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 kotlin.Pair;
020 import org.jetbrains.annotations.NotNull;
021 import org.jetbrains.annotations.Nullable;
022 import org.jetbrains.kotlin.builtins.KotlinBuiltIns;
023 import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
024 import org.jetbrains.kotlin.diagnostics.DiagnosticFactory1;
025 import org.jetbrains.kotlin.name.Name;
026 import org.jetbrains.kotlin.psi.Call;
027 import org.jetbrains.kotlin.psi.JetExpression;
028 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
029 import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResults;
030 import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver;
031 import org.jetbrains.kotlin.resolve.scopes.receivers.TransientReceiver;
032 import org.jetbrains.kotlin.resolve.validation.SymbolUsageValidator;
033 import org.jetbrains.kotlin.types.JetType;
034 import org.jetbrains.kotlin.util.slicedMap.WritableSlice;
035
036 import javax.inject.Inject;
037 import java.util.Collections;
038
039 import static org.jetbrains.kotlin.diagnostics.Errors.*;
040 import static org.jetbrains.kotlin.resolve.BindingContext.*;
041
042 public class ForLoopConventionsChecker {
043
044 private KotlinBuiltIns builtIns;
045 private SymbolUsageValidator symbolUsageValidator;
046 private FakeCallResolver fakeCallResolver;
047
048 @Inject
049 public void setBuiltIns(@NotNull KotlinBuiltIns builtIns) {
050 this.builtIns = builtIns;
051 }
052
053 @Inject
054 public void setFakeCallResolver(@NotNull FakeCallResolver fakeCallResolver) {
055 this.fakeCallResolver = fakeCallResolver;
056 }
057
058 @Inject
059 public void setSymbolUsageValidator(SymbolUsageValidator symbolUsageValidator) {
060 this.symbolUsageValidator = symbolUsageValidator;
061 }
062
063 @Nullable
064 public JetType checkIterableConvention(@NotNull ExpressionReceiver loopRange, ExpressionTypingContext context) {
065 JetExpression loopRangeExpression = loopRange.getExpression();
066
067 // Make a fake call loopRange.iterator(), and try to resolve it
068 Name iterator = Name.identifier("iterator");
069 Pair<Call, OverloadResolutionResults<FunctionDescriptor>> calls =
070 fakeCallResolver.makeAndResolveFakeCall(loopRange, context, Collections.<JetExpression>emptyList(), iterator,
071 loopRange.getExpression());
072 OverloadResolutionResults<FunctionDescriptor> iteratorResolutionResults = calls.getSecond();
073
074 if (iteratorResolutionResults.isSuccess()) {
075 ResolvedCall<FunctionDescriptor> iteratorResolvedCall = iteratorResolutionResults.getResultingCall();
076 context.trace.record(LOOP_RANGE_ITERATOR_RESOLVED_CALL, loopRangeExpression, iteratorResolvedCall);
077 FunctionDescriptor iteratorFunction = iteratorResolvedCall.getResultingDescriptor();
078
079 symbolUsageValidator.validateCall(iteratorFunction, context.trace, loopRangeExpression);
080
081 JetType iteratorType = iteratorFunction.getReturnType();
082 JetType hasNextType = checkConventionForIterator(context, loopRangeExpression, iteratorType, "hasNext",
083 HAS_NEXT_FUNCTION_AMBIGUITY, HAS_NEXT_MISSING, HAS_NEXT_FUNCTION_NONE_APPLICABLE,
084 LOOP_RANGE_HAS_NEXT_RESOLVED_CALL);
085 if (hasNextType != null && !builtIns.isBooleanOrSubtype(hasNextType)) {
086 context.trace.report(HAS_NEXT_FUNCTION_TYPE_MISMATCH.on(loopRangeExpression, hasNextType));
087 }
088 return checkConventionForIterator(context, loopRangeExpression, iteratorType, "next",
089 NEXT_AMBIGUITY, NEXT_MISSING, NEXT_NONE_APPLICABLE,
090 LOOP_RANGE_NEXT_RESOLVED_CALL);
091 }
092 else {
093 if (iteratorResolutionResults.isAmbiguity()) {
094 context.trace.report(ITERATOR_AMBIGUITY.on(loopRangeExpression, iteratorResolutionResults.getResultingCalls()));
095 }
096 else {
097 context.trace.report(ITERATOR_MISSING.on(loopRangeExpression));
098 }
099 }
100 return null;
101 }
102
103 @Nullable
104 private JetType checkConventionForIterator(
105 @NotNull ExpressionTypingContext context,
106 @NotNull JetExpression loopRangeExpression,
107 @NotNull JetType iteratorType,
108 @NotNull String name,
109 @NotNull DiagnosticFactory1<JetExpression, JetType> ambiguity,
110 @NotNull DiagnosticFactory1<JetExpression, JetType> missing,
111 @NotNull DiagnosticFactory1<JetExpression, JetType> noneApplicable,
112 @NotNull WritableSlice<JetExpression, ResolvedCall<FunctionDescriptor>> resolvedCallKey
113 ) {
114 OverloadResolutionResults<FunctionDescriptor> nextResolutionResults = fakeCallResolver.resolveFakeCall(
115 context, new TransientReceiver(iteratorType), Name.identifier(name), loopRangeExpression);
116 if (nextResolutionResults.isAmbiguity()) {
117 context.trace.report(ambiguity.on(loopRangeExpression, iteratorType));
118 }
119 else if (nextResolutionResults.isNothing()) {
120 context.trace.report(missing.on(loopRangeExpression, iteratorType));
121 }
122 else if (!nextResolutionResults.isSuccess()) {
123 context.trace.report(noneApplicable.on(loopRangeExpression, iteratorType));
124 }
125 else {
126 assert nextResolutionResults.isSuccess();
127 ResolvedCall<FunctionDescriptor> resolvedCall = nextResolutionResults.getResultingCall();
128 context.trace.record(resolvedCallKey, loopRangeExpression, resolvedCall);
129 FunctionDescriptor functionDescriptor = resolvedCall.getResultingDescriptor();
130 symbolUsageValidator.validateCall(functionDescriptor, context.trace, loopRangeExpression);
131 return functionDescriptor.getReturnType();
132 }
133 return null;
134 }
135 }