| // Copyright (c) 2021, 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:analyzer/dart/ast/ast.dart'; |
| import 'package:analyzer/dart/element/type.dart'; |
| import 'package:analyzer/src/dart/ast/ast.dart'; |
| import 'package:analyzer/src/dart/element/member.dart'; |
| import 'package:analyzer/src/generated/resolver.dart'; |
| |
| /// A resolver for [InstanceCreationExpression] nodes. |
| /// |
| /// This resolver is responsible for rewriting a given |
| /// [InstanceCreationExpression] as a [MethodInvocation] if the parsed |
| /// [ConstructorName]'s `type` resolves to a [FunctionReference] or |
| /// [ConstructorReference], instead of a [NamedType]. |
| class InstanceCreationExpressionResolver { |
| /// The resolver driving this participant. |
| final ResolverVisitor _resolver; |
| |
| InstanceCreationExpressionResolver(this._resolver); |
| |
| void resolve(InstanceCreationExpressionImpl node) { |
| // The parser can parse certain code as [InstanceCreationExpression] when it |
| // might be an invocation of a method on a [FunctionReference] or |
| // [ConstructorReference]. In such a case, it is this resolver's |
| // responsibility to rewrite. For example, given: |
| // |
| // a.m<int>.apply(); |
| // |
| // the parser will give an InstanceCreationExpression (`a.m<int>.apply()`) |
| // with a name of `a.m<int>.apply` (ConstructorName) with a type of |
| // `a.m<int>` (TypeName with a name of `a.m` (PrefixedIdentifier) and |
| // typeArguments of `<int>`) and a name of `apply` (SimpleIdentifier). If |
| // `a.m<int>` is actually a function reference, then the |
| // InstanceCreationExpression needs to be rewritten as a MethodInvocation |
| // with a target of `a.m<int>` (a FunctionReference) and a name of `apply`. |
| if (node.keyword == null) { |
| var typeNameTypeArguments = node.constructorName.type2.typeArguments; |
| if (typeNameTypeArguments != null) { |
| // This could be a method call on a function reference or a constructor |
| // reference. |
| _resolveWithTypeNameWithTypeArguments(node, typeNameTypeArguments); |
| return; |
| } |
| } |
| |
| _resolveInstanceCreationExpression(node); |
| } |
| |
| void _inferArgumentTypes(covariant InstanceCreationExpressionImpl node) { |
| var constructorName = node.constructorName; |
| var typeName = constructorName.type2; |
| var typeArguments = typeName.typeArguments; |
| var elementToInfer = _resolver.inferenceHelper.constructorElementToInfer( |
| constructorName: constructorName, |
| definingLibrary: _resolver.definingLibrary, |
| ); |
| FunctionType? inferred; |
| |
| // If the constructor is generic, we'll have a ConstructorMember that |
| // substitutes in type arguments (possibly `dynamic`) from earlier in |
| // resolution. |
| // |
| // Otherwise we'll have a ConstructorElement, and we can skip inference |
| // because there's nothing to infer in a non-generic type. |
| if (elementToInfer != null) { |
| // TODO(leafp): Currently, we may re-infer types here, since we |
| // sometimes resolve multiple times. We should really check that we |
| // have not already inferred something. However, the obvious ways to |
| // check this don't work, since we may have been instantiated |
| // to bounds in an earlier phase, and we *do* want to do inference |
| // in that case. |
| |
| // Get back to the uninstantiated generic constructor. |
| // TODO(jmesserly): should we store this earlier in resolution? |
| // Or look it up, instead of jumping backwards through the Member? |
| var rawElement = elementToInfer.element; |
| var constructorType = elementToInfer.asType; |
| |
| inferred = _resolver.inferenceHelper.inferArgumentTypesForGeneric( |
| node, constructorType, typeArguments, |
| isConst: node.isConst, errorNode: node.constructorName); |
| |
| if (inferred != null) { |
| var arguments = node.argumentList; |
| InferenceContext.setType(arguments, inferred); |
| // Fix up the parameter elements based on inferred method. |
| arguments.correspondingStaticParameters = |
| ResolverVisitor.resolveArgumentsToParameters( |
| argumentList: arguments, |
| parameters: inferred.parameters, |
| ); |
| |
| constructorName.type2.type = inferred.returnType; |
| |
| // Update the static element as well. This is used in some cases, such |
| // as computing constant values. It is stored in two places. |
| var constructorElement = ConstructorMember.from( |
| rawElement, |
| inferred.returnType as InterfaceType, |
| ); |
| constructorName.staticElement = constructorElement; |
| } |
| } |
| |
| if (inferred == null) { |
| var constructorElement = constructorName.staticElement; |
| if (constructorElement != null) { |
| var type = constructorElement.type; |
| type = _resolver.toLegacyTypeIfOptOut(type) as FunctionType; |
| InferenceContext.setType(node.argumentList, type); |
| } |
| } |
| } |
| |
| void _resolveInstanceCreationExpression(InstanceCreationExpressionImpl node) { |
| var whyNotPromotedList = <WhyNotPromotedGetter>[]; |
| node.constructorName.accept(_resolver); |
| _inferArgumentTypes(node); |
| _resolver.visitArgumentList(node.argumentList, |
| whyNotPromotedList: whyNotPromotedList); |
| node.accept(_resolver.elementResolver); |
| _resolver.typeAnalyzer.visitInstanceCreationExpression(node); |
| _resolver.checkForArgumentTypesNotAssignableInList( |
| node.argumentList, whyNotPromotedList); |
| } |
| |
| /// Resolve [node] which has a [NamedType] with type arguments (given as |
| /// [typeNameTypeArguments]). |
| /// |
| /// The instance creation expression may actually be a method call on a |
| /// type-instantiated function reference or constructor reference. |
| void _resolveWithTypeNameWithTypeArguments( |
| InstanceCreationExpressionImpl node, |
| TypeArgumentListImpl typeNameTypeArguments, |
| ) { |
| var typeNameName = node.constructorName.type2.name; |
| if (typeNameName is SimpleIdentifierImpl) { |
| // TODO(srawlins): Lookup the name and potentially rewrite `node` as a |
| // [MethodInvocation]. |
| _resolveInstanceCreationExpression(node); |
| return; |
| } else if (typeNameName is PrefixedIdentifierImpl) { |
| // TODO(srawlins): Lookup the name and potentially rewrite `node` as a |
| // [MethodInvocation]. |
| _resolveInstanceCreationExpression(node); |
| } else { |
| assert( |
| false, 'Unexpected typeNameName type: ${typeNameName.runtimeType}'); |
| _resolveInstanceCreationExpression(node); |
| } |
| } |
| } |