001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.lang.types.expressions;
018    
019    import com.google.common.collect.Sets;
020    import com.intellij.psi.tree.IElementType;
021    import org.jetbrains.annotations.NotNull;
022    import org.jetbrains.annotations.Nullable;
023    import org.jetbrains.jet.lang.descriptors.DeclarationDescriptor;
024    import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
025    import org.jetbrains.jet.lang.descriptors.SimpleFunctionDescriptor;
026    import org.jetbrains.jet.lang.descriptors.VariableDescriptor;
027    import org.jetbrains.jet.lang.diagnostics.Errors;
028    import org.jetbrains.jet.lang.evaluate.EvaluatePackage;
029    import org.jetbrains.jet.lang.psi.*;
030    import org.jetbrains.jet.lang.resolve.*;
031    import org.jetbrains.jet.lang.resolve.calls.autocasts.DataFlowInfo;
032    import org.jetbrains.jet.lang.resolve.calls.context.TemporaryTraceAndCache;
033    import org.jetbrains.jet.lang.resolve.calls.model.ResolvedCall;
034    import org.jetbrains.jet.lang.resolve.calls.results.OverloadResolutionResults;
035    import org.jetbrains.jet.lang.resolve.calls.results.OverloadResolutionResultsUtil;
036    import org.jetbrains.jet.lang.resolve.name.Name;
037    import org.jetbrains.jet.lang.resolve.scopes.JetScope;
038    import org.jetbrains.jet.lang.resolve.scopes.WritableScope;
039    import org.jetbrains.jet.lang.resolve.scopes.receivers.ExpressionReceiver;
040    import org.jetbrains.jet.lang.types.JetType;
041    import org.jetbrains.jet.lang.types.JetTypeInfo;
042    import org.jetbrains.jet.lang.types.TypeUtils;
043    import org.jetbrains.jet.lang.types.lang.KotlinBuiltIns;
044    import org.jetbrains.jet.lexer.JetTokens;
045    
046    import java.util.Collection;
047    
048    import static org.jetbrains.jet.lang.diagnostics.Errors.*;
049    import static org.jetbrains.jet.lang.resolve.BindingContext.AMBIGUOUS_REFERENCE_TARGET;
050    import static org.jetbrains.jet.lang.resolve.BindingContext.VARIABLE_REASSIGNMENT;
051    import static org.jetbrains.jet.lang.resolve.calls.context.ContextDependency.INDEPENDENT;
052    import static org.jetbrains.jet.lang.types.TypeUtils.NO_EXPECTED_TYPE;
053    import static org.jetbrains.jet.lang.types.TypeUtils.noExpectedType;
054    
055    @SuppressWarnings("SuspiciousMethodCalls")
056    public class ExpressionTypingVisitorForStatements extends ExpressionTypingVisitor {
057        private final WritableScope scope;
058        private final BasicExpressionTypingVisitor basic;
059        private final ControlStructureTypingVisitor controlStructures;
060        private final PatternMatchingTypingVisitor patterns;
061    
062        public ExpressionTypingVisitorForStatements(
063                @NotNull ExpressionTypingInternals facade,
064                @NotNull WritableScope scope,
065                BasicExpressionTypingVisitor basic,
066                @NotNull ControlStructureTypingVisitor controlStructures,
067                @NotNull PatternMatchingTypingVisitor patterns) {
068            super(facade);
069            this.scope = scope;
070            this.basic = basic;
071            this.controlStructures = controlStructures;
072            this.patterns = patterns;
073        }
074    
075        @Nullable
076        private static JetType checkAssignmentType(
077                @Nullable JetType assignmentType,
078                @NotNull JetBinaryExpression expression,
079                @NotNull ExpressionTypingContext context
080        ) {
081            if (assignmentType != null && !KotlinBuiltIns.getInstance().isUnit(assignmentType) && !noExpectedType(context.expectedType) &&
082                TypeUtils.equalTypes(context.expectedType, assignmentType)) {
083                context.trace.report(Errors.ASSIGNMENT_TYPE_MISMATCH.on(expression, context.expectedType));
084                return null;
085            }
086            return DataFlowUtils.checkStatementType(expression, context);
087        }
088    
089        @Override
090        public JetTypeInfo visitObjectDeclaration(@NotNull JetObjectDeclaration declaration, ExpressionTypingContext context) {
091            TopDownAnalyzer.processClassOrObject(
092                    components.globalContext,
093                    scope, context.replaceScope(scope).replaceContextDependency(INDEPENDENT), scope.getContainingDeclaration(), declaration);
094            return DataFlowUtils.checkStatementType(declaration, context, context.dataFlowInfo);
095        }
096    
097        @Override
098        public JetTypeInfo visitProperty(@NotNull JetProperty property, ExpressionTypingContext typingContext) {
099            ExpressionTypingContext context = typingContext.replaceContextDependency(INDEPENDENT).replaceScope(scope);
100            JetTypeReference receiverTypeRef = property.getReceiverTypeRef();
101            if (receiverTypeRef != null) {
102                context.trace.report(LOCAL_EXTENSION_PROPERTY.on(receiverTypeRef));
103            }
104    
105            JetPropertyAccessor getter = property.getGetter();
106            if (getter != null) {
107                context.trace.report(LOCAL_VARIABLE_WITH_GETTER.on(getter));
108            }
109    
110            JetPropertyAccessor setter = property.getSetter();
111            if (setter != null) {
112                context.trace.report(LOCAL_VARIABLE_WITH_SETTER.on(setter));
113            }
114    
115            JetExpression delegateExpression = property.getDelegateExpression();
116            if (delegateExpression != null) {
117                components.expressionTypingServices.getTypeInfo(delegateExpression, context);
118                context.trace.report(LOCAL_VARIABLE_WITH_DELEGATE.on(property.getDelegate()));
119            }
120    
121            for (JetTypeParameter typeParameter : property.getTypeParameters()) {
122                AnnotationResolver.reportUnsupportedAnnotationForTypeParameter(typeParameter, context.trace);
123            }
124    
125            VariableDescriptor propertyDescriptor = components.expressionTypingServices.getDescriptorResolver().
126                    resolveLocalVariableDescriptor(scope, property, context.dataFlowInfo, context.trace);
127            JetExpression initializer = property.getInitializer();
128            DataFlowInfo dataFlowInfo = context.dataFlowInfo;
129            if (initializer != null) {
130                JetType outType = propertyDescriptor.getType();
131                JetTypeInfo typeInfo = facade.getTypeInfo(initializer, context.replaceExpectedType(outType));
132                dataFlowInfo = typeInfo.getDataFlowInfo();
133    
134                EvaluatePackage.recordCompileTimeValueForInitializerIfNeeded(propertyDescriptor, initializer, outType, context.trace);
135            }
136    
137            {
138                VariableDescriptor olderVariable = scope.getLocalVariable(propertyDescriptor.getName());
139                ExpressionTypingUtils.checkVariableShadowing(context, propertyDescriptor, olderVariable);
140            }
141    
142            scope.addVariableDescriptor(propertyDescriptor);
143            ModifiersChecker.create(context.trace).checkModifiersForLocalDeclaration(property);
144            return DataFlowUtils.checkStatementType(property, context, dataFlowInfo);
145        }
146    
147        @Override
148        public JetTypeInfo visitMultiDeclaration(@NotNull JetMultiDeclaration multiDeclaration, ExpressionTypingContext context) {
149            components.expressionTypingServices.getAnnotationResolver().resolveAnnotationsWithArguments(
150                    scope, multiDeclaration.getModifierList(), context.trace);
151    
152            JetExpression initializer = multiDeclaration.getInitializer();
153            if (initializer == null) {
154                context.trace.report(INITIALIZER_REQUIRED_FOR_MULTIDECLARATION.on(multiDeclaration));
155                return JetTypeInfo.create(null, context.dataFlowInfo);
156            }
157            ExpressionReceiver expressionReceiver = ExpressionTypingUtils.getExpressionReceiver(
158                    facade, initializer, context.replaceExpectedType(NO_EXPECTED_TYPE).replaceContextDependency(INDEPENDENT));
159            DataFlowInfo dataFlowInfo = facade.getTypeInfo(initializer, context).getDataFlowInfo();
160            if (expressionReceiver == null) {
161                return JetTypeInfo.create(null, dataFlowInfo);
162            }
163            components.expressionTypingUtils.defineLocalVariablesFromMultiDeclaration(scope, multiDeclaration, expressionReceiver, initializer, context);
164            return DataFlowUtils.checkStatementType(multiDeclaration, context, dataFlowInfo);
165        }
166    
167        @Override
168        public JetTypeInfo visitNamedFunction(@NotNull JetNamedFunction function, ExpressionTypingContext context) {
169            SimpleFunctionDescriptor functionDescriptor = components.expressionTypingServices.getDescriptorResolver().
170                    resolveFunctionDescriptorWithAnnotationArguments(
171                            scope.getContainingDeclaration(), scope, function, context.trace, context.dataFlowInfo);
172    
173            scope.addFunctionDescriptor(functionDescriptor);
174            JetScope functionInnerScope = FunctionDescriptorUtil.getFunctionInnerScope(context.scope, functionDescriptor, context.trace);
175            components.expressionTypingServices.checkFunctionReturnType(functionInnerScope, function, functionDescriptor, context.dataFlowInfo, null, context.trace);
176    
177            components.expressionTypingServices.resolveValueParameters(function.getValueParameters(), functionDescriptor.getValueParameters(),
178                                                                    scope, context.dataFlowInfo, context.trace, /* needCompleteAnalysis = */ true);
179    
180            ModifiersChecker.create(context.trace).checkModifiersForLocalDeclaration(function);
181            return DataFlowUtils.checkStatementType(function, context, context.dataFlowInfo);
182        }
183    
184        @Override
185        public JetTypeInfo visitClass(@NotNull JetClass klass, ExpressionTypingContext context) {
186            TopDownAnalyzer.processClassOrObject(
187                    components.globalContext,
188                    scope, context.replaceScope(scope).replaceContextDependency(INDEPENDENT), scope.getContainingDeclaration(), klass);
189            return DataFlowUtils.checkStatementType(klass, context, context.dataFlowInfo);
190        }
191    
192        @Override
193        public JetTypeInfo visitTypedef(@NotNull JetTypedef typedef, ExpressionTypingContext context) {
194            return super.visitTypedef(typedef, context); // TODO
195        }
196    
197        @Override
198        public JetTypeInfo visitDeclaration(@NotNull JetDeclaration dcl, ExpressionTypingContext context) {
199            return DataFlowUtils.checkStatementType(dcl, context, context.dataFlowInfo);
200        }
201    
202        @Override
203        public JetTypeInfo visitBinaryExpression(@NotNull JetBinaryExpression expression, ExpressionTypingContext context) {
204            JetSimpleNameExpression operationSign = expression.getOperationReference();
205            IElementType operationType = operationSign.getReferencedNameElementType();
206            JetTypeInfo result;
207            if (operationType == JetTokens.EQ) {
208                result = visitAssignment(expression, context);
209            }
210            else if (OperatorConventions.ASSIGNMENT_OPERATIONS.containsKey(operationType)) {
211                result = visitAssignmentOperation(expression, context);
212            }
213            else {
214                return facade.getTypeInfo(expression, context);
215            }
216            return DataFlowUtils.checkType(result.getType(), expression, context, result.getDataFlowInfo());
217        }
218    
219        @NotNull
220        protected JetTypeInfo visitAssignmentOperation(JetBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
221            //There is a temporary binding trace for an opportunity to resolve set method for array if needed (the initial trace should be used there)
222            TemporaryTraceAndCache temporary = TemporaryTraceAndCache.create(
223                    contextWithExpectedType, "trace to resolve array set method for binary expression", expression);
224            ExpressionTypingContext context = contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE)
225                    .replaceTraceAndCache(temporary).replaceContextDependency(INDEPENDENT);
226    
227            JetSimpleNameExpression operationSign = expression.getOperationReference();
228            IElementType operationType = operationSign.getReferencedNameElementType();
229            JetExpression leftOperand = expression.getLeft();
230            JetTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(leftOperand, context, facade);
231            JetType leftType = leftInfo.getType();
232            DataFlowInfo dataFlowInfo = leftInfo.getDataFlowInfo();
233    
234            JetExpression right = expression.getRight();
235            JetExpression left = leftOperand == null ? null : JetPsiUtil.deparenthesize(leftOperand);
236            if (right == null || left == null) {
237                temporary.commit();
238                return JetTypeInfo.create(null, dataFlowInfo);
239            }
240    
241            if (leftType == null) {
242                dataFlowInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(dataFlowInfo)).getDataFlowInfo();
243                context.trace.report(UNRESOLVED_REFERENCE.on(operationSign, operationSign));
244                temporary.commit();
245                return JetTypeInfo.create(null, dataFlowInfo);
246            }
247            ExpressionReceiver receiver = new ExpressionReceiver(left, leftType);
248    
249            // We check that defined only one of '+=' and '+' operations, and call it (in the case '+' we then also assign)
250            // Check for '+='
251            Name name = OperatorConventions.ASSIGNMENT_OPERATIONS.get(operationType);
252            TemporaryTraceAndCache temporaryForAssignmentOperation = TemporaryTraceAndCache.create(
253                    context, "trace to check assignment operation like '+=' for", expression);
254            OverloadResolutionResults<FunctionDescriptor> assignmentOperationDescriptors =
255                    components.callResolver.resolveBinaryCall(
256                            context.replaceTraceAndCache(temporaryForAssignmentOperation).replaceScope(scope),
257                            receiver, expression, name
258                    );
259            JetType assignmentOperationType = OverloadResolutionResultsUtil.getResultingType(assignmentOperationDescriptors,
260                                                                                             context.contextDependency);
261    
262            // Check for '+'
263            Name counterpartName = OperatorConventions.BINARY_OPERATION_NAMES.get(OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS.get(operationType));
264            TemporaryTraceAndCache temporaryForBinaryOperation = TemporaryTraceAndCache.create(
265                    context, "trace to check binary operation like '+' for", expression);
266            OverloadResolutionResults<FunctionDescriptor> binaryOperationDescriptors = components.callResolver.resolveBinaryCall(
267                    context.replaceTraceAndCache(temporaryForBinaryOperation).replaceScope(scope),
268                    receiver, expression, counterpartName
269            );
270            JetType binaryOperationType = OverloadResolutionResultsUtil.getResultingType(binaryOperationDescriptors, context.contextDependency);
271    
272            JetType type = assignmentOperationType != null ? assignmentOperationType : binaryOperationType;
273            if (assignmentOperationDescriptors.isSuccess() && binaryOperationDescriptors.isSuccess()) {
274                // Both 'plus()' and 'plusAssign()' available => ambiguity
275                OverloadResolutionResults<FunctionDescriptor> ambiguityResolutionResults = OverloadResolutionResultsUtil.ambiguity(assignmentOperationDescriptors, binaryOperationDescriptors);
276                context.trace.report(ASSIGN_OPERATOR_AMBIGUITY.on(operationSign, ambiguityResolutionResults.getResultingCalls()));
277                Collection<DeclarationDescriptor> descriptors = Sets.newHashSet();
278                for (ResolvedCall<? extends FunctionDescriptor> call : ambiguityResolutionResults.getResultingCalls()) {
279                    descriptors.add(call.getResultingDescriptor());
280                }
281                dataFlowInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(dataFlowInfo)).getDataFlowInfo();
282                context.trace.record(AMBIGUOUS_REFERENCE_TARGET, operationSign, descriptors);
283            }
284            else if (assignmentOperationType != null && (assignmentOperationDescriptors.isSuccess() || !binaryOperationDescriptors.isSuccess())) {
285                // There's 'plusAssign()', so we do a.plusAssign(b)
286                temporaryForAssignmentOperation.commit();
287                if (!KotlinBuiltIns.getInstance().isUnit(assignmentOperationType)) {
288                    context.trace.report(ASSIGNMENT_OPERATOR_SHOULD_RETURN_UNIT.on(operationSign, assignmentOperationDescriptors.getResultingDescriptor(), operationSign));
289                }
290            }
291            else {
292                // There's only 'plus()', so we try 'a = a + b'
293                temporaryForBinaryOperation.commit();
294                context.trace.record(VARIABLE_REASSIGNMENT, expression);
295                if (left instanceof JetArrayAccessExpression) {
296                    ExpressionTypingContext contextForResolve = context.replaceScope(scope).replaceBindingTrace(TemporaryBindingTrace.create(
297                            context.trace, "trace to resolve array set method for assignment", expression));
298                    basic.resolveArrayAccessSetMethod((JetArrayAccessExpression) left, right, contextForResolve, context.trace);
299                }
300                dataFlowInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(dataFlowInfo)).getDataFlowInfo();
301                BasicExpressionTypingVisitor.checkLValue(context.trace, leftOperand);
302            }
303            temporary.commit();
304            return JetTypeInfo.create(checkAssignmentType(type, expression, contextWithExpectedType), dataFlowInfo);
305        }
306    
307        @NotNull
308        protected JetTypeInfo visitAssignment(JetBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
309            ExpressionTypingContext context =
310                    contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE).replaceScope(scope).replaceContextDependency(INDEPENDENT);
311            JetExpression leftOperand = expression.getLeft();
312            JetExpression left = components.expressionTypingServices.deparenthesizeWithTypeResolution(leftOperand, context);
313            JetExpression right = expression.getRight();
314            if (left instanceof JetArrayAccessExpression) {
315                JetArrayAccessExpression arrayAccessExpression = (JetArrayAccessExpression) left;
316                if (right == null) return JetTypeInfo.create(null, context.dataFlowInfo);
317                JetTypeInfo typeInfo = basic.resolveArrayAccessSetMethod(arrayAccessExpression, right, context, context.trace);
318                BasicExpressionTypingVisitor.checkLValue(context.trace, arrayAccessExpression);
319                return JetTypeInfo.create(checkAssignmentType(typeInfo.getType(), expression, contextWithExpectedType),
320                                          typeInfo.getDataFlowInfo());
321            }
322            JetTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(left, context, facade);
323            JetType leftType = leftInfo.getType();
324            DataFlowInfo dataFlowInfo = leftInfo.getDataFlowInfo();
325            if (right != null) {
326                JetTypeInfo rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(dataFlowInfo).replaceExpectedType(leftType));
327                dataFlowInfo = rightInfo.getDataFlowInfo();
328            }
329            if (leftType != null && leftOperand != null) { //if leftType == null, some other error has been generated
330                BasicExpressionTypingVisitor.checkLValue(context.trace, leftOperand);
331            }
332            return DataFlowUtils.checkStatementType(expression, contextWithExpectedType, dataFlowInfo);
333        }
334    
335    
336        @Override
337        public JetTypeInfo visitExpression(@NotNull JetExpression expression, ExpressionTypingContext context) {
338            return facade.getTypeInfo(expression, context);
339        }
340    
341        @Override
342        public JetTypeInfo visitJetElement(@NotNull JetElement element, ExpressionTypingContext context) {
343            context.trace.report(UNSUPPORTED.on(element, "in a block"));
344            return JetTypeInfo.create(null, context.dataFlowInfo);
345        }
346    
347        @Override
348        public JetTypeInfo visitWhileExpression(@NotNull JetWhileExpression expression, ExpressionTypingContext context) {
349            return controlStructures.visitWhileExpression(expression, context, true);
350        }
351    
352        @Override
353        public JetTypeInfo visitDoWhileExpression(@NotNull JetDoWhileExpression expression, ExpressionTypingContext context) {
354            return controlStructures.visitDoWhileExpression(expression, context, true);
355        }
356    
357        @Override
358        public JetTypeInfo visitForExpression(@NotNull JetForExpression expression, ExpressionTypingContext context) {
359            return controlStructures.visitForExpression(expression, context, true);
360        }
361    
362        @Override
363        public JetTypeInfo visitAnnotatedExpression(
364                @NotNull JetAnnotatedExpression expression, ExpressionTypingContext data
365        ) {
366            return basic.visitAnnotatedExpression(expression, data, true);
367        }
368    
369        @Override
370        public JetTypeInfo visitIfExpression(@NotNull JetIfExpression expression, ExpressionTypingContext context) {
371            return controlStructures.visitIfExpression(expression, context, true);
372        }
373    
374        @Override
375        public JetTypeInfo visitWhenExpression(@NotNull JetWhenExpression expression, ExpressionTypingContext context) {
376            return patterns.visitWhenExpression(expression, context, true);
377        }
378    
379        @Override
380        public JetTypeInfo visitBlockExpression(@NotNull JetBlockExpression expression, ExpressionTypingContext context) {
381            return components.expressionTypingServices.getBlockReturnedType(expression, context, true);
382        }
383    
384        @Override
385        public JetTypeInfo visitParenthesizedExpression(@NotNull JetParenthesizedExpression expression, ExpressionTypingContext context) {
386            return basic.visitParenthesizedExpression(expression, context, true);
387        }
388    
389        @Override
390        public JetTypeInfo visitUnaryExpression(@NotNull JetUnaryExpression expression, ExpressionTypingContext context) {
391            return basic.visitUnaryExpression(expression, context, true);
392        }
393    }