperVerifier(_errorReporter), |
| _nullSafeApiVerifier = NullSafeApiVerifier(_errorReporter, typeSystem), |
| _workspacePackage = workspacePackage { |
| _deprecatedVerifier.pushInDeprecatedValue(_currentLibrary.hasDeprecated); |
| _inDoNotStoreMember = _currentLibrary.hasDoNotStore; |
| } |
| |
| @override |
| void visitAnnotation(Annotation node) { |
| _annotationVerifier.checkAnnotation(node); |
| super.visitAnnotation(node); |
| } |
| |
| @override |
| void visitArgumentList(ArgumentList node) { |
| _invalidAccessVerifier._checkForInvalidDoNotSubmitParameter(node); |
| super.visitArgumentList(node); |
| } |
| |
| @override |
| void visitAsExpression(AsExpression node) { |
| if (isUnnecessaryCast(node, _typeSystem)) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.UNNECESSARY_CAST, |
| ); |
| } |
| var type = node.type.type; |
| if (type != null && |
| _typeSystem.isNonNullable(type) && |
| node.expression.typeOrThrow.isDartCoreNull) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.CAST_FROM_NULL_ALWAYS_FAILS, |
| ); |
| } |
| super.visitAsExpression(node); |
| } |
| |
| @override |
| void visitAssignmentExpression(AssignmentExpression node) { |
| _deprecatedVerifier.assignmentExpression(node); |
| super.visitAssignmentExpression(node); |
| } |
| |
| @override |
| void visitBinaryExpression(BinaryExpression node) { |
| _checkForDivisionOptimizationHint(node); |
| _deprecatedVerifier.binaryExpression(node); |
| _checkForInvariantNanComparison(node); |
| _checkForInvariantNullComparison(node); |
| _invalidAccessVerifier.verifyBinary(node); |
| super.visitBinaryExpression(node); |
| } |
| |
| @override |
| void visitCastPattern(CastPattern node) { |
| var type = node.type.type; |
| var matchedValueType = node.matchedValueType; |
| if (type != null && |
| _typeSystem.isNonNullable(type) && |
| matchedValueType != null && |
| matchedValueType.isDartCoreNull) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.CAST_FROM_NULL_ALWAYS_FAILS, |
| ); |
| } |
| super.visitCastPattern(node); |
| } |
| |
| @override |
| void visitCatchClause(CatchClause node) { |
| super.visitCatchClause(node); |
| _checkForNullableTypeInCatchClause(node); |
| } |
| |
| @override |
| void visitClassDeclaration(covariant ClassDeclarationImpl node) { |
| var element = node.declaredElement!; |
| if (element.isAugmentation) { |
| return; |
| } |
| |
| _enclosingClass = element; |
| _invalidAccessVerifier._enclosingClass = element; |
| |
| bool wasInDoNotStoreMember = _inDoNotStoreMember; |
| _deprecatedVerifier.pushInDeprecatedValue(element.hasDeprecated); |
| if (element.hasDoNotStore) { |
| _inDoNotStoreMember = true; |
| } |
| |
| try { |
| _checkForImmutable(node); |
| _checkForInvalidSealedSuperclass(node); |
| super.visitClassDeclaration(node); |
| } finally { |
| _enclosingClass = null; |
| _invalidAccessVerifier._enclosingClass = null; |
| _deprecatedVerifier.popInDeprecated(); |
| _inDoNotStoreMember = wasInDoNotStoreMember; |
| } |
| } |
| |
| @override |
| void visitClassTypeAlias(ClassTypeAlias node) { |
| _checkForImmutable(node); |
| _checkForInvalidSealedSuperclass(node); |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitClassTypeAlias(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitComment(Comment node) { |
| for (var docImport in node.docImports) { |
| _docCommentVerifier.docImport(docImport); |
| } |
| for (var docDirective in node.docDirectives) { |
| _docCommentVerifier.docDirective(docDirective); |
| } |
| super.visitComment(node); |
| } |
| |
| @override |
| void visitCommentReference(CommentReference node) { |
| var newKeyword = node.newKeyword; |
| if (newKeyword != null && |
| _currentLibrary.featureSet.isEnabled(Feature.constructor_tearoffs)) { |
| _errorReporter.atToken( |
| newKeyword, |
| WarningCode.DEPRECATED_NEW_IN_COMMENT_REFERENCE, |
| ); |
| } |
| super.visitCommentReference(node); |
| } |
| |
| @override |
| void visitConstantPattern(ConstantPattern node) { |
| if (node.expression.isDoubleNan) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.UNNECESSARY_NAN_COMPARISON_FALSE, |
| ); |
| } |
| super.visitConstantPattern(node); |
| } |
| |
| @override |
| void visitConstructorDeclaration(ConstructorDeclaration node) { |
| var element = node.declaredElement as ConstructorElementImpl; |
| _checkStrictInferenceInParameters(node.parameters, |
| body: node.body, initializers: node.initializers); |
| _deprecatedVerifier.pushInDeprecatedValue(element.hasDeprecated); |
| try { |
| super.visitConstructorDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitConstructorName(ConstructorName node) { |
| _deprecatedVerifier.constructorName(node); |
| super.visitConstructorName(node); |
| } |
| |
| @override |
| void visitDefaultFormalParameter(DefaultFormalParameter node) { |
| var separator = node.separator; |
| if (node.isNamed && |
| separator != null && |
| separator.type == TokenType.COLON) { |
| // This is a warning in code whose language version is < 3.0, but an error |
| // in code whose language version is >= 3.0. |
| if (_currentLibrary.languageVersion.effective.major < 3) { |
| _errorReporter.atToken( |
| separator, |
| HintCode.DEPRECATED_COLON_FOR_DEFAULT_VALUE, |
| ); |
| } else { |
| _errorReporter.atToken( |
| separator, |
| CompileTimeErrorCode.OBSOLETE_COLON_FOR_DEFAULT_VALUE, |
| ); |
| } |
| } |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitDefaultFormalParameter(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitEnumDeclaration(EnumDeclaration node) { |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitEnumDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitExportDirective(ExportDirective node) { |
| _deprecatedVerifier.exportDirective(node); |
| _checkForInternalExport(node); |
| super.visitExportDirective(node); |
| } |
| |
| @override |
| void visitExpressionFunctionBody(ExpressionFunctionBody node) { |
| if (!_invalidAccessVerifier._inTestDirectory) { |
| _checkForReturnOfDoNotStore(node.expression); |
| } |
| super.visitExpressionFunctionBody(node); |
| } |
| |
| @override |
| void visitExtensionDeclaration(ExtensionDeclaration node) { |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitExtensionDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitExtensionOverride(ExtensionOverride node) { |
| _deprecatedVerifier.extensionOverride(node); |
| super.visitExtensionOverride(node); |
| } |
| |
| @override |
| void visitExtensionTypeDeclaration(ExtensionTypeDeclaration node) { |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitExtensionTypeDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitFieldDeclaration(FieldDeclaration node) { |
| _deprecatedVerifier.pushInDeprecatedMetadata(node.metadata); |
| |
| try { |
| super.visitFieldDeclaration(node); |
| for (var field in node.fields.variables) { |
| ExecutableElement? getOverriddenPropertyAccessor() { |
| var element = field.declaredElement; |
| if (element is PropertyAccessorElement || element is FieldElement) { |
| Name name = Name(_currentLibrary.source.uri, element!.name); |
| var enclosingElement = element.enclosingElement!; |
| var enclosingDeclaration = enclosingElement is InstanceElement |
| ? enclosingElement.augmented.declaration |
| : enclosingElement; |
| if (enclosingDeclaration is InterfaceElement) { |
| var overridden = _inheritanceManager |
| .getMember2(enclosingDeclaration, name, forSuper: true); |
| // Check for a setter. |
| if (overridden == null) { |
| Name setterName = |
| Name(_currentLibrary.source.uri, '${element.name}='); |
| overridden = _inheritanceManager.getMember2( |
| enclosingDeclaration, setterName, |
| forSuper: true); |
| } |
| return overridden; |
| } |
| } |
| return null; |
| } |
| |
| var overriddenElement = getOverriddenPropertyAccessor(); |
| if (overriddenElement != null && |
| _hasNonVirtualAnnotation(overriddenElement)) { |
| // Overridden members are always inside classes or mixins, which are |
| // always named, so we can safely assume |
| // `overriddenElement.enclosingElement3.name` is non-`null`. |
| _errorReporter.atToken( |
| field.name, |
| WarningCode.INVALID_OVERRIDE_OF_NON_VIRTUAL_MEMBER, |
| arguments: [ |
| field.name.lexeme, |
| overriddenElement.enclosingElement.displayName |
| ], |
| ); |
| } |
| if (!_invalidAccessVerifier._inTestDirectory) { |
| _checkForAssignmentOfDoNotStore(field.initializer); |
| } |
| } |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitFieldFormalParameter(FieldFormalParameter node) { |
| _checkFinalParameter(node, node.keyword); |
| super.visitFieldFormalParameter(node); |
| } |
| |
| @override |
| void visitFormalParameterList(FormalParameterList node) { |
| _checkRequiredParameter(node); |
| super.visitFormalParameterList(node); |
| } |
| |
| @override |
| void visitFunctionDeclaration(FunctionDeclaration node) { |
| bool wasInDoNotStoreMember = _inDoNotStoreMember; |
| ExecutableElement element = node.declaredElement!; |
| _deprecatedVerifier.pushInDeprecatedValue(element.hasDeprecated); |
| if (element.hasDoNotStore) { |
| _inDoNotStoreMember = true; |
| } |
| try { |
| // Return types are inferred only on non-recursive local functions. |
| if (node.parent is CompilationUnit && !node.isSetter) { |
| _checkStrictInferenceReturnType( |
| node.returnType, node, node.name.lexeme); |
| } |
| _checkStrictInferenceInParameters(node.functionExpression.parameters, |
| body: node.functionExpression.body); |
| super.visitFunctionDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| _inDoNotStoreMember = wasInDoNotStoreMember; |
| } |
| } |
| |
| @override |
| void visitFunctionDeclarationStatement(FunctionDeclarationStatement node) { |
| // TODO(srawlins): Check strict-inference return type on recursive |
| // local functions. |
| super.visitFunctionDeclarationStatement(node); |
| } |
| |
| @override |
| void visitFunctionExpression(FunctionExpression node) { |
| var body = node.body; |
| if (!(node as FunctionExpressionImpl).wasFunctionTypeSupplied) { |
| _checkStrictInferenceInParameters(node.parameters, body: node.body); |
| } |
| _checkForUnnecessarySetLiteral(body, node); |
| super.visitFunctionExpression(node); |
| } |
| |
| @override |
| void visitFunctionExpressionInvocation(FunctionExpressionInvocation node) { |
| _deprecatedVerifier.functionExpressionInvocation(node); |
| super.visitFunctionExpressionInvocation(node); |
| } |
| |
| @override |
| void visitFunctionTypeAlias(FunctionTypeAlias node) { |
| _checkStrictInferenceReturnType(node.returnType, node, node.name.lexeme); |
| _checkStrictInferenceInParameters(node.parameters); |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitFunctionTypeAlias(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitFunctionTypedFormalParameter(FunctionTypedFormalParameter node) { |
| _checkStrictInferenceReturnType(node.returnType, node, node.name.lexeme); |
| _checkStrictInferenceInParameters(node.parameters); |
| super.visitFunctionTypedFormalParameter(node); |
| } |
| |
| @override |
| void visitGenericFunctionType(GenericFunctionType node) { |
| // GenericTypeAlias is handled in [visitGenericTypeAlias], where a proper |
| // name can be reported in any message. |
| if (node.parent is! GenericTypeAlias) { |
| _checkStrictInferenceReturnType(node.returnType, node, node.toString()); |
| } |
| super.visitGenericFunctionType(node); |
| } |
| |
| @override |
| void visitGenericTypeAlias(GenericTypeAlias node) { |
| if (node.functionType != null) { |
| _checkStrictInferenceReturnType( |
| node.functionType!.returnType, node, node.name.lexeme); |
| } |
| _deprecatedVerifier |
| .pushInDeprecatedValue(node.declaredElement!.hasDeprecated); |
| |
| try { |
| super.visitGenericTypeAlias(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitImportDirective(ImportDirective node) { |
| _deprecatedVerifier.importDirective(node); |
| var importElement = node.element; |
| if (importElement != null && |
| importElement.prefix is DeferredImportElementPrefix) { |
| _checkForLoadLibraryFunction(node, importElement); |
| } |
| _invalidAccessVerifier.verifyImport(node); |
| super.visitImportDirective(node); |
| } |
| |
| @override |
| void visitIndexExpression(IndexExpression node) { |
| _deprecatedVerifier.indexExpression(node); |
| super.visitIndexExpression(node); |
| } |
| |
| @override |
| void visitInstanceCreationExpression(InstanceCreationExpression node) { |
| _deprecatedVerifier.instanceCreationExpression(node); |
| _nullSafeApiVerifier.instanceCreation(node); |
| _checkForLiteralConstructorUse(node); |
| super.visitInstanceCreationExpression(node); |
| } |
| |
| @override |
| void visitIsExpression(IsExpression node) { |
| _checkAllTypeChecks(node); |
| super.visitIsExpression(node); |
| } |
| |
| @override |
| void visitMethodDeclaration(MethodDeclaration node) { |
| bool wasInDoNotStoreMember = _inDoNotStoreMember; |
| var element = node.declaredElement!; |
| var enclosingElement = element.enclosingElement; |
| var enclosingDeclaration = enclosingElement is InstanceElement |
| ? enclosingElement.augmented.declaration |
| : enclosingElement; |
| |
| _deprecatedVerifier.pushInDeprecatedValue(element.hasDeprecated); |
| if (element.hasDoNotStore) { |
| _inDoNotStoreMember = true; |
| } |
| try { |
| _mustCallSuperVerifier.checkMethodDeclaration(node); |
| _checkForUnnecessaryNoSuchMethod(node); |
| _checkForNullableEqualsParameterType(node); |
| |
| var name = Name(_currentLibrary.source.uri, element.name); |
| var elementIsOverride = element is ClassMemberElement && |
| enclosingDeclaration is InterfaceElement |
| ? _inheritanceManager.getOverridden2(enclosingDeclaration, name) != |
| null |
| : false; |
| |
| if (!node.isSetter && !elementIsOverride) { |
| _checkStrictInferenceReturnType( |
| node.returnType, node, node.name.lexeme); |
| } |
| if (!elementIsOverride) { |
| _checkStrictInferenceInParameters(node.parameters, body: node.body); |
| } |
| |
| var overriddenElement = enclosingDeclaration is InterfaceElement |
| ? _inheritanceManager.getMember2(enclosingDeclaration, name, |
| forSuper: true) |
| : null; |
| |
| if (overriddenElement != null && |
| _hasNonVirtualAnnotation(overriddenElement)) { |
| // Overridden members are always inside classes or mixins, which are |
| // always named, so we can safely assume |
| // `overriddenElement.enclosingElement3.name` is non-`null`. |
| _errorReporter.atToken( |
| node.name, |
| WarningCode.INVALID_OVERRIDE_OF_NON_VIRTUAL_MEMBER, |
| arguments: [ |
| node.name.lexeme, |
| overriddenElement.enclosingElement.displayName |
| ], |
| ); |
| } |
| |
| super.visitMethodDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| _inDoNotStoreMember = wasInDoNotStoreMember; |
| } |
| } |
| |
| @override |
| void visitMethodInvocation(MethodInvocation node) { |
| _deprecatedVerifier.methodInvocation(node); |
| _errorHandlerVerifier.verifyMethodInvocation(node); |
| _nullSafeApiVerifier.methodInvocation(node); |
| super.visitMethodInvocation(node); |
| } |
| |
| @override |
| void visitMixinDeclaration(covariant MixinDeclarationImpl node) { |
| var element = node.declaredElement!; |
| if (element.isAugmentation) { |
| return; |
| } |
| |
| _enclosingClass = element; |
| _invalidAccessVerifier._enclosingClass = _enclosingClass; |
| |
| _deprecatedVerifier.pushInDeprecatedValue(element.hasDeprecated); |
| |
| try { |
| _checkForImmutable(node); |
| _checkForInvalidSealedSuperclass(node); |
| super.visitMixinDeclaration(node); |
| } finally { |
| _enclosingClass = null; |
| _invalidAccessVerifier._enclosingClass = null; |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| @override |
| void visitNamedType(NamedType node) { |
| _deprecatedVerifier.namedType(node); |
| _invalidAccessVerifier.verifyNamedType(node); |
| var question = node.question; |
| if (question != null) { |
| var type = node.typeOrThrow; |
| // Only report non-aliased, non-user-defined `Null?` and `dynamic?`. Do |
| // not report synthetic `dynamic` in place of an unresolved type. |
| if ((type is InterfaceType && type.element == _nullType.element || |
| (type is DynamicType && node.name2.lexeme == 'dynamic')) && |
| type.alias == null) { |
| _errorReporter.atToken( |
| question, |
| WarningCode.UNNECESSARY_QUESTION_MARK, |
| arguments: [node.qualifiedName], |
| ); |
| } |
| } |
| super.visitNamedType(node); |
| } |
| |
| @override |
| void visitPatternField(PatternField node) { |
| _deprecatedVerifier.patternField(node); |
| _invalidAccessVerifier.verifyPatternField(node as PatternFieldImpl); |
| super.visitPatternField(node); |
| } |
| |
| @override |
| void visitPostfixExpression(PostfixExpression node) { |
| _deprecatedVerifier.postfixExpression(node); |
| if (node.operator.type == TokenType.BANG && |
| node.operand.typeOrThrow.isDartCoreNull) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.NULL_CHECK_ALWAYS_FAILS, |
| ); |
| } |
| super.visitPostfixExpression(node); |
| } |
| |
| @override |
| void visitPrefixExpression(PrefixExpression node) { |
| _deprecatedVerifier.prefixExpression(node); |
| super.visitPrefixExpression(node); |
| } |
| |
| @override |
| void visitRedirectingConstructorInvocation( |
| RedirectingConstructorInvocation node) { |
| _deprecatedVerifier.redirectingConstructorInvocation(node); |
| super.visitRedirectingConstructorInvocation(node); |
| } |
| |
| @override |
| void visitReturnStatement(ReturnStatement node) { |
| if (!_invalidAccessVerifier._inTestDirectory) { |
| _checkForReturnOfDoNotStore(node.expression); |
| } |
| super.visitReturnStatement(node); |
| } |
| |
| @override |
| void visitSetOrMapLiteral(SetOrMapLiteral node) { |
| _checkForDuplications(node); |
| super.visitSetOrMapLiteral(node); |
| } |
| |
| @override |
| void visitSimpleIdentifier(SimpleIdentifier node) { |
| _deprecatedVerifier.simpleIdentifier(node); |
| _invalidAccessVerifier.verify(node); |
| super.visitSimpleIdentifier(node); |
| } |
| |
| @override |
| void visitSuperConstructorInvocation(SuperConstructorInvocation node) { |
| _deprecatedVerifier.superConstructorInvocation(node); |
| _invalidAccessVerifier.verifySuperConstructorInvocation(node); |
| super.visitSuperConstructorInvocation(node); |
| } |
| |
| @override |
| void visitSuperFormalParameter(SuperFormalParameter node) { |
| _checkFinalParameter(node, node.keyword); |
| super.visitSuperFormalParameter(node); |
| } |
| |
| @override |
| void visitTopLevelVariableDeclaration(TopLevelVariableDeclaration node) { |
| _deprecatedVerifier.pushInDeprecatedMetadata(node.metadata); |
| |
| if (!_invalidAccessVerifier._inTestDirectory) { |
| for (var decl in node.variables.variables) { |
| _checkForAssignmentOfDoNotStore(decl.initializer); |
| } |
| } |
| |
| try { |
| super.visitTopLevelVariableDeclaration(node); |
| } finally { |
| _deprecatedVerifier.popInDeprecated(); |
| } |
| } |
| |
| /// Checks for the passed [IsExpression] for the unnecessary type check |
| /// warning codes as well as null checks expressed using an |
| /// [IsExpression]. |
| /// |
| /// Returns `true` if a warning code is generated on [node]. |
| /// See [WarningCode.TYPE_CHECK_IS_NOT_NULL], |
| /// [WarningCode.TYPE_CHECK_IS_NULL], |
| /// [WarningCode.UNNECESSARY_TYPE_CHECK_TRUE], and |
| /// [WarningCode.UNNECESSARY_TYPE_CHECK_FALSE]. |
| bool _checkAllTypeChecks(IsExpression node) { |
| var leftNode = node.expression; |
| var leftType = leftNode.typeOrThrow; |
| |
| var rightNode = node.type; |
| var rightType = rightNode.type as TypeImpl; |
| |
| void report() { |
| _errorReporter.atNode( |
| node, |
| node.notOperator == null |
| ? WarningCode.UNNECESSARY_TYPE_CHECK_TRUE |
| : WarningCode.UNNECESSARY_TYPE_CHECK_FALSE, |
| ); |
| } |
| |
| // `cannotResolve is X` or `cannotResolve is! X` |
| if (leftType is InvalidType) { |
| return false; |
| } |
| |
| // `is dynamic` or `is! dynamic` |
| if (rightType is DynamicType) { |
| report(); |
| return true; |
| } |
| |
| // `is CannotResolveType` or `is! CannotResolveType` |
| if (rightType is InvalidType) { |
| return false; |
| } |
| |
| // `is Null` or `is! Null` |
| if (rightType.isDartCoreNull) { |
| if (leftNode is NullLiteral) { |
| report(); |
| } else { |
| _errorReporter.atNode( |
| node, |
| node.notOperator == null |
| ? WarningCode.TYPE_CHECK_IS_NULL |
| : WarningCode.TYPE_CHECK_IS_NOT_NULL, |
| ); |
| } |
| return true; |
| } |
| |
| if (_typeSystem.isSubtypeOf(leftType, rightType)) { |
| report(); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| void _checkFinalParameter(FormalParameter node, Token? keyword) { |
| if (node.isFinal) { |
| _errorReporter.atToken( |
| keyword!, |
| WarningCode.UNNECESSARY_FINAL, |
| ); |
| } |
| } |
| |
| void _checkForAssignmentOfDoNotStore(Expression? expression) { |
| var expressionMap = _getSubExpressionsMarkedDoNotStore(expression); |
| for (var entry in expressionMap.entries) { |
| // All the elements returned by [_getSubExpressionsMarkedDoNotStore] are |
| // named elements, so we can safely assume `entry.value.name` is |
| // non-`null`. |
| _errorReporter.atNode( |
| entry.key, |
| WarningCode.ASSIGNMENT_OF_DO_NOT_STORE, |
| arguments: [entry.value.name!], |
| ); |
| } |
| } |
| |
| /// Checks the passed binary expression for [HintCode.DIVISION_OPTIMIZATION]. |
| /// |
| /// Returns whether a hint code is generated. |
| // TODO(srawlins): Remove this ASAP, as it is being replaced by the |
| // 'use_truncating_division' lint rule, to avoid double reporting. |
| bool _checkForDivisionOptimizationHint(BinaryExpression node) { |
| if (node.operator.type != TokenType.SLASH) return false; |
| |
| // Return if the two operands are not each `int`. |
| var leftType = node.leftOperand.staticType; |
| if (leftType == null || !leftType.isDartCoreInt) return false; |
| |
| var rightType = node.rightOperand.staticType; |
| if (rightType == null || !rightType.isDartCoreInt) return false; |
| |
| // Return if the '/' operator is not defined in core, or if we don't know |
| // its static type. |
| var methodElement = node.staticElement; |
| if (methodElement == null) return false; |
| |
| var libraryElement = methodElement.library; |
| if (!libraryElement.isDartCore) return false; |
| |
| var parent = node.parent; |
| if (parent is! ParenthesizedExpression) return false; |
| |
| var outermostParentheses = parent.thisOrAncestorMatching( |
| (e) => e.parent is! ParenthesizedExpression) as ParenthesizedExpression; |
| var grandParent = outermostParentheses.parent; |
| if (grandParent is! MethodInvocation) return false; |
| |
| // Report an error if the `(x / y)` expression has `toInt()` invoked on it. |
| if (grandParent.methodName.name == 'toInt' && |
| grandParent.argumentList.arguments.isEmpty) { |
| _errorReporter.atNode(grandParent, HintCode.DIVISION_OPTIMIZATION); |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /// Generate hints related to duplicate elements (keys) in sets (maps). |
| void _checkForDuplications(SetOrMapLiteral node) { |
| // This only checks for top-level elements. If, for, and spread elements |
| // that contribute duplicate values are not detected. |
| if (node.isConst) { |
| // This case is covered by the ErrorVerifier. |
| return; |
| } |
| var expressions = node.isSet |
| ? node.elements.whereType<Expression>() |
| : node.elements.whereType<MapLiteralEntry>().map((entry) => entry.key); |
| var alreadySeen = <DartObject>{}; |
| for (var expression in expressions) { |
| var constEvaluation = expression.computeConstantValue(); |
| if (constEvaluation.errors.isEmpty) { |
| var value = constEvaluation.value; |
| if (value != null && !alreadySeen.add(value)) { |
| var errorCode = node.isSet |
| ? WarningCode.EQUAL_ELEMENTS_IN_SET |
| : WarningCode.EQUAL_KEYS_IN_MAP; |
| _errorReporter.atNode( |
| expression, |
| errorCode, |
| ); |
| } |
| } |
| } |
| } |
| |
| /// Checks whether [node] violates the rules of [immutable]. |
| /// |
| /// If [node] is marked with [immutable] or inherits from a class or mixin |
| /// marked with [immutable], this function searches the fields of [node] and |
| /// its superclasses, reporting a warning if any non-final instance fields are |
| /// found. |
| void _checkForImmutable(NamedCompilationUnitMember node) { |
| /// Return `true` if the given class [element] or any superclass of it is |
| /// annotated with the `@immutable` annotation. |
| bool isOrInheritsImmutable( |
| InterfaceElement element, Set<InterfaceElement> visited) { |
| if (visited.add(element)) { |
| if (element.hasImmutable) { |
| return true; |
| } |
| for (InterfaceType interface in element.mixins) { |
| if (isOrInheritsImmutable(interface.element, visited)) { |
| return true; |
| } |
| } |
| for (InterfaceType mixin in element.interfaces) { |
| if (isOrInheritsImmutable(mixin.element, visited)) { |
| return true; |
| } |
| } |
| if (element.supertype != null) { |
| return isOrInheritsImmutable(element.supertype!.element, visited); |
| } |
| } |
| return false; |
| } |
| |
| Iterable<String> nonFinalInstanceFields(InterfaceElement element) { |
| return element.fields |
| .where((FieldElement field) => |
| !field.isSynthetic && !field.isFinal && !field.isStatic) |
| .map((FieldElement field) => '${element.name}.${field.name}'); |
| } |
| |
| Iterable<String> definedOrInheritedNonFinalInstanceFields( |
| InterfaceElement element, Set<InterfaceElement> visited) { |
| Iterable<String> nonFinalFields = []; |
| if (visited.add(element)) { |
| nonFinalFields = nonFinalInstanceFields(element); |
| nonFinalFields = nonFinalFields.followedBy(element.mixins.expand( |
| (InterfaceType mixin) => nonFinalInstanceFields(mixin.element))); |
| if (element.supertype != null) { |
| nonFinalFields = nonFinalFields.followedBy( |
| definedOrInheritedNonFinalInstanceFields( |
| element.supertype!.element, visited)); |
| } |
| } |
| return nonFinalFields; |
| } |
| |
| var element = node.declaredElement as InterfaceElement; |
| if (isOrInheritsImmutable(element, HashSet<InterfaceElement>())) { |
| Iterable<String> nonFinalFields = |
| definedOrInheritedNonFinalInstanceFields( |
| element, HashSet<InterfaceElement>()); |
| if (nonFinalFields.isNotEmpty) { |
| _errorReporter.atToken( |
| node.name, |
| WarningCode.MUST_BE_IMMUTABLE, |
| arguments: [nonFinalFields.join(', ')], |
| ); |
| } |
| } |
| } |
| |
| /// Check that the namespace exported by [node] does not include any elements |
| /// annotated with `@internal`. |
| void _checkForInternalExport(ExportDirective node) { |
| if (!_inPackagePublicApi) return; |
| |
| var libraryElement = node.element?.exportedLibrary; |
| if (libraryElement == null) return; |
| if (libraryElement.hasInternal) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.INVALID_EXPORT_OF_INTERNAL_ELEMENT, |
| arguments: [libraryElement.displayName], |
| ); |
| } |
| var exportNamespace = |
| NamespaceBuilder().createExportNamespaceForDirective(node.element!); |
| exportNamespace.definedNames.forEach((String name, Element element) { |
| if (element.hasInternal) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.INVALID_EXPORT_OF_INTERNAL_ELEMENT, |
| arguments: [element.displayName], |
| ); |
| } else if (element is FunctionElement) { |
| var signatureTypes = [ |
| ...element.parameters.map((p) => p.type), |
| element.returnType, |
| ...element.typeParameters.map((tp) => tp.bound), |
| ]; |
| for (var type in signatureTypes) { |
| var aliasElement = type?.alias?.element; |
| if (aliasElement != null && aliasElement.hasInternal) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.INVALID_EXPORT_OF_INTERNAL_ELEMENT_INDIRECTLY, |
| arguments: [aliasElement.name, element.displayName], |
| ); |
| } |
| } |
| } |
| }); |
| } |
| |
| void _checkForInvalidSealedSuperclass(NamedCompilationUnitMember node) { |
| bool currentPackageContains(Element element) { |
| return _isLibraryInWorkspacePackage(element.library); |
| } |
| |
| // [NamedCompilationUnitMember.declaredElement] is not necessarily a |
| // ClassElement, but [_checkForInvalidSealedSuperclass] should only be |
| // called with a [ClassOrMixinDeclaration], or a [ClassTypeAlias]. The |
| // `declaredElement` of these specific classes is a [ClassElement]. |
| var element = node.declaredElement as InterfaceElement; |
| // TODO(srawlins): Perhaps replace this with a getter on Element, like |
| // `Element.hasOrInheritsSealed`? |
| for (InterfaceType supertype in element.allSupertypes) { |
| var superclass = supertype.element; |
| if (superclass.hasSealed) { |
| if (!currentPackageContains(superclass)) { |
| if (element is MixinElement && |
| element.superclassConstraints.contains(supertype)) { |
| // This is a special violation of the sealed class contract, |
| // requiring specific messaging. |
| _errorReporter.atNode( |
| node, |
| WarningCode.MIXIN_ON_SEALED_CLASS, |
| arguments: [superclass.name.toString()], |
| ); |
| } else { |
| // This is a regular violation of the sealed class contract. |
| _errorReporter.atNode( |
| node, |
| WarningCode.SUBTYPE_OF_SEALED_CLASS, |
| arguments: [superclass.name.toString()], |
| ); |
| } |
| } |
| } |
| } |
| } |
| |
| void _checkForInvariantNanComparison(BinaryExpression node) { |
| void reportStartEnd( |
| ErrorCode errorCode, |
| SyntacticEntity startEntity, |
| SyntacticEntity endEntity, |
| ) { |
| var offset = startEntity.offset; |
| _errorReporter.atOffset( |
| offset: offset, |
| length: endEntity.end - offset, |
| errorCode: errorCode, |
| ); |
| } |
| |
| void checkLeftRight(ErrorCode errorCode) { |
| if (node.leftOperand.isDoubleNan) { |
| reportStartEnd(errorCode, node.leftOperand, node.operator); |
| } else if (node.rightOperand.isDoubleNan) { |
| reportStartEnd(errorCode, node.operator, node.rightOperand); |
| } |
| } |
| |
| if (node.operator.type == TokenType.BANG_EQ) { |
| checkLeftRight(WarningCode.UNNECESSARY_NAN_COMPARISON_TRUE); |
| } else if (node.operator.type == TokenType.EQ_EQ) { |
| checkLeftRight(WarningCode.UNNECESSARY_NAN_COMPARISON_FALSE); |
| } |
| } |
| |
| void _checkForInvariantNullComparison(BinaryExpression node) { |
| void reportStartEnd( |
| ErrorCode errorCode, |
| SyntacticEntity startEntity, |
| SyntacticEntity endEntity, |
| ) { |
| var offset = startEntity.offset; |
| _errorReporter.atOffset( |
| offset: offset, |
| length: endEntity.end - offset, |
| errorCode: errorCode, |
| ); |
| } |
| |
| void checkLeftRight(ErrorCode errorCode) { |
| if (node.leftOperand is NullLiteral) { |
| var rightType = node.rightOperand.typeOrThrow; |
| if (_typeSystem.isStrictlyNonNullable(rightType)) { |
| reportStartEnd(errorCode, node.leftOperand, node.operator); |
| } |
| } |
| |
| if (node.rightOperand is NullLiteral) { |
| var leftType = node.leftOperand.typeOrThrow; |
| if (_typeSystem.isStrictlyNonNullable(leftType)) { |
| reportStartEnd(errorCode, node.operator, node.rightOperand); |
| } |
| } |
| } |
| |
| if (node.operator.type == TokenType.BANG_EQ) { |
| checkLeftRight(WarningCode.UNNECESSARY_NULL_COMPARISON_TRUE); |
| } else if (node.operator.type == TokenType.EQ_EQ) { |
| checkLeftRight(WarningCode.UNNECESSARY_NULL_COMPARISON_FALSE); |
| } |
| } |
| |
| /// Check that the instance creation node is const if the constructor is |
| /// marked with [literal]. |
| void _checkForLiteralConstructorUse(InstanceCreationExpression node) { |
| ConstructorName constructorName = node.constructorName; |
| ConstructorElement? constructor = constructorName.staticElement; |
| if (constructor == null) { |
| return; |
| } |
| if (!node.isConst && constructor.hasLiteral && node.canBeConst) { |
| // Echoing jwren's `TODO` from _checkForDeprecatedMemberUse: |
| // TODO(jwren): We should modify ConstructorElement.getDisplayName(), or |
| // have the logic centralized elsewhere, instead of doing this logic |
| // here. |
| String fullConstructorName = constructorName.type.qualifiedName; |
| if (constructorName.name != null) { |
| fullConstructorName = '$fullConstructorName.${constructorName.name}'; |
| } |
| var warning = node.keyword?.keyword == Keyword.NEW |
| ? WarningCode.NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR_USING_NEW |
| : WarningCode.NON_CONST_CALL_TO_LITERAL_CONSTRUCTOR; |
| _errorReporter.atNode( |
| node, |
| warning, |
| arguments: [fullConstructorName], |
| ); |
| } |
| } |
| |
| /// Check that the imported library does not define a loadLibrary function. |
| /// The import has already been determined to be deferred when this is called. |
| /// |
| /// @param node the import directive to evaluate |
| /// @param importElement the [LibraryImportElement] retrieved from the node |
| /// @return `true` if and only if an error code is generated on the passed |
| /// node |
| /// See [CompileTimeErrorCode.IMPORT_DEFERRED_LIBRARY_WITH_LOAD_FUNCTION]. |
| bool _checkForLoadLibraryFunction( |
| ImportDirective node, LibraryImportElement importElement) { |
| var importedLibrary = importElement.importedLibrary; |
| var prefix = importElement.prefix?.element; |
| if (importedLibrary == null || prefix == null) { |
| return false; |
| } |
| var importNamespace = importElement.namespace; |
| var loadLibraryElement = importNamespace.getPrefixed( |
| prefix.name, FunctionElement.LOAD_LIBRARY_NAME); |
| if (loadLibraryElement != null) { |
| _errorReporter.atNode( |
| node, |
| HintCode.IMPORT_DEFERRED_LIBRARY_WITH_LOAD_FUNCTION, |
| ); |
| return true; |
| } |
| return false; |
| } |
| |
| void _checkForNullableEqualsParameterType(MethodDeclaration node) { |
| if (node.name.type != TokenType.EQ_EQ) { |
| return; |
| } |
| |
| var parameters = node.parameters; |
| if (parameters == null) { |
| return; |
| } |
| |
| if (parameters.parameters.length != 1) { |
| return; |
| } |
| |
| var parameter = parameters.parameters.first; |
| var parameterElement = parameter.declaredElement; |
| if (parameterElement == null) { |
| return; |
| } |
| |
| var type = parameterElement.type; |
| if (!type.isDartCoreObject && type is! DynamicType) { |
| // There is no legal way to define a nullable parameter type, which is not |
| // `dynamic` or `Object?`, so avoid double reporting here. |
| return; |
| } |
| |
| if (_typeSystem.isNullable(parameterElement.type)) { |
| _errorReporter.atToken( |
| node.name, |
| WarningCode.NON_NULLABLE_EQUALS_PARAMETER, |
| ); |
| } |
| } |
| |
| void _checkForNullableTypeInCatchClause(CatchClause node) { |
| var typeNode = node.exceptionType; |
| if (typeNode == null) { |
| return; |
| } |
| |
| var typeObj = typeNode.typeOrThrow; |
| if (typeObj is InvalidType) { |
| return; |
| } |
| |
| if (_typeSystem.isPotentiallyNullable(typeObj)) { |
| _errorReporter.atNode( |
| typeNode, |
| WarningCode.NULLABLE_TYPE_IN_CATCH_CLAUSE, |
| ); |
| } |
| } |
| |
| void _checkForReturnOfDoNotStore(Expression? expression) { |
| if (_inDoNotStoreMember) { |
| return; |
| } |
| var expressionMap = _getSubExpressionsMarkedDoNotStore(expression); |
| if (expressionMap.isNotEmpty) { |
| var parent = expression!.thisOrAncestorMatching( |
| (e) => e is FunctionDeclaration || e is MethodDeclaration) |
| as Declaration?; |
| if (parent == null) { |
| return; |
| } |
| for (var entry in expressionMap.entries) { |
| // All the elements returned by [_getSubExpressionsMarkedDoNotStore] are |
| // named elements, so we can safely assume `entry.value.name` is |
| // non-`null`. |
| _errorReporter.atNode( |
| entry.key, |
| WarningCode.RETURN_OF_DO_NOT_STORE, |
| arguments: [entry.value.name!, parent.declaredElement!.displayName], |
| ); |
| } |
| } |
| } |
| |
| /// Generates a warning for `noSuchMethod` methods that do nothing except of |
| /// calling another `noSuchMethod` which is not defined by `Object`. |
| /// |
| /// Returns `true` if a warning code is generated for [node]. |
| bool _checkForUnnecessaryNoSuchMethod(MethodDeclaration node) { |
| if (node.name.lexeme != FunctionElement.NO_SUCH_METHOD_METHOD_NAME) { |
| return false; |
| } |
| bool isNonObjectNoSuchMethodInvocation(Expression? invocation) { |
| if (invocation is MethodInvocation && |
| invocation.target is SuperExpression && |
| invocation.argumentList.arguments.length == 1) { |
| SimpleIdentifier name = invocation.methodName; |
| if (name.name == FunctionElement.NO_SUCH_METHOD_METHOD_NAME) { |
| var methodElement = name.staticElement; |
| var classElement = methodElement?.enclosingElement; |
| return methodElement is MethodElement && |
| classElement is ClassElement && |
| !classElement.isDartCoreObject; |
| } |
| } |
| return false; |
| } |
| |
| FunctionBody body = node.body; |
| if (body is ExpressionFunctionBody) { |
| if (isNonObjectNoSuchMethodInvocation(body.expression)) { |
| _errorReporter.atToken( |
| node.name, |
| WarningCode.UNNECESSARY_NO_SUCH_METHOD, |
| ); |
| return true; |
| } |
| } else if (body is BlockFunctionBody) { |
| List<Statement> statements = body.block.statements; |
| if (statements.length == 1) { |
| Statement returnStatement = statements.first; |
| if (returnStatement is ReturnStatement && |
| isNonObjectNoSuchMethodInvocation(returnStatement.expression)) { |
| _errorReporter.atToken( |
| node.name, |
| WarningCode.UNNECESSARY_NO_SUCH_METHOD, |
| ); |
| return true; |
| } |
| } |
| } |
| return false; |
| } |
| |
| /// Generate hints related to returning a set literal in an |
| /// [ExpressionFunctionBody], having a single expression, |
| /// for a function of `void` return type. |
| void _checkForUnnecessarySetLiteral( |
| FunctionBody body, FunctionExpression node) { |
| if (body is ExpressionFunctionBodyImpl) { |
| var parameterType = node.staticParameterElement?.type; |
| |
| DartType? returnType; |
| if (parameterType is FunctionType) { |
| returnType = parameterType.returnType; |
| } else { |
| var parent = node.parent; |
| if (parent is! FunctionDeclaration) return; |
| returnType = parent.returnType?.type; |
| } |
| if (returnType == null) return; |
| |
| bool isReturnVoid; |
| if (returnType is VoidType) { |
| isReturnVoid = true; |
| } else if (returnType is ParameterizedType && |
| (returnType.isDartAsyncFuture || returnType.isDartAsyncFutureOr)) { |
| var typeArguments = returnType.typeArguments; |
| isReturnVoid = |
| typeArguments.length == 1 && typeArguments.first is VoidType; |
| } else { |
| isReturnVoid = false; |
| } |
| if (isReturnVoid) { |
| var expression = body.expression; |
| if (expression is SetOrMapLiteralImpl && expression.isSet) { |
| _errorReporter.atNode( |
| expression, |
| WarningCode.UNNECESSARY_SET_LITERAL, |
| ); |
| } |
| } |
| } |
| } |
| |
| void _checkRequiredParameter(FormalParameterList node) { |
| var requiredParameters = |
| node.parameters.where((p) => p.declaredElement?.hasRequired == true); |
| var nonNamedParamsWithRequired = |
| requiredParameters.where((p) => p.isPositional); |
| var namedParamsWithRequiredAndDefault = requiredParameters |
| .where((p) => p.isNamed) |
| .where((p) => p.declaredElement!.defaultValueCode != null); |
| for (var param in nonNamedParamsWithRequired.where((p) => p.isOptional)) { |
| _errorReporter.atNode( |
| param, |
| WarningCode.INVALID_REQUIRED_OPTIONAL_POSITIONAL_PARAM, |
| arguments: [_formalParameterNameOrEmpty(param)], |
| ); |
| } |
| for (var param in nonNamedParamsWithRequired.where((p) => p.isRequired)) { |
| _errorReporter.atNode( |
| param, |
| WarningCode.INVALID_REQUIRED_POSITIONAL_PARAM, |
| arguments: [_formalParameterNameOrEmpty(param)], |
| ); |
| } |
| for (var param in namedParamsWithRequiredAndDefault) { |
| _errorReporter.atNode( |
| param, |
| WarningCode.INVALID_REQUIRED_NAMED_PARAM, |
| arguments: [_formalParameterNameOrEmpty(param)], |
| ); |
| } |
| } |
| |
| /// In "strict-inference" mode, check that each of the [parameters]' type is |
| /// specified. |
| /// |
| /// Only parameters which are referenced in [initializers] or [body] are |
| /// reported. If [initializers] and [body] are both null, the parameters are |
| /// assumed to originate from a typedef, function-typed parameter, or function |
| /// which is abstract or external. |
| void _checkStrictInferenceInParameters(FormalParameterList? parameters, |
| {List<ConstructorInitializer>? initializers, FunctionBody? body}) { |
| _UsedParameterVisitor? usedParameterVisitor; |
| |
| bool isParameterReferenced(SimpleFormalParameter parameter) { |
| if ((body == null || body is EmptyFunctionBody) && initializers == null) { |
| // The parameter is in a typedef, or function that is abstract, |
| // external, etc. |
| return true; |
| } |
| if (usedParameterVisitor == null) { |
| // Visit the function body and initializers once to determine whether |
| // each of the parameters is referenced. |
| usedParameterVisitor = _UsedParameterVisitor( |
| parameters!.parameters.map((p) => p.declaredElement!).toSet()); |
| body?.accept(usedParameterVisitor!); |
| for (var initializer in initializers ?? <ConstructorInitializer>[]) { |
| initializer.accept(usedParameterVisitor!); |
| } |
| } |
| |
| return usedParameterVisitor!.isUsed(parameter.declaredElement!); |
| } |
| |
| void checkParameterTypeIsKnown(SimpleFormalParameter parameter) { |
| if (parameter.type == null && isParameterReferenced(parameter)) { |
| ParameterElement element = parameter.declaredElement!; |
| _errorReporter.atNode( |
| parameter, |
| WarningCode.INFERENCE_FAILURE_ON_UNTYPED_PARAMETER, |
| arguments: [element.displayName], |
| ); |
| } |
| } |
| |
| if (_strictInference && parameters != null) { |
| for (FormalParameter parameter in parameters.parameters) { |
| if (parameter is SimpleFormalParameter) { |
| checkParameterTypeIsKnown(parameter); |
| } else if (parameter is DefaultFormalParameter) { |
| var nonDefault = parameter.parameter; |
| if (nonDefault is SimpleFormalParameter) { |
| checkParameterTypeIsKnown(nonDefault); |
| } |
| } |
| } |
| } |
| } |
| |
| /// In "strict-inference" mode, check that [returnType] is specified. |
| void _checkStrictInferenceReturnType( |
| AstNode? returnType, AstNode reportNode, String displayName) { |
| if (!_strictInference || returnType != null) { |
| return; |
| } |
| |
| switch (reportNode) { |
| case MethodDeclaration(): |
| _errorReporter.atToken( |
| reportNode.name, |
| WarningCode.INFERENCE_FAILURE_ON_FUNCTION_RETURN_TYPE, |
| arguments: [displayName], |
| ); |
| case FunctionDeclaration(): |
| _errorReporter.atToken( |
| reportNode.name, |
| WarningCode.INFERENCE_FAILURE_ON_FUNCTION_RETURN_TYPE, |
| arguments: [displayName], |
| ); |
| case _: |
| _errorReporter.atNode( |
| reportNode, |
| WarningCode.INFERENCE_FAILURE_ON_FUNCTION_RETURN_TYPE, |
| arguments: [displayName], |
| ); |
| } |
| } |
| |
| /// Return subexpressions that are marked `@doNotStore`, as a map so that |
| /// corresponding elements can be used in the diagnostic message. |
| Map<Expression, Element> _getSubExpressionsMarkedDoNotStore( |
| Expression? expression, |
| {Map<Expression, Element>? addTo}) { |
| var expressions = addTo ?? <Expression, Element>{}; |
| |
| Element? element; |
| if (expression is PropertyAccess) { |
| element = expression.propertyName.staticElement; |
| // Tear-off. |
| if (element is FunctionElement || element is MethodElement) { |
| element = null; |
| } |
| } else if (expression is MethodInvocation) { |
| element = expression.methodName.staticElement; |
| } else if (expression is Identifier) { |
| element = expression.staticElement; |
| // Tear-off. |
| if (element is FunctionElement || element is MethodElement) { |
| element = null; |
| } |
| } else if (expression is ConditionalExpression) { |
| _getSubExpressionsMarkedDoNotStore(expression.elseExpression, |
| addTo: expressions); |
| _getSubExpressionsMarkedDoNotStore(expression.thenExpression, |
| addTo: expressions); |
| } else if (expression is BinaryExpression) { |
| _getSubExpressionsMarkedDoNotStore(expression.leftOperand, |
| addTo: expressions); |
| _getSubExpressionsMarkedDoNotStore(expression.rightOperand, |
| addTo: expressions); |
| } else if (expression is FunctionExpression) { |
| var body = expression.body; |
| if (body is ExpressionFunctionBody) { |
| _getSubExpressionsMarkedDoNotStore(body.expression, addTo: expressions); |
| } |
| } |
| if (element is PropertyAccessorElement && element.isSynthetic) { |
| element = element.variable2; |
| } |
| |
| if (element != null && element.hasOrInheritsDoNotStore) { |
| expressions[expression!] = element; |
| } |
| |
| return expressions; |
| } |
| |
| bool _isLibraryInWorkspacePackage(LibraryElement? library) { |
| if (_workspacePackage == null || library == null) { |
| // Better to not make a big claim that they _are_ in the same package, |
| // if we were unable to determine what package [_currentLibrary] is in. |
| return false; |
| } |
| return _workspacePackage.contains(library.source); |
| } |
| |
| /// Checks for the passed as expression for the [WarningCode.UNNECESSARY_CAST] |
| /// hint code. |
| /// |
| /// Returns `true` if and only if an unnecessary cast hint should be generated |
| /// on [node]. See [WarningCode.UNNECESSARY_CAST]. |
| static bool isUnnecessaryCast(AsExpression node, TypeSystemImpl typeSystem) { |
| var leftType = node.expression.typeOrThrow; |
| var rightType = node.type.typeOrThrow; |
| |
| // `dynamicValue as SomeType` is a valid use case. |
| if (leftType is DynamicType) { |
| return false; |
| } |
| |
| // `cannotResolve is SomeType` is already reported. |
| if (leftType is InvalidType) { |
| return false; |
| } |
| |
| // `x as dynamic` is a valid use case. |
| if (rightType is DynamicType) { |
| return false; |
| } |
| |
| // `x as Unresolved` is already reported as an error. |
| if (rightType is InvalidType) { |
| return false; |
| } |
| |
| // The cast is necessary. |
| if (leftType != rightType) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| static String _formalParameterNameOrEmpty(FormalParameter node) { |
| return node.name?.lexeme ?? ''; |
| } |
| |
| static bool _hasNonVirtualAnnotation(ExecutableElement element) { |
| if (element is PropertyAccessorElement && element.isSynthetic) { |
| var variable = element.variable2; |
| if (variable != null && variable.hasNonVirtual) { |
| return true; |
| } |
| } |
| return element.hasNonVirtual; |
| } |
| } |
| |
| class _InvalidAccessVerifier { |
| static final _templateExtension = '.template'; |
| |
| final ErrorReporter _errorReporter; |
| final LibraryElement _library; |
| final WorkspacePackage? _workspacePackage; |
| |
| final bool _inTemplateSource; |
| final bool _inTestDirectory; |
| |
| InterfaceElement? _enclosingClass; |
| |
| _InvalidAccessVerifier(this._errorReporter, CompilationUnit unit, |
| this._library, this._workspacePackage) |
| : _inTemplateSource = |
| _library.source.fullName.contains(_templateExtension), |
| _inTestDirectory = unit.inTestDir; |
| |
| /// Produces a warning if [identifier] is accessed from an invalid location. |
| /// |
| /// In particular, a warning is produced in either of the two following cases: |
| /// |
| /// * The element associated with [identifier] is annotated with [internal], |
| /// and is accessed from outside the package in which the element is |
| /// declared. |
| /// * The element associated with [identifier] is annotated with [protected], |
| /// [visibleForTesting], and/or `visibleForTemplate`, and is accessed from a |
| /// location which is invalid as per the rules of each such annotation. |
| /// Conversely, if the element is annotated with more than one of these |
| /// annotations, the access is valid (and no warning is produced) if it |
| /// conforms to the rules of at least one of the annotations. |
| void verify(SimpleIdentifier identifier) { |
| if (identifier.inDeclarationContext() || _inCommentReference(identifier)) { |
| return; |
| } |
| |
| // This is the same logic used in [checkForDeprecatedMemberUseAtIdentifier] |
| // to avoid reporting an error twice for named constructors. |
| var parent = identifier.parent; |
| if (parent is ConstructorName && identical(identifier, parent.name)) { |
| return; |
| } |
| var grandparent = parent?.parent; |
| |
| var element = grandparent is ConstructorName |
| ? grandparent.staticElement |
| : identifier.writeOrReadElement; |
| |
| if (element == null) { |
| return; |
| } |
| _checkForInvalidDoNotSubmitAccess(identifier, element); |
| |
| if (_inCurrentLibrary(element)) { |
| return; |
| } |
| |
| if (parent is HideCombinator) { |
| return; |
| } |
| |
| _checkForInvalidInternalAccess( |
| parent: identifier.parent, |
| nameToken: identifier.token, |
| element: element, |
| ); |
| |
| _checkForOtherInvalidAccess(identifier, element); |
| } |
| |
| void verifyBinary(BinaryExpression node) { |
| var element = node.staticElement; |
| if (element != null && _hasVisibleForOverriding(element)) { |
| var operator = node.operator; |
| |
| if (node.leftOperand is SuperExpression) { |
| var methodDeclaration = node.thisOrAncestorOfType<MethodDeclaration>(); |
| if (methodDeclaration?.name.lexeme == operator.lexeme) { |
| return; |
| } |
| } |
| |
| _errorReporter.atToken( |
| operator, |
| WarningCode.INVALID_USE_OF_VISIBLE_FOR_OVERRIDING_MEMBER, |
| arguments: [operator.type.lexeme], |
| ); |
| } |
| } |
| |
| void verifyImport(ImportDirective node) { |
| var element = node.element?.importedLibrary; |
| if (element != null && |
| element.isInternal && |
| !_isLibraryInWorkspacePackage(element.library)) { |
| // The only way for an import directive's URI to have a `null` |
| // `stringValue` is if its string contains an interpolation, in which case |
| // the element would never have resolved in the first place. So we can |
| // safely assume `node.uri.stringValue` is non-`null`. |
| _errorReporter.atNode( |
| node, |
| WarningCode.INVALID_USE_OF_INTERNAL_MEMBER, |
| arguments: [node.uri.stringValue!], |
| ); |
| } |
| } |
| |
| void verifyNamedType(NamedType node) { |
| var element = node.element; |
| |
| var parent = node.parent; |
| if (parent is ConstructorName) { |
| element = parent.staticElement; |
| } |
| |
| if (element == null) { |
| return; |
| } |
| |
| _checkForInvalidDoNotSubmitAccess(node, element); |
| |
| if (_inCurrentLibrary(element)) { |
| return; |
| } |
| |
| _checkForInvalidInternalAccess( |
| parent: node, |
| nameToken: node.name2, |
| element: element, |
| ); |
| |
| _checkForOtherInvalidAccess(node, element); |
| } |
| |
| void verifyPatternField(PatternFieldImpl node) { |
| var element = node.element; |
| if (element == null) { |
| return; |
| } |
| _checkForInvalidDoNotSubmitAccess(node, element); |
| |
| if (_inCurrentLibrary(element)) { |
| return; |
| } |
| |
| if (element.isInternal && !_isLibraryInWorkspacePackage(element.library)) { |
| var fieldName = node.name; |
| if (fieldName == null) { |
| return; |
| } |
| var errorEntity = node.errorEntity; |
| |
| _errorReporter.atEntity( |
| errorEntity, |
| WarningCode.INVALID_USE_OF_INTERNAL_MEMBER, |
| arguments: [element.displayName], |
| ); |
| } |
| |
| _checkForOtherInvalidAccess(node, element); |
| } |
| |
| void verifySuperConstructorInvocation(SuperConstructorInvocation node) { |
| if (node.constructorName != null) { |
| // Named constructor calls are handled by [verify]. |
| return; |
| } |
| var element = node.staticElement; |
| if (element != null && |
| element.isInternal && |
| !_isLibraryInWorkspacePackage(element.library)) { |
| _errorReporter.atNode( |
| node, |
| WarningCode.INVALID_USE_OF_INTERNAL_MEMBER, |
| arguments: [element.name], |
| ); |
| } |
| } |
| |
| void _checkForInvalidDoNotSubmitAccess(AstNode node, Element element) { |
| if (element is ParameterElement || !_hasDoNotSubmit(element)) { |
| return; |
| } |
| |
| // It's valid for a member annotated with `@doNotSubmit` to access another |
| // member annotated with `@doNotSubmit`. For example, this is valid: |
| // ``` |
| // @doNotSubmit |
| // void foo() {} |
| // |
| // @doNotSubmit |
| // void bar() { |
| // // OK: `foo` is annotated with `@doNotSubmit` but so is `bar`. |
| // foo(); |
| // } |
| // ``` |
| var declaration = node.thisOrAncestorOfType<Declaration>(); |
| if (declaration != null) { |
| var element = declaration.declaredElement; |
| if (element != null && _hasDoNotSubmit(element)) { |
| return; |
| } |
| } |
| |
| var (name, errorEntity) = _getIdentifierNameAndErrorEntity(node, element); |
| _errorReporter.atOffset( |
| offset: errorEntity.offset, |
| length: errorEntity.length, |
| errorCode: WarningCode.invalid_use_of_do_not_submit_member, |
| arguments: [name], |
| ); |
| } |
| |
| // void a({@doNotSubmit int? b}) {} |
| // void c() { |
| // // Error: `b` is annotated with `@doNotSubmit` and it's a parameter. |
| // a(b: 0); |
| // } |
| void _checkForInvalidDoNotSubmitParameter(ArgumentList node) { |
| // void a({@doNotSubmit int? b}) { |
| // // OK: `b` is annotated with `@doNotSubmit` but it's a parameter. |
| // print(b); |
| // } |
| // |
| // void c({@doNotSubmit int? b}) { |
| // void d() { |
| // // OK: `b` is annotated with `@doNotSubmit` but it's a parent arg. |
| // print(b); |
| // } |
| // } |
| |
| // Check if the method being called is a parent method of the current node. |
| var bodyParent = node.thisOrAncestorOfType<FunctionBody>()?.parent; |
| if (bodyParent == node.thisOrAncestorOfType<FunctionDeclaration>() || |
| bodyParent == node.thisOrAncestorOfType<MethodDeclaration>()) { |
| return; |
| } |
| |
| for (var argument in node.arguments) { |
| var element = argument.staticParameterElement; |
| if (element != null) { |
| if (!_hasDoNotSubmit(element)) { |
| continue; |
| } |
| if (argument is NamedExpression) { |
| argument = argument.name.label; |
| var (name, errorEntity) = _getIdentifierNameAndErrorEntity( |
| argument, |
| element, |
| ); |
| _errorReporter.atOffset( |
| offset: errorEntity.offset, |
| length: errorEntity.length, |
| errorCode: WarningCode.invalid_use_of_do_not_submit_member, |
| arguments: [name], |
| ); |
| } else { |
| // For positional arguments. |
| _errorReporter.atNode( |
| argument, |
| WarningCode.invalid_use_of_do_not_submit_member, |
| arguments: [element.displayName], |
| ); |
| } |
| } |
| } |
| } |
| |
| void _checkForInvalidInternalAccess({ |
| required AstNode? parent, |
| required Token nameToken, |
| required Element element, |
| }) { |
| if (element.isInternal && !_isLibraryInWorkspacePackage(element.library)) { |
| String name; |
| SyntacticEntity node; |
| |
| var grandparent = parent?.parent; |
| |
| if (grandparent is ConstructorName) { |
| name = grandparent.toSource(); |
| node = grandparent; |
| } else { |
| name = nameToken.lexeme; |
| node = nameToken; |
| } |
| |
| _errorReporter.atEntity( |
| node, |
| WarningCode.INVALID_USE_OF_INTERNAL_MEMBER, |
| arguments: [name], |
| ); |
| } |
| } |
| |
| void _checkForOtherInvalidAccess(AstNode node, Element element) { |
| var hasProtected = element.isProtected; |
| if (hasProtected) { |
| var definingClass = element.enclosingElement as InterfaceElement; |
| if (_hasTypeOrSuperType(_enclosingClass, definingClass)) { |
| return; |
| } |
| } |
| |
| bool isVisibleForTemplateApplied = _isVisibleForTemplateApplied(element); |
| if (isVisibleForTemplateApplied) { |
| if (_inTemplateSource || _inExportDirective(node)) { |
| return; |
| } |
| } |
| |
| var hasVisibleForTesting = element.isVisibleForTesting; |
| if (hasVisibleForTesting) { |
| if (_inTestDirectory || _inExportDirective(node)) { |
| return; |
| } |
| } |
| |
| bool hasVisibleForOverriding = _hasVisibleForOverriding(element); |
| |
| // At this point, [identifier] was not cleared as protected access, nor |
| // cleared as access for templates or testing. Report a violation for each |
| // annotation present. |
| var (name, errorEntity) = _getIdentifierNameAndErrorEntity(node, element); |
| |
| var definingClass = element.enclosingElement; |
| if (definingClass == null) { |
| return; |
| } |
| if (hasProtected) { |
| _errorReporter.atEntity( |
| errorEntity, |
| WarningCode.INVALID_USE_OF_PROTECTED_MEMBER, |
| arguments: [name, definingClass.source!.uri], |
| ); |
| } |
| if (isVisibleForTemplateApplied) { |
| _errorReporter.atEntity( |
| errorEntity, |
| WarningCode.INVALID_USE_OF_VISIBLE_FOR_TEMPLATE_MEMBER, |
| arguments: [name, definingClass.source!.uri], |
| ); |
| } |
| |
| if (hasVisibleForTesting) { |
| _errorReporter.atEntity( |
| errorEntity, |
| WarningCode.INVALID_USE_OF_VISIBLE_FOR_TESTING_MEMBER, |
| arguments: [name, definingClass.source!.uri], |
| ); |
| } |
| |
| if (hasVisibleForOverriding) { |
| var parent = node.parent; |
| var validOverride = false; |
| if (parent is MethodInvocation && parent.target is SuperExpression || |
| parent is PropertyAccess && parent.target is SuperExpression) { |
| var grandparent = parent?.parent; |
| var methodDeclaration = |
| grandparent?.thisOrAncestorOfType<MethodDeclaration>(); |
| if (methodDeclaration?.name.lexeme == name) { |
| validOverride = true; |
| } |
| } |
| if (!validOverride) { |
| _errorReporter.atEntity( |
| errorEntity, |
| WarningCode.INVALID_USE_OF_VISIBLE_FOR_OVERRIDING_MEMBER, |
| arguments: [name], |
| ); |
| } |
| } |
| } |
| |
| bool _hasDoNotSubmit(Element element) { |
| if (element.hasDoNotSubmit) { |
| return true; |
| } |
| if (element is PropertyAccessorElement) { |
| var variable = element.variable2; |
| return variable != null && variable.hasDoNotSubmit; |
| } |
| return false; |
| } |
| |
| bool _hasTypeOrSuperType( |
| InterfaceElement? element, |
| InterfaceElement superElement, |
| ) { |
| if (element == null) { |
| return false; |
| } |
| return element.thisType.asInstanceOf(superElement) != null; |
| } |
| |
| bool _hasVisibleForOverriding(Element element) { |
| if (element.hasVisibleForOverriding) { |
| return true; |
| } |
| |
| if (element is PropertyAccessorElement) { |
| var variable = element.variable2; |
| return variable != null && variable.hasVisibleForOverriding; |
| } |
| |
| return false; |
| } |
| |
| bool _hasVisibleForTemplate(Element? element) { |
| if (element == null) { |
| return false; |
| } |
| if (element.hasVisibleForTemplate) { |
| return true; |
| } |
| if (element is PropertyAccessorElement) { |
| var variable = element.variable2; |
| if (variable != null && variable.hasVisibleForTemplate) { |
| return true; |
| } |
| } |
| var enclosingElement = element.enclosingElement; |
| if (_hasVisibleForTemplate(enclosingElement)) { |
| return true; |
| } |
| return false; |
| } |
| |
| bool _hasVisibleOutsideTemplate(Element element) { |
| if (element.hasVisibleOutsideTemplate) { |
| return true; |
| } |
| if (element is PropertyAccessorElement) { |
| var variable = element.variable2; |
| if (variable != null && variable.hasVisibleOutsideTemplate) { |
| return true; |
| } |
| } |
| var enclosingElement = element.enclosingElement; |
| if (enclosingElement != null && |
| _hasVisibleOutsideTemplate(enclosingElement)) { |
| return true; |
| } |
| return false; |
| } |
| |
| bool _inCommentReference(SimpleIdentifier identifier) { |
| var parent = identifier.parent; |
| return parent is CommentReference || parent?.parent is CommentReference; |
| } |
| |
| bool _inCurrentLibrary(Element element) => element.library == _library; |
| |
| bool _inExportDirective(AstNode node) => |
| node.parent is Combinator && node.parent!.parent is ExportDirective; |
| |
| bool _isLibraryInWorkspacePackage(LibraryElement? library) { |
| if (_workspacePackage == null || library == null) { |
| // Better to not make a big claim that they _are_ in the same package, |
| // if we were unable to determine what package [_currentLibrary] is in. |
| return false; |
| } |
| return _workspacePackage.contains(library.source); |
| } |
| |
| /// Check if @visibleForTemplate is applied to the given [Element]. |
| /// |
| /// [ClassElement], [EnumElement] and [MixinElement] are excluded from the |
| /// @visibleForTemplate access checks. Instead, the access restriction is |
| /// cascaded to all the corresponding members not annotated by |
| /// @visibleOutsideTemplate. |
| /// For other types of elements, check if they are annotated based on |
| /// `hasVisibleForTemplate` value. |
| bool _isVisibleForTemplateApplied(Element element) { |
| if (element is ClassElement || |
| element is EnumElement || |
| element is MixinElement) { |
| return false; |
| } else { |
| return _hasVisibleForTemplate(element) && |
| !_hasVisibleOutsideTemplate(element); |
| } |
| } |
| |
| static (String, SyntacticEntity) _getIdentifierNameAndErrorEntity( |
| AstNode node, |
| Element element, |
| ) { |
| String name; |
| SyntacticEntity errorEntity = node; |
| |
| var parent = node.parent; |
| var grandparent = parent?.parent; |
| if (node is Identifier) { |
| if (grandparent is ConstructorName) { |
| name = grandparent.toSource(); |
| errorEntity = grandparent; |
| } else { |
| name = node.name; |
| } |
| } else if (node is NamedType) { |
| if (parent is ConstructorName) { |
| name = parent.toSource(); |
| errorEntity = parent; |
| } else { |
| name = node.name2.lexeme; |
| } |
| } else if (node is PatternFieldImpl) { |
| name = element.displayName; |
| errorEntity = node.errorEntity; |
| } else { |
| throw StateError('Unhandled node type: ${node.runtimeType}'); |
| } |
| |
| return (name, errorEntity); |
| } |
| } |
| |
| /// A visitor that determines, upon visiting a function body and/or a |
| /// constructor's initializers, whether a parameter is referenced. |
| class _UsedParameterVisitor extends RecursiveAstVisitor<void> { |
| final Set<ParameterElement> _parameters; |
| |
| final Set<ParameterElement> _usedParameters = {}; |
| |
| _UsedParameterVisitor(this._parameters); |
| |
| bool isUsed(ParameterElement parameter) => |
| _usedParameters.contains(parameter); |
| |
| @override |
| void visitSimpleIdentifier(SimpleIdentifier node) { |
| var element = node.staticElement; |
| if (element is ExecutableMember) { |
| element = element.declaration; |
| } |
| if (_parameters.contains(element)) { |
| _usedParameters.add(element as ParameterElement); |
| } |
| } |
| } |
| |
| extension on Expression { |
| /// Whether this is the [PrefixedIdentifier] referring to `double.nan`. |
| // TODO(srawlins): This will return the wrong answer for `prefixed.double.nan` |
| // and for `import 'foo.dart' as double; double.nan`. |
| bool get isDoubleNan { |
| var self = this; |
| return self is PrefixedIdentifier && |
| self.prefix.name == 'double' && |
| self.identifier.name == 'nan'; |
| } |
| } |