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 kotlin.Pair;
022 import org.jetbrains.annotations.NotNull;
023 import org.jetbrains.annotations.Nullable;
024 import org.jetbrains.kotlin.builtins.KotlinBuiltIns;
025 import org.jetbrains.kotlin.descriptors.*;
026 import org.jetbrains.kotlin.diagnostics.Errors;
027 import org.jetbrains.kotlin.lexer.KtTokens;
028 import org.jetbrains.kotlin.name.Name;
029 import org.jetbrains.kotlin.psi.*;
030 import org.jetbrains.kotlin.resolve.BindingContext;
031 import org.jetbrains.kotlin.resolve.BindingContextUtils;
032 import org.jetbrains.kotlin.resolve.TemporaryBindingTrace;
033 import org.jetbrains.kotlin.resolve.calls.context.CallPosition;
034 import org.jetbrains.kotlin.resolve.calls.context.TemporaryTraceAndCache;
035 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
036 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResults;
037 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResultsImpl;
038 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResultsUtil;
039 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowInfo;
040 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowValue;
041 import org.jetbrains.kotlin.resolve.calls.smartcasts.DataFlowValueFactory;
042 import org.jetbrains.kotlin.resolve.scopes.LexicalWritableScope;
043 import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver;
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 KotlinTypeInfo 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 KotlinTypeInfo visitProperty(@NotNull KtProperty property, ExpressionTypingContext typingContext) {
108 Pair<KotlinTypeInfo, VariableDescriptor> typeInfoAndVariableDescriptor = components.localVariableResolver.process(property, typingContext, scope, facade);
109 scope.addVariableDescriptor(typeInfoAndVariableDescriptor.getSecond());
110 return typeInfoAndVariableDescriptor.getFirst();
111 }
112
113 @Override
114 public KotlinTypeInfo visitDestructuringDeclaration(@NotNull KtDestructuringDeclaration multiDeclaration, ExpressionTypingContext context) {
115 components.annotationResolver.resolveAnnotationsWithArguments(scope, multiDeclaration.getModifierList(), context.trace);
116
117 KtExpression initializer = multiDeclaration.getInitializer();
118 if (initializer == null) {
119 context.trace.report(INITIALIZER_REQUIRED_FOR_DESTRUCTURING_DECLARATION.on(multiDeclaration));
120 return TypeInfoFactoryKt.noTypeInfo(context);
121 }
122 ExpressionReceiver expressionReceiver = ExpressionTypingUtils.getExpressionReceiver(
123 facade, initializer, context.replaceExpectedType(NO_EXPECTED_TYPE).replaceContextDependency(INDEPENDENT));
124 KotlinTypeInfo typeInfo = facade.getTypeInfo(initializer, context);
125 if (expressionReceiver == null) {
126 return TypeInfoFactoryKt.noTypeInfo(context);
127 }
128 components.destructuringDeclarationResolver
129 .defineLocalVariablesFromMultiDeclaration(scope, multiDeclaration, expressionReceiver, initializer, context);
130 components.modifiersChecker.withTrace(context.trace).checkModifiersForDestructuringDeclaration(multiDeclaration);
131 components.identifierChecker.checkDeclaration(multiDeclaration, context.trace);
132 return typeInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(multiDeclaration, context));
133 }
134
135 @Override
136 public KotlinTypeInfo visitNamedFunction(@NotNull KtNamedFunction function, ExpressionTypingContext context) {
137 return functions.visitNamedFunction(function, context, true, scope);
138 }
139
140 @Override
141 public KotlinTypeInfo visitClass(@NotNull KtClass klass, ExpressionTypingContext context) {
142 components.localClassifierAnalyzer.processClassOrObject(
143 scope, context.replaceScope(scope).replaceContextDependency(INDEPENDENT),
144 scope.getOwnerDescriptor(),
145 klass);
146 return TypeInfoFactoryKt.createTypeInfo(components.dataFlowAnalyzer.checkStatementType(klass, context), context);
147 }
148
149 @Override
150 public KotlinTypeInfo visitDeclaration(@NotNull KtDeclaration dcl, ExpressionTypingContext context) {
151 return TypeInfoFactoryKt.createTypeInfo(components.dataFlowAnalyzer.checkStatementType(dcl, context), context);
152 }
153
154 @Override
155 public KotlinTypeInfo visitBinaryExpression(@NotNull KtBinaryExpression expression, ExpressionTypingContext context) {
156 KtSimpleNameExpression operationSign = expression.getOperationReference();
157 IElementType operationType = operationSign.getReferencedNameElementType();
158 KotlinTypeInfo result;
159 if (operationType == KtTokens.EQ) {
160 result = visitAssignment(expression, context);
161 }
162 else if (OperatorConventions.ASSIGNMENT_OPERATIONS.containsKey(operationType)) {
163 result = visitAssignmentOperation(expression, context);
164 }
165 else {
166 return facade.getTypeInfo(expression, context);
167 }
168 return components.dataFlowAnalyzer.checkType(result, expression, context);
169 }
170
171 @NotNull
172 protected KotlinTypeInfo visitAssignmentOperation(KtBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
173 //There is a temporary binding trace for an opportunity to resolve set method for array if needed (the initial trace should be used there)
174 TemporaryTraceAndCache temporary = TemporaryTraceAndCache.create(
175 contextWithExpectedType, "trace to resolve array set method for binary expression", expression);
176 ExpressionTypingContext context = contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE)
177 .replaceTraceAndCache(temporary).replaceContextDependency(INDEPENDENT);
178
179 KtSimpleNameExpression operationSign = expression.getOperationReference();
180 IElementType operationType = operationSign.getReferencedNameElementType();
181 KtExpression leftOperand = expression.getLeft();
182 KotlinTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(leftOperand, context, facade);
183 KotlinType leftType = leftInfo.getType();
184
185 KtExpression right = expression.getRight();
186 KtExpression left = leftOperand == null ? null : deparenthesize(leftOperand);
187 if (right == null || left == null) {
188 temporary.commit();
189 return leftInfo.clearType();
190 }
191
192 if (leftType == null) {
193 KotlinTypeInfo rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
194 context.trace.report(UNRESOLVED_REFERENCE.on(operationSign, operationSign));
195 temporary.commit();
196 return rightInfo.clearType();
197 }
198 ExpressionReceiver receiver = ExpressionReceiver.Companion.create(left, leftType, context.trace.getBindingContext());
199
200 // We check that defined only one of '+=' and '+' operations, and call it (in the case '+' we then also assign)
201 // Check for '+='
202 Name name = OperatorConventions.ASSIGNMENT_OPERATIONS.get(operationType);
203 TemporaryTraceAndCache temporaryForAssignmentOperation = TemporaryTraceAndCache.create(
204 context, "trace to check assignment operation like '+=' for", expression);
205 OverloadResolutionResults<FunctionDescriptor> assignmentOperationDescriptors =
206 components.callResolver.resolveBinaryCall(
207 context.replaceTraceAndCache(temporaryForAssignmentOperation).replaceScope(scope),
208 receiver, expression, name
209 );
210 KotlinType assignmentOperationType = OverloadResolutionResultsUtil.getResultingType(assignmentOperationDescriptors,
211 context.contextDependency);
212
213 OverloadResolutionResults<FunctionDescriptor> binaryOperationDescriptors;
214 KotlinType binaryOperationType;
215 TemporaryTraceAndCache temporaryForBinaryOperation = TemporaryTraceAndCache.create(
216 context, "trace to check binary operation like '+' for", expression);
217 TemporaryBindingTrace ignoreReportsTrace = TemporaryBindingTrace.create(context.trace, "Trace for checking assignability");
218 boolean lhsAssignable = basic.checkLValue(ignoreReportsTrace, context, left, right);
219 if (assignmentOperationType == null || lhsAssignable) {
220 // Check for '+'
221 Name counterpartName = OperatorConventions.BINARY_OPERATION_NAMES.get(OperatorConventions.ASSIGNMENT_OPERATION_COUNTERPARTS.get(operationType));
222 binaryOperationDescriptors = components.callResolver.resolveBinaryCall(
223 context.replaceTraceAndCache(temporaryForBinaryOperation).replaceScope(scope),
224 receiver, expression, counterpartName
225 );
226 binaryOperationType = OverloadResolutionResultsUtil.getResultingType(binaryOperationDescriptors, context.contextDependency);
227 }
228 else {
229 binaryOperationDescriptors = OverloadResolutionResultsImpl.nameNotFound();
230 binaryOperationType = null;
231 }
232
233 KotlinType type = assignmentOperationType != null ? assignmentOperationType : binaryOperationType;
234 KotlinTypeInfo rightInfo = leftInfo;
235 if (assignmentOperationDescriptors.isSuccess() && binaryOperationDescriptors.isSuccess()) {
236 // Both 'plus()' and 'plusAssign()' available => ambiguity
237 OverloadResolutionResults<FunctionDescriptor> ambiguityResolutionResults = OverloadResolutionResultsUtil.ambiguity(assignmentOperationDescriptors, binaryOperationDescriptors);
238 context.trace.report(ASSIGN_OPERATOR_AMBIGUITY.on(operationSign, ambiguityResolutionResults.getResultingCalls()));
239 Collection<DeclarationDescriptor> descriptors = Sets.newHashSet();
240 for (ResolvedCall<?> resolvedCall : ambiguityResolutionResults.getResultingCalls()) {
241 descriptors.add(resolvedCall.getResultingDescriptor());
242 }
243 rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
244 context.trace.record(AMBIGUOUS_REFERENCE_TARGET, operationSign, descriptors);
245 }
246 else if (assignmentOperationType != null && (assignmentOperationDescriptors.isSuccess() || !binaryOperationDescriptors.isSuccess())) {
247 // There's 'plusAssign()', so we do a.plusAssign(b)
248 temporaryForAssignmentOperation.commit();
249 if (!KotlinTypeChecker.DEFAULT.equalTypes(components.builtIns.getUnitType(), assignmentOperationType)) {
250 context.trace.report(ASSIGNMENT_OPERATOR_SHOULD_RETURN_UNIT.on(operationSign, assignmentOperationDescriptors.getResultingDescriptor(), operationSign));
251 }
252 }
253 else {
254 // There's only 'plus()', so we try 'a = a + b'
255 temporaryForBinaryOperation.commit();
256 context.trace.record(VARIABLE_REASSIGNMENT, expression);
257 if (left instanceof KtArrayAccessExpression) {
258 ExpressionTypingContext contextForResolve = context.replaceScope(scope).replaceBindingTrace(TemporaryBindingTrace.create(
259 context.trace, "trace to resolve array set method for assignment", expression));
260 basic.resolveArrayAccessSetMethod((KtArrayAccessExpression) left, right, contextForResolve, context.trace);
261 }
262 rightInfo = facade.getTypeInfo(right, context.replaceDataFlowInfo(leftInfo.getDataFlowInfo()));
263
264 KotlinType expectedType = refineTypeFromPropertySetterIfPossible(context.trace.getBindingContext(), leftOperand, leftType);
265
266 components.dataFlowAnalyzer.checkType(binaryOperationType, expression, context.replaceExpectedType(expectedType)
267 .replaceDataFlowInfo(rightInfo.getDataFlowInfo()).replaceCallPosition(new CallPosition.PropertyAssignment(left)));
268 basic.checkLValue(context.trace, context, leftOperand, right);
269 }
270 temporary.commit();
271 return rightInfo.replaceType(checkAssignmentType(type, expression, contextWithExpectedType));
272 }
273
274 @Nullable
275 private static KotlinType refineTypeFromPropertySetterIfPossible(
276 @NotNull BindingContext bindingContext,
277 @Nullable KtElement leftOperand,
278 @Nullable KotlinType leftOperandType
279 ) {
280 VariableDescriptor descriptor = BindingContextUtils.extractVariableFromResolvedCall(bindingContext, leftOperand);
281
282 if (descriptor instanceof PropertyDescriptor) {
283 PropertySetterDescriptor setter = ((PropertyDescriptor) descriptor).getSetter();
284 if (setter != null) return setter.getValueParameters().get(0).getType();
285 }
286
287 return leftOperandType;
288 }
289
290 @NotNull
291 protected KotlinTypeInfo visitAssignment(KtBinaryExpression expression, ExpressionTypingContext contextWithExpectedType) {
292 ExpressionTypingContext context =
293 contextWithExpectedType.replaceExpectedType(NO_EXPECTED_TYPE).replaceScope(scope).replaceContextDependency(INDEPENDENT);
294 KtExpression leftOperand = expression.getLeft();
295 if (leftOperand instanceof KtAnnotatedExpression) {
296 // We will lose all annotations during deparenthesizing, so we have to resolve them right now
297 components.annotationResolver.resolveAnnotationsWithArguments(
298 scope, ((KtAnnotatedExpression) leftOperand).getAnnotationEntries(), context.trace
299 );
300 }
301 KtExpression left = deparenthesize(leftOperand);
302 KtExpression right = expression.getRight();
303 if (left instanceof KtArrayAccessExpression) {
304 KtArrayAccessExpression arrayAccessExpression = (KtArrayAccessExpression) left;
305 if (right == null) return TypeInfoFactoryKt.noTypeInfo(context);
306 KotlinTypeInfo typeInfo = basic.resolveArrayAccessSetMethod(arrayAccessExpression, right, context, context.trace);
307 basic.checkLValue(context.trace, context, arrayAccessExpression, right);
308 return typeInfo.replaceType(checkAssignmentType(typeInfo.getType(), expression, contextWithExpectedType));
309 }
310 KotlinTypeInfo leftInfo = ExpressionTypingUtils.getTypeInfoOrNullType(left, context, facade);
311 KotlinType expectedType = refineTypeFromPropertySetterIfPossible(context.trace.getBindingContext(), leftOperand, leftInfo.getType());
312 DataFlowInfo dataFlowInfo = leftInfo.getDataFlowInfo();
313 KotlinTypeInfo resultInfo;
314 if (right != null) {
315 resultInfo = facade.getTypeInfo(
316 right, context.replaceDataFlowInfo(dataFlowInfo).replaceExpectedType(expectedType).replaceCallPosition(
317 new CallPosition.PropertyAssignment(leftOperand)));
318
319 dataFlowInfo = resultInfo.getDataFlowInfo();
320 KotlinType rightType = resultInfo.getType();
321 if (left != null && expectedType != null && rightType != null) {
322 DataFlowValue leftValue = DataFlowValueFactory.createDataFlowValue(left, expectedType, context);
323 DataFlowValue rightValue = DataFlowValueFactory.createDataFlowValue(right, rightType, context);
324 // We cannot say here anything new about rightValue except it has the same value as leftValue
325 resultInfo = resultInfo.replaceDataFlowInfo(dataFlowInfo.assign(leftValue, rightValue));
326 }
327 }
328 else {
329 resultInfo = leftInfo;
330 }
331 if (expectedType != null && leftOperand != null) { //if expectedType == null, some other error has been generated
332 basic.checkLValue(context.trace, context, leftOperand, right);
333 }
334 return resultInfo.replaceType(components.dataFlowAnalyzer.checkStatementType(expression, contextWithExpectedType));
335 }
336
337
338 @Override
339 public KotlinTypeInfo visitExpression(@NotNull KtExpression expression, ExpressionTypingContext context) {
340 return facade.getTypeInfo(expression, context);
341 }
342
343 @Override
344 public KotlinTypeInfo visitKtElement(@NotNull KtElement element, ExpressionTypingContext context) {
345 context.trace.report(UNSUPPORTED.on(element, "in a block"));
346 return TypeInfoFactoryKt.noTypeInfo(context);
347 }
348
349 @Override
350 public KotlinTypeInfo visitWhileExpression(@NotNull KtWhileExpression expression, ExpressionTypingContext context) {
351 return controlStructures.visitWhileExpression(expression, context, true);
352 }
353
354 @Override
355 public KotlinTypeInfo visitDoWhileExpression(@NotNull KtDoWhileExpression expression, ExpressionTypingContext context) {
356 return controlStructures.visitDoWhileExpression(expression, context, true);
357 }
358
359 @Override
360 public KotlinTypeInfo visitForExpression(@NotNull KtForExpression expression, ExpressionTypingContext context) {
361 return controlStructures.visitForExpression(expression, context, true);
362 }
363
364 @Override
365 public KotlinTypeInfo visitAnnotatedExpression(
366 @NotNull KtAnnotatedExpression expression, ExpressionTypingContext data
367 ) {
368 return basic.visitAnnotatedExpression(expression, data, true);
369 }
370
371 @Override
372 public KotlinTypeInfo visitIfExpression(@NotNull KtIfExpression expression, ExpressionTypingContext context) {
373 return controlStructures.visitIfExpression(expression, context, true);
374 }
375
376 @Override
377 public KotlinTypeInfo visitWhenExpression(@NotNull KtWhenExpression expression, ExpressionTypingContext context) {
378 return patterns.visitWhenExpression(expression, context, true);
379 }
380
381 @Override
382 public KotlinTypeInfo visitBlockExpression(@NotNull KtBlockExpression expression, ExpressionTypingContext context) {
383 return components.expressionTypingServices.getBlockReturnedType(expression, context, true);
384 }
385
386 @Override
387 public KotlinTypeInfo visitLabeledExpression(@NotNull KtLabeledExpression expression, ExpressionTypingContext context) {
388 return basic.visitLabeledExpression(expression, context, true);
389 }
390 }