| // Copyright (c) 2015, 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. |
| |
| // TODO(jmesserly): this was ported from package:dev_compiler, and needs to be |
| // refactored to fit into analyzer. |
| library analyzer.src.task.strong.checker; |
| |
| import 'package:analyzer/analyzer.dart'; |
| import 'package:analyzer/src/generated/ast.dart'; |
| import 'package:analyzer/src/generated/element.dart'; |
| import 'package:analyzer/src/generated/scanner.dart' show Token, TokenType; |
| |
| import 'info.dart'; |
| import 'rules.dart'; |
| |
| /// Checks for overriding declarations of fields and methods. This is used to |
| /// check overrides between classes and superclasses, interfaces, and mixin |
| /// applications. |
| class _OverrideChecker { |
| bool _failure = false; |
| final TypeRules _rules; |
| final AnalysisErrorListener _reporter; |
| |
| _OverrideChecker(this._rules, this._reporter); |
| |
| void check(ClassDeclaration node) { |
| if (node.element.type.isObject) return; |
| _checkSuperOverrides(node); |
| _checkMixinApplicationOverrides(node); |
| _checkAllInterfaceOverrides(node); |
| } |
| |
| /// Check overrides from mixin applications themselves. For example, in: |
| /// |
| /// A extends B with E, F |
| /// |
| /// we check: |
| /// |
| /// B & E against B (equivalently how E overrides B) |
| /// B & E & F against B & E (equivalently how F overrides both B and E) |
| void _checkMixinApplicationOverrides(ClassDeclaration node) { |
| var type = node.element.type; |
| var parent = type.superclass; |
| var mixins = type.mixins; |
| |
| // Check overrides from applying mixins |
| for (int i = 0; i < mixins.length; i++) { |
| var seen = new Set<String>(); |
| var current = mixins[i]; |
| var errorLocation = node.withClause.mixinTypes[i]; |
| for (int j = i - 1; j >= 0; j--) { |
| _checkIndividualOverridesFromType( |
| current, mixins[j], errorLocation, seen, true); |
| } |
| _checkIndividualOverridesFromType( |
| current, parent, errorLocation, seen, true); |
| } |
| } |
| |
| /// Check overrides between a class and its superclasses and mixins. For |
| /// example, in: |
| /// |
| /// A extends B with E, F |
| /// |
| /// we check A against B, B super classes, E, and F. |
| /// |
| /// Internally we avoid reporting errors twice and we visit classes bottom up |
| /// to ensure we report the most immediate invalid override first. For |
| /// example, in the following code we'll report that `Test` has an invalid |
| /// override with respect to `Parent` (as opposed to an invalid override with |
| /// respect to `Grandparent`): |
| /// |
| /// class Grandparent { |
| /// m(A a) {} |
| /// } |
| /// class Parent extends Grandparent { |
| /// m(A a) {} |
| /// } |
| /// class Test extends Parent { |
| /// m(B a) {} // invalid override |
| /// } |
| void _checkSuperOverrides(ClassDeclaration node) { |
| var seen = new Set<String>(); |
| var current = node.element.type; |
| var visited = new Set<InterfaceType>(); |
| do { |
| visited.add(current); |
| current.mixins.reversed.forEach( |
| (m) => _checkIndividualOverridesFromClass(node, m, seen, true)); |
| _checkIndividualOverridesFromClass(node, current.superclass, seen, true); |
| current = current.superclass; |
| } while (!current.isObject && !visited.contains(current)); |
| } |
| |
| /// Checks that implementations correctly override all reachable interfaces. |
| /// In particular, we need to check these overrides for the definitions in |
| /// the class itself and each its superclasses. If a superclass is not |
| /// abstract, then we can skip its transitive interfaces. For example, in: |
| /// |
| /// B extends C implements G |
| /// A extends B with E, F implements H, I |
| /// |
| /// we check: |
| /// |
| /// C against G, H, and I |
| /// B against G, H, and I |
| /// E against H and I // no check against G because B is a concrete class |
| /// F against H and I |
| /// A against H and I |
| void _checkAllInterfaceOverrides(ClassDeclaration node) { |
| var seen = new Set<String>(); |
| // Helper function to collect all reachable interfaces. |
| find(InterfaceType interfaceType, Set result) { |
| if (interfaceType == null || interfaceType.isObject) return; |
| if (result.contains(interfaceType)) return; |
| result.add(interfaceType); |
| find(interfaceType.superclass, result); |
| interfaceType.mixins.forEach((i) => find(i, result)); |
| interfaceType.interfaces.forEach((i) => find(i, result)); |
| } |
| |
| // Check all interfaces reachable from the `implements` clause in the |
| // current class against definitions here and in superclasses. |
| var localInterfaces = new Set<InterfaceType>(); |
| var type = node.element.type; |
| type.interfaces.forEach((i) => find(i, localInterfaces)); |
| _checkInterfacesOverrides(node, localInterfaces, seen, |
| includeParents: true); |
| |
| // Check also how we override locally the interfaces from parent classes if |
| // the parent class is abstract. Otherwise, these will be checked as |
| // overrides on the concrete superclass. |
| var superInterfaces = new Set<InterfaceType>(); |
| var parent = type.superclass; |
| // TODO(sigmund): we don't seem to be reporting the analyzer error that a |
| // non-abstract class is not implementing an interface. See |
| // https://github.com/dart-lang/dart-dev-compiler/issues/25 |
| while (parent != null && parent.element.isAbstract) { |
| parent.interfaces.forEach((i) => find(i, superInterfaces)); |
| parent = parent.superclass; |
| } |
| _checkInterfacesOverrides(node, superInterfaces, seen, |
| includeParents: false); |
| } |
| |
| /// Checks that [cls] and its super classes (including mixins) correctly |
| /// overrides each interface in [interfaces]. If [includeParents] is false, |
| /// then mixins are still checked, but the base type and it's transitive |
| /// supertypes are not. |
| /// |
| /// [cls] can be either a [ClassDeclaration] or a [InterfaceType]. For |
| /// [ClassDeclaration]s errors are reported on the member that contains the |
| /// invalid override, for [InterfaceType]s we use [errorLocation] instead. |
| void _checkInterfacesOverrides( |
| cls, Iterable<InterfaceType> interfaces, Set<String> seen, |
| {Set<InterfaceType> visited, |
| bool includeParents: true, |
| AstNode errorLocation}) { |
| var node = cls is ClassDeclaration ? cls : null; |
| var type = cls is InterfaceType ? cls : node.element.type; |
| |
| if (visited == null) { |
| visited = new Set<InterfaceType>(); |
| } else if (visited.contains(type)) { |
| // Malformed type. |
| return; |
| } else { |
| visited.add(type); |
| } |
| |
| // Check direct overrides on [type] |
| for (var interfaceType in interfaces) { |
| if (node != null) { |
| _checkIndividualOverridesFromClass(node, interfaceType, seen, false); |
| } else { |
| _checkIndividualOverridesFromType( |
| type, interfaceType, errorLocation, seen, false); |
| } |
| } |
| |
| // Check overrides from its mixins |
| for (int i = 0; i < type.mixins.length; i++) { |
| var loc = |
| errorLocation != null ? errorLocation : node.withClause.mixinTypes[i]; |
| for (var interfaceType in interfaces) { |
| // We copy [seen] so we can report separately if more than one mixin or |
| // the base class have an invalid override. |
| _checkIndividualOverridesFromType( |
| type.mixins[i], interfaceType, loc, new Set.from(seen), false); |
| } |
| } |
| |
| // Check overrides from its superclasses |
| if (includeParents) { |
| var parent = type.superclass; |
| if (parent.isObject) return; |
| var loc = errorLocation != null ? errorLocation : node.extendsClause; |
| // No need to copy [seen] here because we made copies above when reporting |
| // errors on mixins. |
| _checkInterfacesOverrides(parent, interfaces, seen, |
| visited: visited, includeParents: true, errorLocation: loc); |
| } |
| } |
| |
| /// Check that individual methods and fields in [subType] correctly override |
| /// the declarations in [baseType]. |
| /// |
| /// The [errorLocation] node indicates where errors are reported, see |
| /// [_checkSingleOverride] for more details. |
| /// |
| /// The set [seen] is used to avoid reporting overrides more than once. It |
| /// is used when invoking this function multiple times when checking several |
| /// types in a class hierarchy. Errors are reported only the first time an |
| /// invalid override involving a specific member is encountered. |
| _checkIndividualOverridesFromType( |
| InterfaceType subType, |
| InterfaceType baseType, |
| AstNode errorLocation, |
| Set<String> seen, |
| bool isSubclass) { |
| void checkHelper(ExecutableElement e) { |
| if (e.isStatic) return; |
| if (seen.contains(e.name)) return; |
| if (_checkSingleOverride(e, baseType, null, errorLocation, isSubclass)) { |
| seen.add(e.name); |
| } |
| } |
| subType.methods.forEach(checkHelper); |
| subType.accessors.forEach(checkHelper); |
| } |
| |
| /// Check that individual methods and fields in [subType] correctly override |
| /// the declarations in [baseType]. |
| /// |
| /// The [errorLocation] node indicates where errors are reported, see |
| /// [_checkSingleOverride] for more details. |
| _checkIndividualOverridesFromClass(ClassDeclaration node, |
| InterfaceType baseType, Set<String> seen, bool isSubclass) { |
| for (var member in node.members) { |
| if (member is ConstructorDeclaration) continue; |
| if (member is FieldDeclaration) { |
| if (member.isStatic) continue; |
| for (var variable in member.fields.variables) { |
| var element = variable.element as PropertyInducingElement; |
| var name = element.name; |
| if (seen.contains(name)) continue; |
| var getter = element.getter; |
| var setter = element.setter; |
| bool found = _checkSingleOverride( |
| getter, baseType, variable, member, isSubclass); |
| if (!variable.isFinal && |
| !variable.isConst && |
| _checkSingleOverride( |
| setter, baseType, variable, member, isSubclass)) { |
| found = true; |
| } |
| if (found) seen.add(name); |
| } |
| } else { |
| if ((member as MethodDeclaration).isStatic) continue; |
| var method = (member as MethodDeclaration).element; |
| if (seen.contains(method.name)) continue; |
| if (_checkSingleOverride( |
| method, baseType, member, member, isSubclass)) { |
| seen.add(method.name); |
| } |
| } |
| } |
| } |
| |
| /// Checks that [element] correctly overrides its corresponding member in |
| /// [type]. Returns `true` if an override was found, that is, if [element] has |
| /// a corresponding member in [type] that it overrides. |
| /// |
| /// The [errorLocation] is a node where the error is reported. For example, a |
| /// bad override of a method in a class with respect to its superclass is |
| /// reported directly at the method declaration. However, invalid overrides |
| /// from base classes to interfaces, mixins to the base they are applied to, |
| /// or mixins to interfaces are reported at the class declaration, since the |
| /// base class or members on their own were not incorrect, only combining them |
| /// with the interface was problematic. For example, these are example error |
| /// locations in these cases: |
| /// |
| /// error: base class introduces an invalid override. The type of B.foo is |
| /// not a subtype of E.foo: |
| /// class A extends B implements E { ... } |
| /// ^^^^^^^^^ |
| /// |
| /// error: mixin introduces an invalid override. The type of C.foo is not |
| /// a subtype of E.foo: |
| /// class A extends B with C implements E { ... } |
| /// ^ |
| /// |
| /// When checking for overrides from a type and it's super types, [node] is |
| /// the AST node that defines [element]. This is used to determine whether the |
| /// type of the element could be inferred from the types in the super classes. |
| bool _checkSingleOverride(ExecutableElement element, InterfaceType type, |
| AstNode node, AstNode errorLocation, bool isSubclass) { |
| assert(!element.isStatic); |
| |
| FunctionType subType = _rules.elementType(element); |
| // TODO(vsm): Test for generic |
| FunctionType baseType = _getMemberType(type, element); |
| if (baseType == null) return false; |
| |
| if (isSubclass && element is PropertyAccessorElement) { |
| // Disallow any overriding if the base class defines this member |
| // as a field. We effectively treat fields as final / non-virtual. |
| PropertyInducingElement field = _getMemberField(type, element); |
| if (field != null) { |
| _recordMessage(new InvalidFieldOverride( |
| errorLocation, element, type, subType, baseType)); |
| } |
| } |
| if (!_rules.isAssignable(subType, baseType)) { |
| // See whether non-assignable cases fit one of our common patterns: |
| // |
| // Common pattern 1: Inferable return type (on getters and methods) |
| // class A { |
| // int get foo => ...; |
| // String toString() { ... } |
| // } |
| // class B extends A { |
| // get foo => e; // no type specified. |
| // toString() { ... } // no return type specified. |
| // } |
| _recordMessage(new InvalidMethodOverride( |
| errorLocation, element, type, subType, baseType)); |
| } |
| return true; |
| } |
| |
| void _recordMessage(StaticInfo info) { |
| if (info == null) return; |
| var error = info.toAnalysisError(); |
| if (error.errorCode.errorSeverity == ErrorSeverity.ERROR) _failure = true; |
| _reporter.onError(error); |
| } |
| } |
| |
| /// Checks the body of functions and properties. |
| class CodeChecker extends RecursiveAstVisitor { |
| final TypeRules rules; |
| final AnalysisErrorListener reporter; |
| final _OverrideChecker _overrideChecker; |
| final bool _hints; |
| |
| bool _failure = false; |
| bool get failure => _failure || _overrideChecker._failure; |
| |
| void reset() { |
| _failure = false; |
| _overrideChecker._failure = false; |
| } |
| |
| CodeChecker(TypeRules rules, AnalysisErrorListener reporter, |
| {bool hints: false}) |
| : rules = rules, |
| reporter = reporter, |
| _hints = hints, |
| _overrideChecker = new _OverrideChecker(rules, reporter); |
| |
| @override |
| void visitComment(Comment node) { |
| // skip, no need to do typechecking inside comments (they may contain |
| // comment references which would require resolution). |
| } |
| |
| @override |
| void visitClassDeclaration(ClassDeclaration node) { |
| _overrideChecker.check(node); |
| super.visitClassDeclaration(node); |
| } |
| |
| @override |
| void visitAssignmentExpression(AssignmentExpression node) { |
| var token = node.operator; |
| if (token.type != TokenType.EQ) { |
| _checkCompoundAssignment(node); |
| } else { |
| DartType staticType = _getStaticType(node.leftHandSide); |
| checkAssignment(node.rightHandSide, staticType); |
| } |
| node.visitChildren(this); |
| } |
| |
| /// Check constructor declaration to ensure correct super call placement. |
| @override |
| void visitConstructorDeclaration(ConstructorDeclaration node) { |
| node.visitChildren(this); |
| |
| final init = node.initializers; |
| for (int i = 0, last = init.length - 1; i < last; i++) { |
| final node = init[i]; |
| if (node is SuperConstructorInvocation) { |
| _recordMessage(new InvalidSuperInvocation(node)); |
| } |
| } |
| } |
| |
| @override |
| void visitConstructorFieldInitializer(ConstructorFieldInitializer node) { |
| var field = node.fieldName; |
| var element = field.staticElement; |
| DartType staticType = rules.elementType(element); |
| checkAssignment(node.expression, staticType); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitForEachStatement(ForEachStatement node) { |
| // Check that the expression is an Iterable. |
| var expr = node.iterable; |
| var iterableType = node.awaitKeyword != null |
| ? rules.provider.streamType |
| : rules.provider.iterableType; |
| var loopVariable = node.identifier != null |
| ? node.identifier |
| : node.loopVariable?.identifier; |
| if (loopVariable != null) { |
| var iteratorType = loopVariable.staticType; |
| var checkedType = iterableType.substitute4([iteratorType]); |
| checkAssignment(expr, checkedType); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitForStatement(ForStatement node) { |
| if (node.condition != null) { |
| checkBoolean(node.condition); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitIfStatement(IfStatement node) { |
| checkBoolean(node.condition); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitDoStatement(DoStatement node) { |
| checkBoolean(node.condition); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitWhileStatement(WhileStatement node) { |
| checkBoolean(node.condition); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitSwitchStatement(SwitchStatement node) { |
| // SwitchStatement defines a boolean conversion to check the result of the |
| // case value == the switch value, but in dev_compiler we require a boolean |
| // return type from an overridden == operator (because Object.==), so |
| // checking in SwitchStatement shouldn't be necessary. |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitListLiteral(ListLiteral node) { |
| var type = rules.provider.dynamicType; |
| if (node.typeArguments != null) { |
| var targs = node.typeArguments.arguments; |
| if (targs.length > 0) type = targs[0].type; |
| } else if (node.staticType is InterfaceType) { |
| InterfaceType listT = node.staticType; |
| var targs = listT.typeArguments; |
| if (targs != null && targs.length > 0) type = targs[0]; |
| } |
| var elements = node.elements; |
| for (int i = 0; i < elements.length; i++) { |
| checkArgument(elements[i], type); |
| } |
| super.visitListLiteral(node); |
| } |
| |
| @override |
| void visitMapLiteral(MapLiteral node) { |
| var ktype = rules.provider.dynamicType; |
| var vtype = rules.provider.dynamicType; |
| if (node.typeArguments != null) { |
| var targs = node.typeArguments.arguments; |
| if (targs.length > 0) ktype = targs[0].type; |
| if (targs.length > 1) vtype = targs[1].type; |
| } else if (node.staticType is InterfaceType) { |
| InterfaceType mapT = node.staticType; |
| var targs = mapT.typeArguments; |
| if (targs != null) { |
| if (targs.length > 0) ktype = targs[0]; |
| if (targs.length > 1) vtype = targs[1]; |
| } |
| } |
| var entries = node.entries; |
| for (int i = 0; i < entries.length; i++) { |
| var entry = entries[i]; |
| checkArgument(entry.key, ktype); |
| checkArgument(entry.value, vtype); |
| } |
| super.visitMapLiteral(node); |
| } |
| |
| // Check invocations |
| void checkArgumentList(ArgumentList node, FunctionType type) { |
| NodeList<Expression> list = node.arguments; |
| int len = list.length; |
| for (int i = 0; i < len; ++i) { |
| Expression arg = list[i]; |
| ParameterElement element = arg.staticParameterElement; |
| if (element == null) { |
| if (type.parameters.length < len) { |
| // We found an argument mismatch, the analyzer will report this too, |
| // so no need to insert an error for this here. |
| continue; |
| } |
| element = type.parameters[i]; |
| // TODO(vsm): When can this happen? |
| assert(element != null); |
| } |
| DartType expectedType = rules.elementType(element); |
| if (expectedType == null) expectedType = rules.provider.dynamicType; |
| checkArgument(arg, expectedType); |
| } |
| } |
| |
| void checkArgument(Expression arg, DartType expectedType) { |
| // Preserve named argument structure, so their immediate parent is the |
| // method invocation. |
| if (arg is NamedExpression) { |
| arg = (arg as NamedExpression).expression; |
| } |
| checkAssignment(arg, expectedType); |
| } |
| |
| void checkFunctionApplication( |
| Expression node, Expression f, ArgumentList list) { |
| if (rules.isDynamicCall(f)) { |
| // If f is Function and this is a method invocation, we should have |
| // gotten an analyzer error, so no need to issue another error. |
| _recordDynamicInvoke(node, f); |
| } else { |
| checkArgumentList(list, rules.getTypeAsCaller(f)); |
| } |
| } |
| |
| @override |
| visitMethodInvocation(MethodInvocation node) { |
| var target = node.realTarget; |
| if (rules.isDynamicTarget(target) && |
| !_isObjectMethod(node, node.methodName)) { |
| _recordDynamicInvoke(node, target); |
| |
| // Mark the tear-off as being dynamic, too. This lets us distinguish |
| // cases like: |
| // |
| // dynamic d; |
| // d.someMethod(...); // the whole method call must be a dynamic send. |
| // |
| // ... from case like: |
| // |
| // SomeType s; |
| // s.someDynamicField(...); // static get, followed by dynamic call. |
| // |
| // The first case is handled here, the second case is handled below when |
| // we call [checkFunctionApplication]. |
| DynamicInvoke.set(node.methodName, true); |
| } else { |
| checkFunctionApplication(node, node.methodName, node.argumentList); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitFunctionExpressionInvocation(FunctionExpressionInvocation node) { |
| checkFunctionApplication(node, node.function, node.argumentList); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitRedirectingConstructorInvocation( |
| RedirectingConstructorInvocation node) { |
| var type = node.staticElement?.type; |
| // TODO(leafp): There's a TODO in visitRedirectingConstructorInvocation |
| // in the element_resolver to handle the case that the element is null |
| // and emit an error. In the meantime, just be defensive here. |
| if (type != null) { |
| checkArgumentList(node.argumentList, type); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitSuperConstructorInvocation(SuperConstructorInvocation node) { |
| var element = node.staticElement; |
| if (element != null) { |
| var type = node.staticElement.type; |
| checkArgumentList(node.argumentList, type); |
| } |
| node.visitChildren(this); |
| } |
| |
| void _checkReturnOrYield(Expression expression, AstNode node, |
| {bool yieldStar: false}) { |
| var body = node.getAncestor((n) => n is FunctionBody); |
| var type = rules.getExpectedReturnType(body, yieldStar: yieldStar); |
| if (type == null) { |
| // We have a type mismatch: the async/async*/sync* modifier does |
| // not match the return or yield type. We should have already gotten an |
| // analyzer error in this case. |
| return; |
| } |
| InterfaceType futureType = rules.provider.futureType; |
| DartType actualType = expression.staticType; |
| if (body.isAsynchronous && |
| !body.isGenerator && |
| actualType is InterfaceType && |
| actualType.element == futureType.element) { |
| type = futureType.substitute4([type]); |
| } |
| // TODO(vsm): Enforce void or dynamic (to void?) when expression is null. |
| if (expression != null) checkAssignment(expression, type); |
| } |
| |
| @override |
| void visitExpressionFunctionBody(ExpressionFunctionBody node) { |
| _checkReturnOrYield(node.expression, node); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitReturnStatement(ReturnStatement node) { |
| _checkReturnOrYield(node.expression, node); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitYieldStatement(YieldStatement node) { |
| _checkReturnOrYield(node.expression, node, yieldStar: node.star != null); |
| node.visitChildren(this); |
| } |
| |
| void _checkFieldAccess(AstNode node, AstNode target, SimpleIdentifier field) { |
| if ((rules.isDynamicTarget(target) || field.staticElement == null) && |
| !_isObjectProperty(target, field)) { |
| _recordDynamicInvoke(node, target); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitPropertyAccess(PropertyAccess node) { |
| _checkFieldAccess(node, node.realTarget, node.propertyName); |
| } |
| |
| @override |
| void visitPrefixedIdentifier(PrefixedIdentifier node) { |
| _checkFieldAccess(node, node.prefix, node.identifier); |
| } |
| |
| @override |
| void visitDefaultFormalParameter(DefaultFormalParameter node) { |
| // Check that defaults have the proper subtype. |
| var parameter = node.parameter; |
| var parameterType = rules.elementType(parameter.element); |
| assert(parameterType != null); |
| var defaultValue = node.defaultValue; |
| if (defaultValue != null) { |
| checkAssignment(defaultValue, parameterType); |
| } |
| |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitFieldFormalParameter(FieldFormalParameter node) { |
| var element = node.element; |
| var typeName = node.type; |
| if (typeName != null) { |
| var type = rules.elementType(element); |
| var fieldElement = |
| node.identifier.staticElement as FieldFormalParameterElement; |
| var fieldType = rules.elementType(fieldElement.field); |
| if (!rules.isSubTypeOf(type, fieldType)) { |
| var staticInfo = |
| new InvalidParameterDeclaration(rules, node, fieldType); |
| _recordMessage(staticInfo); |
| } |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitInstanceCreationExpression(InstanceCreationExpression node) { |
| var arguments = node.argumentList; |
| var element = node.staticElement; |
| if (element != null) { |
| var type = rules.elementType(node.staticElement); |
| checkArgumentList(arguments, type); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitVariableDeclarationList(VariableDeclarationList node) { |
| TypeName type = node.type; |
| if (type == null) { |
| // No checks are needed when the type is var. Although internally the |
| // typing rules may have inferred a more precise type for the variable |
| // based on the initializer. |
| } else { |
| var dartType = getType(type); |
| for (VariableDeclaration variable in node.variables) { |
| var initializer = variable.initializer; |
| if (initializer != null) { |
| checkAssignment(initializer, dartType); |
| } |
| } |
| } |
| node.visitChildren(this); |
| } |
| |
| void _checkRuntimeTypeCheck(AstNode node, TypeName typeName) { |
| var type = getType(typeName); |
| if (!rules.isGroundType(type)) { |
| _recordMessage(new NonGroundTypeCheckInfo(node, type)); |
| } |
| } |
| |
| @override |
| void visitAsExpression(AsExpression node) { |
| // We could do the same check as the IsExpression below, but that is |
| // potentially too conservative. Instead, at runtime, we must fail hard |
| // if the Dart as and the DDC as would return different values. |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitIsExpression(IsExpression node) { |
| _checkRuntimeTypeCheck(node, node.type); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitPrefixExpression(PrefixExpression node) { |
| if (node.operator.type == TokenType.BANG) { |
| checkBoolean(node.operand); |
| } else { |
| _checkUnary(node); |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitPostfixExpression(PostfixExpression node) { |
| _checkUnary(node); |
| node.visitChildren(this); |
| } |
| |
| void _checkUnary(/*PrefixExpression|PostfixExpression*/ node) { |
| var op = node.operator; |
| if (op.isUserDefinableOperator || |
| op.type == TokenType.PLUS_PLUS || |
| op.type == TokenType.MINUS_MINUS) { |
| if (rules.isDynamicTarget(node.operand)) { |
| _recordDynamicInvoke(node, node.operand); |
| } |
| // For ++ and --, even if it is not dynamic, we still need to check |
| // that the user defined method accepts an `int` as the RHS. |
| // We assume Analyzer has done this already. |
| } |
| } |
| |
| @override |
| void visitBinaryExpression(BinaryExpression node) { |
| var op = node.operator; |
| if (op.isUserDefinableOperator) { |
| if (rules.isDynamicTarget(node.leftOperand)) { |
| // Dynamic invocation |
| // TODO(vsm): Move this logic to the resolver? |
| if (op.type != TokenType.EQ_EQ && op.type != TokenType.BANG_EQ) { |
| _recordDynamicInvoke(node, node.leftOperand); |
| } |
| } else { |
| var element = node.staticElement; |
| // Method invocation. |
| if (element is MethodElement) { |
| var type = element.type; |
| // Analyzer should enforce number of parameter types, but check in |
| // case we have erroneous input. |
| if (type.normalParameterTypes.isNotEmpty) { |
| checkArgument(node.rightOperand, type.normalParameterTypes[0]); |
| } |
| } else { |
| // TODO(vsm): Assert that the analyzer found an error here? |
| } |
| } |
| } else { |
| // Non-method operator. |
| switch (op.type) { |
| case TokenType.AMPERSAND_AMPERSAND: |
| case TokenType.BAR_BAR: |
| checkBoolean(node.leftOperand); |
| checkBoolean(node.rightOperand); |
| break; |
| case TokenType.BANG_EQ: |
| break; |
| case TokenType.QUESTION_QUESTION: |
| break; |
| default: |
| assert(false); |
| } |
| } |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitConditionalExpression(ConditionalExpression node) { |
| checkBoolean(node.condition); |
| node.visitChildren(this); |
| } |
| |
| @override |
| void visitIndexExpression(IndexExpression node) { |
| var target = node.realTarget; |
| if (rules.isDynamicTarget(target)) { |
| _recordDynamicInvoke(node, target); |
| } else { |
| var element = node.staticElement; |
| if (element is MethodElement) { |
| var type = element.type; |
| // Analyzer should enforce number of parameter types, but check in |
| // case we have erroneous input. |
| if (type.normalParameterTypes.isNotEmpty) { |
| checkArgument(node.index, type.normalParameterTypes[0]); |
| } |
| } else { |
| // TODO(vsm): Assert that the analyzer found an error here? |
| } |
| } |
| node.visitChildren(this); |
| } |
| |
| DartType getType(TypeName name) { |
| return (name == null) ? rules.provider.dynamicType : name.type; |
| } |
| |
| /// Analyzer checks boolean conversions, but we need to check too, because |
| /// it uses the default assignability rules that allow `dynamic` and `Object` |
| /// to be assigned to bool with no message. |
| void checkBoolean(Expression expr) => |
| checkAssignment(expr, rules.provider.boolType); |
| |
| void checkAssignment(Expression expr, DartType type) { |
| if (expr is ParenthesizedExpression) { |
| checkAssignment(expr.expression, type); |
| } else { |
| _recordMessage(rules.checkAssignment(expr, type)); |
| } |
| } |
| |
| DartType _specializedBinaryReturnType( |
| TokenType op, DartType t1, DartType t2, DartType normalReturnType) { |
| // This special cases binary return types as per 16.26 and 16.27 of the |
| // Dart language spec. |
| switch (op) { |
| case TokenType.PLUS: |
| case TokenType.MINUS: |
| case TokenType.STAR: |
| case TokenType.TILDE_SLASH: |
| case TokenType.PERCENT: |
| case TokenType.PLUS_EQ: |
| case TokenType.MINUS_EQ: |
| case TokenType.STAR_EQ: |
| case TokenType.TILDE_SLASH_EQ: |
| case TokenType.PERCENT_EQ: |
| if (t1 == rules.provider.intType && |
| t2 == rules.provider.intType) return t1; |
| if (t1 == rules.provider.doubleType && |
| t2 == rules.provider.doubleType) return t1; |
| // This particular combo is not spelled out in the spec, but all |
| // implementations and analyzer seem to follow this. |
| if (t1 == rules.provider.doubleType && |
| t2 == rules.provider.intType) return t1; |
| } |
| return normalReturnType; |
| } |
| |
| void _checkCompoundAssignment(AssignmentExpression expr) { |
| var op = expr.operator.type; |
| assert(op.isAssignmentOperator && op != TokenType.EQ); |
| var methodElement = expr.staticElement; |
| if (methodElement == null) { |
| // Dynamic invocation |
| _recordDynamicInvoke(expr, expr.leftHandSide); |
| } else { |
| // Sanity check the operator |
| assert(methodElement.isOperator); |
| var functionType = methodElement.type; |
| var paramTypes = functionType.normalParameterTypes; |
| assert(paramTypes.length == 1); |
| assert(functionType.namedParameterTypes.isEmpty); |
| assert(functionType.optionalParameterTypes.isEmpty); |
| |
| // Check the lhs type |
| var staticInfo; |
| var rhsType = _getStaticType(expr.rightHandSide); |
| var lhsType = _getStaticType(expr.leftHandSide); |
| var returnType = _specializedBinaryReturnType( |
| op, lhsType, rhsType, functionType.returnType); |
| |
| if (!rules.isSubTypeOf(returnType, lhsType)) { |
| final numType = rules.provider.numType; |
| // Try to fix up the numerical case if possible. |
| if (rules.isSubTypeOf(lhsType, numType) && |
| rules.isSubTypeOf(lhsType, rhsType)) { |
| // This is also slightly different from spec, but allows us to keep |
| // compound operators in the int += num and num += dynamic cases. |
| staticInfo = DownCast.create( |
| rules, expr.rightHandSide, Coercion.cast(rhsType, lhsType)); |
| rhsType = lhsType; |
| } else { |
| // Static type error |
| staticInfo = new StaticTypeError(rules, expr, lhsType); |
| } |
| _recordMessage(staticInfo); |
| } |
| |
| // Check the rhs type |
| if (staticInfo is! CoercionInfo) { |
| var paramType = paramTypes.first; |
| staticInfo = rules.checkAssignment(expr.rightHandSide, paramType); |
| _recordMessage(staticInfo); |
| } |
| } |
| } |
| |
| bool _isObjectGetter(Expression target, SimpleIdentifier id) { |
| PropertyAccessorElement element = |
| rules.provider.objectType.element.getGetter(id.name); |
| return (element != null && !element.isStatic); |
| } |
| |
| bool _isObjectMethod(Expression target, SimpleIdentifier id) { |
| MethodElement element = |
| rules.provider.objectType.element.getMethod(id.name); |
| return (element != null && !element.isStatic); |
| } |
| |
| bool _isObjectProperty(Expression target, SimpleIdentifier id) { |
| return _isObjectGetter(target, id) || _isObjectMethod(target, id); |
| } |
| |
| DartType _getStaticType(Expression expr) { |
| return expr.staticType ?? rules.provider.dynamicType; |
| } |
| |
| void _recordDynamicInvoke(AstNode node, AstNode target) { |
| if (_hints) { |
| reporter.onError(new DynamicInvoke(rules, node).toAnalysisError()); |
| } |
| // TODO(jmesserly): we may eventually want to record if the whole operation |
| // (node) was dynamic, rather than the target, but this is an easier fit |
| // with what we used to do. |
| DynamicInvoke.set(target, true); |
| } |
| |
| void _recordMessage(StaticInfo info) { |
| if (info == null) return; |
| var error = info.toAnalysisError(); |
| var severity = error.errorCode.errorSeverity; |
| if (severity == ErrorSeverity.ERROR) _failure = true; |
| if (severity != ErrorSeverity.INFO || _hints) { |
| reporter.onError(error); |
| } |
| |
| if (info is CoercionInfo) { |
| // TODO(jmesserly): if we're run again on the same AST, we'll produce the |
| // same annotations. This should be harmless. This might go away once |
| // CodeChecker is integrated better with analyzer, as it will know that |
| // checking has already been performed. |
| // assert(CoercionInfo.get(info.node) == null); |
| CoercionInfo.set(info.node, info); |
| } |
| } |
| } |
| |
| // Return the field on type corresponding to member, or null if none |
| // exists or the "field" is actually a getter/setter. |
| PropertyInducingElement _getMemberField( |
| InterfaceType type, PropertyAccessorElement member) { |
| String memberName = member.name; |
| PropertyInducingElement field; |
| if (member.isGetter) { |
| // The subclass member is an explicit getter or a field |
| // - lookup the getter on the superclass. |
| var getter = type.getGetter(memberName); |
| if (getter == null || getter.isStatic) return null; |
| field = getter.variable; |
| } else if (!member.isSynthetic) { |
| // The subclass member is an explicit setter |
| // - lookup the setter on the superclass. |
| // Note: an implicit (synthetic) setter would have already been flagged on |
| // the getter above. |
| var setter = type.getSetter(memberName); |
| if (setter == null || setter.isStatic) return null; |
| field = setter.variable; |
| } else { |
| return null; |
| } |
| if (field.isSynthetic) return null; |
| return field; |
| } |
| |
| /// Looks up the declaration that matches [member] in [type] and returns it's |
| /// declared type. |
| FunctionType _getMemberType(InterfaceType type, ExecutableElement member) => |
| _memberTypeGetter(member)(type); |
| |
| typedef FunctionType _MemberTypeGetter(InterfaceType type); |
| |
| _MemberTypeGetter _memberTypeGetter(ExecutableElement member) { |
| String memberName = member.name; |
| final isGetter = member is PropertyAccessorElement && member.isGetter; |
| final isSetter = member is PropertyAccessorElement && member.isSetter; |
| |
| FunctionType f(InterfaceType type) { |
| ExecutableElement baseMethod; |
| |
| if (member.isPrivate) { |
| var subtypeLibrary = member.library; |
| var baseLibrary = type.element.library; |
| if (baseLibrary != subtypeLibrary) { |
| return null; |
| } |
| } |
| |
| try { |
| if (isGetter) { |
| assert(!isSetter); |
| // Look for getter or field. |
| baseMethod = type.getGetter(memberName); |
| } else if (isSetter) { |
| baseMethod = type.getSetter(memberName); |
| } else { |
| baseMethod = type.getMethod(memberName); |
| } |
| } catch (e) { |
| // TODO(sigmund): remove this try-catch block (see issue #48). |
| } |
| if (baseMethod == null || baseMethod.isStatic) return null; |
| return baseMethod.type; |
| } |
| ; |
| return f; |
| } |