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.resolve.calls.autocasts;
018
019 import com.google.common.collect.Lists;
020 import org.jetbrains.annotations.NotNull;
021 import org.jetbrains.jet.lang.resolve.BindingContext;
022 import org.jetbrains.jet.lang.resolve.BindingTrace;
023 import org.jetbrains.jet.lang.resolve.scopes.receivers.*;
024 import org.jetbrains.jet.lang.types.JetType;
025
026 import java.util.Collections;
027 import java.util.List;
028
029 import static org.jetbrains.jet.lang.diagnostics.Errors.AUTOCAST_IMPOSSIBLE;
030 import static org.jetbrains.jet.lang.resolve.BindingContext.AUTOCAST;
031 import static org.jetbrains.jet.lang.resolve.BindingContext.EXPRESSION_TYPE;
032
033 public class AutoCastUtils {
034
035 private AutoCastUtils() {}
036
037 /**
038 * @return variants @param receiverToCast may be cast to according to @param dataFlowInfo, @param receiverToCast itself is NOT included
039 */
040 public static List<ReceiverValue> getAutoCastVariants(
041 @NotNull final BindingContext bindingContext,
042 @NotNull final DataFlowInfo dataFlowInfo, @NotNull ReceiverValue receiverToCast
043 ) {
044 return receiverToCast.accept(new ReceiverValueVisitor<List<ReceiverValue>, Object>() {
045 @Override
046 public List<ReceiverValue> visitNoReceiver(ReceiverValue noReceiver, Object data) {
047 return Collections.emptyList();
048 }
049
050 @Override
051 public List<ReceiverValue> visitTransientReceiver(TransientReceiver receiver, Object data) {
052 return Collections.emptyList();
053 }
054
055 @Override
056 public List<ReceiverValue> visitExtensionReceiver(ExtensionReceiver receiver, Object data) {
057 return castThis(dataFlowInfo, receiver);
058 }
059
060 @Override
061 public List<ReceiverValue> visitClassReceiver(ClassReceiver receiver, Object data) {
062 return castThis(dataFlowInfo, receiver);
063 }
064
065 @Override
066 public List<ReceiverValue> visitScriptReceiver(ScriptReceiver receiver, Object data) {
067 return Collections.emptyList();
068 }
069
070 @Override
071 public List<ReceiverValue> visitExpressionReceiver(ExpressionReceiver receiver, Object data) {
072 DataFlowValue dataFlowValue = DataFlowValueFactory.INSTANCE.createDataFlowValue(receiver.getExpression(), receiver.getType(),
073 bindingContext);
074 List<ReceiverValue> result = Lists.newArrayList();
075 for (JetType possibleType : dataFlowInfo.getPossibleTypes(dataFlowValue)) {
076 result.add(new AutoCastReceiver(receiver, possibleType, dataFlowValue.isStableIdentifier()));
077 }
078 return result;
079 }
080 }, null);
081 }
082
083 private static List<ReceiverValue> castThis(@NotNull DataFlowInfo dataFlowInfo, @NotNull ThisReceiver receiver) {
084 assert receiver.exists();
085 List<ReceiverValue> result = Lists.newArrayList();
086 for (JetType possibleType : dataFlowInfo.getPossibleTypes(DataFlowValueFactory.INSTANCE.createDataFlowValue(receiver))) {
087 result.add(new AutoCastReceiver(receiver, possibleType, true));
088 }
089 return result;
090 }
091
092 public static void recordAutoCastIfNecessary(ReceiverValue receiver, @NotNull BindingTrace trace) {
093 if (receiver instanceof AutoCastReceiver) {
094 AutoCastReceiver autoCastReceiver = (AutoCastReceiver) receiver;
095 ReceiverValue original = autoCastReceiver.getOriginal();
096 if (original instanceof ExpressionReceiver) {
097 ExpressionReceiver expressionReceiver = (ExpressionReceiver) original;
098 if (autoCastReceiver.canCast()) {
099 trace.record(AUTOCAST, expressionReceiver.getExpression(), autoCastReceiver.getType());
100 trace.record(EXPRESSION_TYPE, expressionReceiver.getExpression(), autoCastReceiver.getType());
101 }
102 else {
103 trace.report(AUTOCAST_IMPOSSIBLE.on(expressionReceiver.getExpression(), autoCastReceiver.getType(), expressionReceiver.getExpression().getText()));
104 }
105 }
106 else {
107 assert autoCastReceiver.canCast() : "A non-expression receiver must always be autocastabe: " + original;
108 }
109 }
110 }
111 }