001 /*
002 * Copyright 2010-2015 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.kotlin.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.kotlin.builtins.KotlinBuiltIns;
024 import org.jetbrains.kotlin.descriptors.DeclarationDescriptor;
025 import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
026 import org.jetbrains.kotlin.descriptors.VariableDescriptor;
027 import org.jetbrains.kotlin.diagnostics.Errors;
028 import org.jetbrains.kotlin.lexer.KtTokens;
029 import org.jetbrains.kotlin.name.Name;
030 import org.jetbrains.kotlin.psi.*;
031 import org.jetbrains.kotlin.resolve.DescriptorUtils;
032 import org.jetbrains.kotlin.resolve.TemporaryBindingTrace;
033 import org.jetbrains.kotlin.resolve.calls.context.TemporaryTraceAndCache;
034 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
035 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResults;
036 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResultsImpl;
037 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResultsUtil;
038 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowInfo;
039 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowValue;
040 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowValueFactory;
041 import org.jetbrains.kotlin.resolve.scopes.LexicalWritableScope;
042 import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver;
043 import org.jetbrains.kotlin.resolve.scopes.utils.ScopeUtilsKt;
044 import org.jetbrains.kotlin.types.KotlinType;
045 import org.jetbrains.kotlin.types.TypeUtils;
046 import org.jetbrains.kotlin.types.checker.KotlinTypeChecker;
047 import org.jetbrains.kotlin.types.expressions.typeInfoFactory.TypeInfoFactoryKt;
048
049 import java.util.Collection;
050
051 import static org.jetbrains.kotlin.diagnostics.Errors.*;
052 import static org.jetbrains.kotlin.psi.KtPsiUtil.deparenthesize;
053 import static org.jetbrains.kotlin.resolve.BindingContext.AMBIGUOUS_REFERENCE_TARGET;
054 import static org.jetbrains.kotlin.resolve.BindingContext.VARIABLE_REASSIGNMENT;
055 import static org.jetbrains.kotlin.resolve.calls.context.ContextDependency.INDEPENDENT;
056 import static org.jetbrains.kotlin.types.TypeUtils.NO_EXPECTED_TYPE;
057 import static org.jetbrains.kotlin.types.TypeUtils.noExpectedType;
058
059 @SuppressWarnings("SuspiciousMethodCalls")
060 public class ExpressionTypingVisitorForStatements extends ExpressionTypingVisitor {
061 private final LexicalWritableScope scope;
062 private final BasicExpressionTypingVisitor basic;
063 private final ControlStructureTypingVisitor controlStructures;
064 private final PatternMatchingTypingVisitor patterns;
065 private final FunctionsTypingVisitor functions;
066
067 public ExpressionTypingVisitorForStatements(
068 @NotNull ExpressionTypingInternals facade,
069 @NotNull LexicalWritableScope scope,
070 @NotNull BasicExpressionTypingVisitor basic,
071 @NotNull ControlStructureTypingVisitor controlStructures,
072 @NotNull PatternMatchingTypingVisitor patterns,
073 @NotNull FunctionsTypingVisitor functions
074 ) {
075 super(facade);
076 this.scope = scope;
077 this.basic = basic;
078 this.controlStructures = controlStructures;
079 this.patterns = patterns;
080 this.functions = functions;
081 }
082
083 @Nullable
084 private KotlinType checkAssignmentType(
085 @Nullable KotlinType assignmentType,
086 @NotNull KtBinaryExpression expression,
087 @NotNull ExpressionTypingContext context
088 ) {
089 if (assignmentType != null && !KotlinBuiltIns.isUnit(assignmentType) && !noExpectedType(context.expectedType) &&
090 !context.expectedType.isError() && TypeUtils.equalTypes(context.expectedType, assignmentType)) {
091 context.trace.report(Errors.ASSIGNMENT_TYPE_MISMATCH.on(expression, context.expectedType));
092 return null;
093 }
094 return components.dataFlowAnalyzer.checkStatementType(expression, context);
095 }
096
097 @Override
098 public JetTypeInfo visitObjectDeclaration(@NotNull KtObjectDeclaration declaration, ExpressionTypingContext context) {
099 components.localClassifierAnalyzer.processClassOrObject(
100 scope, context.replaceScope(scope).replaceContextDependency(INDEPENDENT),
101 scope.getOwnerDescriptor(),
102 declaration);
103 return TypeInfoFactoryKt.createTypeInfo(components.dataFlowAnalyzer.checkStatementType(declaration, context), context);
104 }
105
106 @Override
107 public JetTypeInfo visitProperty(@NotNull KtProperty property, ExpressionTypingContext typingContext) {
108 ExpressionTypingContext context = typingContext.replaceContextDependency(INDEPENDENT).replaceScope(scope);
109 KtTypeReference receiverTypeRef = property.getReceiverTypeReference();
110 if (receiverTypeRef != null) {
111 context.trace.report(LOCAL_EXTENSION_PROPERTY.on(receiverTypeRef));
112 }
113
114 KtPropertyAccessor getter = property.getGetter();
115 if (getter != null) {
116 context.trace.report(LOCAL_VARIABLE_WITH_GETTER.on(getter));
117 }
118
119 KtPropertyAccessor setter = property.getSetter();
120 if (setter != null) {
121 context.trace.report(LOCAL_VARIABLE_WITH_SETTER.on(setter));
122 }
123
124 KtExpression delegateExpression = property.getDelegateExpression();
125 if (delegateExpression != null) {
126 components.expressionTypingServices.getTypeInfo(delegateExpression, context);
127 context.trace.report(LOCAL_VARIABLE_WITH_DELEGATE.on(property.getDelegate()));
128 }
129
130 VariableDescriptor propertyDescriptor = components.descriptorResolver.
131 resolveLocalVariableDescriptor(scope, property, context.dataFlowInfo, context.trace);
132 KtExpression initializer = property.getInitializer();
133 JetTypeInfo typeInfo;
134 if (initializer != null) {
135 KotlinType outType = propertyDescriptor.getType();
136 typeInfo = facade.getTypeInfo(initializer, context.replaceExpectedType(outType));
137 DataFlowInfo dataFlowInfo = typeInfo.getDataFlowInfo();
138 KotlinType type = typeInfo.getType();
139 // At this moment we do not take initializer value into account if type is given for a property
140 // We can comment first part of this condition to take them into account, like here: var s: String? = "xyz"
141 // In this case s will be not-nullable until it is changed
142 if (property.getTypeReference() == null && type != null) {
143 DataFlowValue variableDataFlowValue = DataFlowValueFactory.createDataFlowValueForProperty(
144 property, propertyDescriptor, context.trace.getBindingContext(),
145 DescriptorUtils.getContainingModuleOrNull(scope.getOwnerDescriptor()));
146 DataFlowValue initializerDataFlowValue = DataFlowValueFactory.createDataFlowValue(initializer, type, context);
147 // We cannot say here anything new about initializerDataFlowValue
148 // except it has the same value as variableDataFlowValue
149 typeInfo = typeInfo.replaceDataFlowInfo(dataFlowInfo.assign(variableDataFlowValue, initializerDataFlowValue));
150 }
151 }
152 else {
153 typeInfo = TypeInfoFactoryKt.noTypeInfo(context);
154 }
155
156 {
157 VariableDescriptor olderVariable = ScopeUtilsKt.getLocalVariable(scope, propertyDescriptor.getName());
158 ExpressionTypingUtils.checkVariableShadowing(context, propertyDescriptor, olderVariable);
159 }
160
161 scope.addVariableDescriptor(propertyDescriptor);
162 components.modifiersChecker.withTrace(context.trace).checkModifiersForLocalDeclaration(property, propertyDescriptor);
163 components.identifierChecker.checkDeclaration(property, context.trace);
164 return typeInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(property, context));
165 }
166
167 @Override
168 public JetTypeInfo visitMultiDeclaration(@NotNull KtMultiDeclaration multiDeclaration, ExpressionTypingContext context) {
169 components.annotationResolver.resolveAnnotationsWithArguments(scope, multiDeclaration.getModifierList(), context.trace);
170
171 KtExpression initializer = multiDeclaration.getInitializer();
172 if (initializer == null) {
173 context.trace.report(INITIALIZER_REQUIRED_FOR_MULTIDECLARATION.on(multiDeclaration));
174 return TypeInfoFactoryKt.noTypeInfo(context);
175 }
176 ExpressionReceiver expressionReceiver = ExpressionTypingUtils.getExpressionReceiver(
177 facade, initializer, context.replaceExpectedType(NO_EXPECTED_TYPE).replaceContextDependency(INDEPENDENT));
178 JetTypeInfo typeInfo = facade.getTypeInfo(initializer, context);
179 if (expressionReceiver == null) {
180 return TypeInfoFactoryKt.noTypeInfo(context);
181 }
182 components.multiDeclarationResolver.defineLocalVariablesFromMultiDeclaration(scope, multiDeclaration, expressionReceiver, initializer, context);
183 components.modifiersChecker.withTrace(context.trace).checkModifiersForMultiDeclaration(multiDeclaration);
184 components.identifierChecker.checkDeclaration(multiDeclaration, context.trace);
185 return typeInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(multiDeclaration, context));
186 }
187
188 @Override
189 public JetTypeInfo visitNamedFunction(@NotNull KtNamedFunction function, ExpressionTypingContext context) {
190 return functions.visitNamedFunction(function, context, true, scope);
191 }
192
193 @Override
194 public JetTypeInfo visitClass(@NotNull KtClass klass, ExpressionTypingContext context) {
195 components.localClassifierAnalyzer.processClassOrObject(
196 scope, context.replaceScope(scope).replaceContextDependency(INDEPENDENT),
197 scope.getOwnerDescriptor(),
198 klass);
199 return TypeInfoFactoryKt.createTypeInfo(components.dataFlowAnalyzer.checkStatementType(klass, context), context);
200 }
201
202 @Override
203 public JetTypeInfo visitTypedef(@NotNull KtTypedef typedef, ExpressionTypingContext context) {
204 context.trace.report(UNSUPPORTED.on(typedef, "Typedefs are not supported"));
205 return super.visitTypedef(typedef, context);
206 }
207
208 @Override
209 public JetTypeInfo visitDeclaration(@NotNull KtDeclaration dcl, ExpressionTypingContext context) {
210 return TypeInfoFactoryKt.createTypeInfo(components.dataFlowAnalyzer.checkStatementType(dcl, context), context);
211 }
212
213 @Override
214 public JetTypeInfo visitBinaryExpression(@NotNull KtBinaryExpression expression, ExpressionTypingContext context) {
215 KtSimpleNameExpression operationSign = expression.getOperationReference();
216 IElementType operationType = operationSign.getReferencedNameElementType();
217 JetTypeInfo result;
218 if (operationType == KtTokens.EQ) {
219 result = visitAssignment(expression, context);
220 }
221 else if (OperatorConventions.ASSIGNMENT_OPERATIONS.containsKey(operationType)) {
222 result = visitAssignmentOperation(expression, context);
223 }
224 else {
225 return facade.getTypeInfo(expression, context);
226 }
227 return components.dataFlowAnalyzer.checkType(result, expression, context);
228 }
229
230 @NotNull
231 protected JetTypeInfo visitAssignmentOperation(KtBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
232 //There is a temporary binding trace for an opportunity to resolve set method for array if needed (the initial trace should be used there)
233 TemporaryTraceAndCache temporary = TemporaryTraceAndCache.create(
234 contextWithExpectedType, "trace to resolve array set method for binary expression", expression);
235 ExpressionTypingContext context = contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE)
236 .replaceTraceAndCache(temporary).replaceContextDependency(INDEPENDENT);
237
238 KtSimpleNameExpression operationSign = expression.getOperationReference();
239 IElementType operationType = operationSign.getReferencedNameElementType();
240 KtExpression leftOperand = expression.getLeft();
241 JetTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(leftOperand, context, facade);
242 KotlinType leftType = leftInfo.getType();
243
244 KtExpression right = expression.getRight();
245 KtExpression left = leftOperand == null ? null : deparenthesize(leftOperand);
246 if (right == null || left == null) {
247 temporary.commit();
248 return leftInfo.clearType();
249 }
250
251 if (leftType == null) {
252 JetTypeInfo rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
253 context.trace.report(UNRESOLVED_REFERENCE.on(operationSign, operationSign));
254 temporary.commit();
255 return rightInfo.clearType();
256 }
257 ExpressionReceiver receiver = new ExpressionReceiver(left, leftType);
258
259 // We check that defined only one of '+=' and '+' operations, and call it (in the case '+' we then also assign)
260 // Check for '+='
261 Name name = OperatorConventions.ASSIGNMENT_OPERATIONS.get(operationType);
262 TemporaryTraceAndCache temporaryForAssignmentOperation = TemporaryTraceAndCache.create(
263 context, "trace to check assignment operation like '+=' for", expression);
264 OverloadResolutionResults<FunctionDescriptor> assignmentOperationDescriptors =
265 components.callResolver.resolveBinaryCall(
266 context.replaceTraceAndCache(temporaryForAssignmentOperation).replaceScope(scope),
267 receiver, expression, name
268 );
269 KotlinType assignmentOperationType = OverloadResolutionResultsUtil.getResultingType(assignmentOperationDescriptors,
270 context.contextDependency);
271
272 OverloadResolutionResults<FunctionDescriptor> binaryOperationDescriptors;
273 KotlinType binaryOperationType;
274 TemporaryTraceAndCache temporaryForBinaryOperation = TemporaryTraceAndCache.create(
275 context, "trace to check binary operation like '+' for", expression);
276 TemporaryBindingTrace ignoreReportsTrace = TemporaryBindingTrace.create(context.trace, "Trace for checking assignability");
277 boolean lhsAssignable = basic.checkLValue(ignoreReportsTrace, context, left, right);
278 if (assignmentOperationType == null || lhsAssignable) {
279 // Check for '+'
280 Name counterpartName = OperatorConventions.BINARY_OPERATION_NAMES.get(OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS.get(operationType));
281 binaryOperationDescriptors = components.callResolver.resolveBinaryCall(
282 context.replaceTraceAndCache(temporaryForBinaryOperation).replaceScope(scope),
283 receiver, expression, counterpartName
284 );
285 binaryOperationType = OverloadResolutionResultsUtil.getResultingType(binaryOperationDescriptors, context.contextDependency);
286 }
287 else {
288 binaryOperationDescriptors = OverloadResolutionResultsImpl.nameNotFound();
289 binaryOperationType = null;
290 }
291
292 KotlinType type = assignmentOperationType != null ? assignmentOperationType : binaryOperationType;
293 JetTypeInfo rightInfo = leftInfo;
294 if (assignmentOperationDescriptors.isSuccess() && binaryOperationDescriptors.isSuccess()) {
295 // Both 'plus()' and 'plusAssign()' available => ambiguity
296 OverloadResolutionResults<FunctionDescriptor> ambiguityResolutionResults = OverloadResolutionResultsUtil.ambiguity(assignmentOperationDescriptors, binaryOperationDescriptors);
297 context.trace.report(ASSIGN_OPERATOR_AMBIGUITY.on(operationSign, ambiguityResolutionResults.getResultingCalls()));
298 Collection<DeclarationDescriptor> descriptors = Sets.newHashSet();
299 for (ResolvedCall<?> resolvedCall : ambiguityResolutionResults.getResultingCalls()) {
300 descriptors.add(resolvedCall.getResultingDescriptor());
301 }
302 rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
303 context.trace.record(AMBIGUOUS_REFERENCE_TARGET, operationSign, descriptors);
304 }
305 else if (assignmentOperationType != null && (assignmentOperationDescriptors.isSuccess() || !binaryOperationDescriptors.isSuccess())) {
306 // There's 'plusAssign()', so we do a.plusAssign(b)
307 temporaryForAssignmentOperation.commit();
308 if (!KotlinTypeChecker.DEFAULT.equalTypes(components.builtIns.getUnitType(), assignmentOperationType)) {
309 context.trace.report(ASSIGNMENT_OPERATOR_SHOULD_RETURN_UNIT.on(operationSign, assignmentOperationDescriptors.getResultingDescriptor(), operationSign));
310 }
311 }
312 else {
313 // There's only 'plus()', so we try 'a = a + b'
314 temporaryForBinaryOperation.commit();
315 context.trace.record(VARIABLE_REASSIGNMENT, expression);
316 if (left instanceof KtArrayAccessExpression) {
317 ExpressionTypingContext contextForResolve = context.replaceScope(scope).replaceBindingTrace(TemporaryBindingTrace.create(
318 context.trace, "trace to resolve array set method for assignment", expression));
319 basic.resolveArrayAccessSetMethod((KtArrayAccessExpression) left, right, contextForResolve, context.trace);
320 }
321 rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
322 components.dataFlowAnalyzer.checkType(binaryOperationType, expression, context.replaceExpectedType(leftType).replaceDataFlowInfo(rightInfo.getDataFlowInfo()));
323 basic.checkLValue(context.trace, context, leftOperand, right);
324 }
325 temporary.commit();
326 return rightInfo.replaceType(checkAssignmentType(type, expression, contextWithExpectedType));
327 }
328
329 @NotNull
330 protected JetTypeInfo visitAssignment(KtBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
331 final ExpressionTypingContext context =
332 contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE).replaceScope(scope).replaceContextDependency(INDEPENDENT);
333 KtExpression leftOperand = expression.getLeft();
334 if (leftOperand instanceof KtAnnotatedExpression) {
335 // We will lose all annotations during deparenthesizing, so we have to resolve them right now
336 components.annotationResolver.resolveAnnotationsWithArguments(
337 scope, ((KtAnnotatedExpression) leftOperand).getAnnotationEntries(), context.trace
338 );
339 }
340 KtExpression left = deparenthesize(leftOperand);
341 KtExpression right = expression.getRight();
342 if (left instanceof KtArrayAccessExpression) {
343 KtArrayAccessExpression arrayAccessExpression = (KtArrayAccessExpression) left;
344 if (right == null) return TypeInfoFactoryKt.noTypeInfo(context);
345 JetTypeInfo typeInfo = basic.resolveArrayAccessSetMethod(arrayAccessExpression, right, context, context.trace);
346 basic.checkLValue(context.trace, context, arrayAccessExpression, right);
347 return typeInfo.replaceType(checkAssignmentType(typeInfo.getType(), expression, contextWithExpectedType));
348 }
349 JetTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(left, context, facade);
350 KotlinType leftType = leftInfo.getType();
351 DataFlowInfo dataFlowInfo = leftInfo.getDataFlowInfo();
352 JetTypeInfo resultInfo;
353 if (right != null) {
354 resultInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(dataFlowInfo).replaceExpectedType(leftType));
355 dataFlowInfo = resultInfo.getDataFlowInfo();
356 KotlinType rightType = resultInfo.getType();
357 if (left != null && leftType != null && rightType != null) {
358 DataFlowValue leftValue = DataFlowValueFactory.createDataFlowValue(left, leftType, context);
359 DataFlowValue rightValue = DataFlowValueFactory.createDataFlowValue(right, rightType, context);
360 // We cannot say here anything new about rightValue except it has the same value as leftValue
361 resultInfo = resultInfo.replaceDataFlowInfo(dataFlowInfo.assign(leftValue, rightValue));
362 }
363 }
364 else {
365 resultInfo = leftInfo;
366 }
367 if (leftType != null && leftOperand != null) { //if leftType == null, some other error has been generated
368 basic.checkLValue(context.trace, context, leftOperand, right);
369 }
370 return resultInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(expression, contextWithExpectedType));
371 }
372
373
374 @Override
375 public JetTypeInfo visitExpression(@NotNull KtExpression expression, ExpressionTypingContext context) {
376 return facade.getTypeInfo(expression, context);
377 }
378
379 @Override
380 public JetTypeInfo visitJetElement(@NotNull KtElement element, ExpressionTypingContext context) {
381 context.trace.report(UNSUPPORTED.on(element, "in a block"));
382 return TypeInfoFactoryKt.noTypeInfo(context);
383 }
384
385 @Override
386 public JetTypeInfo visitWhileExpression(@NotNull KtWhileExpression expression, ExpressionTypingContext context) {
387 return controlStructures.visitWhileExpression(expression, context, true);
388 }
389
390 @Override
391 public JetTypeInfo visitDoWhileExpression(@NotNull KtDoWhileExpression expression, ExpressionTypingContext context) {
392 return controlStructures.visitDoWhileExpression(expression, context, true);
393 }
394
395 @Override
396 public JetTypeInfo visitForExpression(@NotNull KtForExpression expression, ExpressionTypingContext context) {
397 return controlStructures.visitForExpression(expression, context, true);
398 }
399
400 @Override
401 public JetTypeInfo visitAnnotatedExpression(
402 @NotNull KtAnnotatedExpression expression, ExpressionTypingContext data
403 ) {
404 return basic.visitAnnotatedExpression(expression, data, true);
405 }
406
407 @Override
408 public JetTypeInfo visitIfExpression(@NotNull KtIfExpression expression, ExpressionTypingContext context) {
409 return controlStructures.visitIfExpression(expression, context, true);
410 }
411
412 @Override
413 public JetTypeInfo visitWhenExpression(@NotNull KtWhenExpression expression, ExpressionTypingContext context) {
414 return patterns.visitWhenExpression(expression, context, true);
415 }
416
417 @Override
418 public JetTypeInfo visitBlockExpression(@NotNull KtBlockExpression expression, ExpressionTypingContext context) {
419 return components.expressionTypingServices.getBlockReturnedType(expression, context, true);
420 }
421
422 @Override
423 public JetTypeInfo visitLabeledExpression(@NotNull KtLabeledExpression expression, ExpressionTypingContext context) {
424 return basic.visitLabeledExpression(expression, context, true);
425 }
426 }