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.descriptors.ReceiverParameterDescriptor;
025    import org.jetbrains.kotlin.diagnostics.DiagnosticFactory1;
026    import org.jetbrains.kotlin.diagnostics.DiagnosticSink;
027    import org.jetbrains.kotlin.name.Name;
028    import org.jetbrains.kotlin.psi.Call;
029    import org.jetbrains.kotlin.psi.KtExpression;
030    import org.jetbrains.kotlin.resolve.calls.checkers.OperatorCallChecker;
031    import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
032    import org.jetbrains.kotlin.resolve.calls.results.OverloadResolutionResults;
033    import org.jetbrains.kotlin.resolve.scopes.receivers.ExpressionReceiver;
034    import org.jetbrains.kotlin.resolve.scopes.receivers.TransientReceiver;
035    import org.jetbrains.kotlin.types.DynamicTypesKt;
036    import org.jetbrains.kotlin.types.ErrorUtils;
037    import org.jetbrains.kotlin.types.KotlinType;
038    import org.jetbrains.kotlin.util.OperatorNameConventions;
039    import org.jetbrains.kotlin.util.slicedMap.WritableSlice;
040    
041    import java.util.Collections;
042    
043    import static org.jetbrains.kotlin.diagnostics.Errors.*;
044    import static org.jetbrains.kotlin.resolve.BindingContext.*;
045    
046    public class ForLoopConventionsChecker {
047        private final KotlinBuiltIns builtIns;
048        private final FakeCallResolver fakeCallResolver;
049    
050        public ForLoopConventionsChecker(
051                @NotNull KotlinBuiltIns builtIns,
052                @NotNull FakeCallResolver fakeCallResolver
053        ) {
054            this.builtIns = builtIns;
055            this.fakeCallResolver = fakeCallResolver;
056        }
057    
058        @Nullable
059        public KotlinType checkIterableConvention(@NotNull ExpressionReceiver loopRange, ExpressionTypingContext context) {
060            KtExpression loopRangeExpression = loopRange.getExpression();
061    
062            // Make a fake call loopRange.iterator(), and try to resolve it
063            Pair<Call, OverloadResolutionResults<FunctionDescriptor>> calls = fakeCallResolver.makeAndResolveFakeCall(
064                    loopRange, context, Collections.<KtExpression>emptyList(), OperatorNameConventions.ITERATOR, loopRangeExpression,
065                    FakeCallKind.ITERATOR, loopRangeExpression
066            );
067            OverloadResolutionResults<FunctionDescriptor> iteratorResolutionResults = calls.getSecond();
068    
069            if (iteratorResolutionResults.isSuccess()) {
070                ResolvedCall<FunctionDescriptor> iteratorResolvedCall = iteratorResolutionResults.getResultingCall();
071                context.trace.record(LOOP_RANGE_ITERATOR_RESOLVED_CALL, loopRangeExpression, iteratorResolvedCall);
072                FunctionDescriptor iteratorFunction = iteratorResolvedCall.getResultingDescriptor();
073    
074                checkIfOperatorModifierPresent(loopRangeExpression, iteratorFunction, context.trace);
075    
076                KotlinType iteratorType = iteratorFunction.getReturnType();
077                //noinspection ConstantConditions
078                KotlinType hasNextType = checkConventionForIterator(
079                        context, loopRangeExpression, iteratorType, OperatorNameConventions.HAS_NEXT,
080                        HAS_NEXT_FUNCTION_AMBIGUITY, HAS_NEXT_MISSING, HAS_NEXT_FUNCTION_NONE_APPLICABLE, LOOP_RANGE_HAS_NEXT_RESOLVED_CALL
081                );
082                if (hasNextType != null && !builtIns.isBooleanOrSubtype(hasNextType)) {
083                    context.trace.report(HAS_NEXT_FUNCTION_TYPE_MISMATCH.on(loopRangeExpression, hasNextType));
084                }
085                return checkConventionForIterator(
086                        context, loopRangeExpression, iteratorType, OperatorNameConventions.NEXT,
087                        NEXT_AMBIGUITY, NEXT_MISSING, NEXT_NONE_APPLICABLE, LOOP_RANGE_NEXT_RESOLVED_CALL
088                );
089            }
090            return null;
091        }
092    
093        private static void checkIfOperatorModifierPresent(KtExpression expression, FunctionDescriptor descriptor, DiagnosticSink sink) {
094            if (ErrorUtils.isError(descriptor)) return;
095            ReceiverParameterDescriptor extensionReceiverParameter = descriptor.getExtensionReceiverParameter();
096            if ((extensionReceiverParameter != null) && (DynamicTypesKt.isDynamic(extensionReceiverParameter.getType()))) return;
097    
098            if (!descriptor.isOperator()) {
099                OperatorCallChecker.Companion.report(expression, descriptor, sink);
100            }
101        }
102    
103        @Nullable
104        private KotlinType checkConventionForIterator(
105                @NotNull ExpressionTypingContext context,
106                @NotNull KtExpression loopRangeExpression,
107                @NotNull KotlinType iteratorType,
108                @NotNull Name name,
109                @NotNull DiagnosticFactory1<KtExpression, KotlinType> ambiguity,
110                @NotNull DiagnosticFactory1<KtExpression, KotlinType> missing,
111                @NotNull DiagnosticFactory1<KtExpression, KotlinType> noneApplicable,
112                @NotNull WritableSlice<KtExpression, ResolvedCall<FunctionDescriptor>> resolvedCallKey
113        ) {
114            OverloadResolutionResults<FunctionDescriptor> nextResolutionResults = fakeCallResolver.resolveFakeCall(
115                    context, new TransientReceiver(iteratorType), name, loopRangeExpression
116            );
117            if (nextResolutionResults.isAmbiguity()) {
118                context.trace.report(ambiguity.on(loopRangeExpression, iteratorType));
119            }
120            else if (nextResolutionResults.isNothing()) {
121                context.trace.report(missing.on(loopRangeExpression, iteratorType));
122            }
123            else if (!nextResolutionResults.isSuccess()) {
124                context.trace.report(noneApplicable.on(loopRangeExpression, iteratorType));
125            }
126            else {
127                assert nextResolutionResults.isSuccess();
128                ResolvedCall<FunctionDescriptor> resolvedCall = nextResolutionResults.getResultingCall();
129                context.trace.record(resolvedCallKey, loopRangeExpression, resolvedCall);
130    
131                FunctionDescriptor functionDescriptor = resolvedCall.getResultingDescriptor();
132                checkIfOperatorModifierPresent(loopRangeExpression, functionDescriptor, context.trace);
133    
134                return functionDescriptor.getReturnType();
135            }
136            return null;
137        }
138    }