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.js.translate.reference;
018
019 import com.google.dart.compiler.backend.js.ast.JsExpression;
020 import org.jetbrains.annotations.NotNull;
021 import org.jetbrains.annotations.Nullable;
022 import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
023 import org.jetbrains.kotlin.js.translate.callTranslator.CallTranslator;
024 import org.jetbrains.kotlin.js.translate.context.TranslationContext;
025 import org.jetbrains.kotlin.js.translate.general.AbstractTranslator;
026 import org.jetbrains.kotlin.js.translate.general.Translation;
027 import org.jetbrains.kotlin.js.translate.utils.BindingUtils;
028 import org.jetbrains.kotlin.psi.KtArrayAccessExpression;
029 import org.jetbrains.kotlin.psi.KtExpression;
030 import org.jetbrains.kotlin.psi.ValueArgument;
031 import org.jetbrains.kotlin.resolve.calls.model.ExpressionValueArgument;
032 import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
033 import org.jetbrains.kotlin.resolve.calls.model.ResolvedValueArgument;
034
035 import java.util.Collections;
036 import java.util.HashMap;
037 import java.util.List;
038 import java.util.Map;
039
040 public class ArrayAccessTranslator extends AbstractTranslator implements AccessTranslator {
041
042 /*package*/
043 static ArrayAccessTranslator newInstance(@NotNull KtArrayAccessExpression expression,
044 @NotNull TranslationContext context) {
045 return new ArrayAccessTranslator(expression, context);
046 }
047
048 @NotNull
049 private final KtArrayAccessExpression expression;
050
051 private ArrayAccessTranslator(@NotNull KtArrayAccessExpression expression, @NotNull TranslationContext context) {
052 super(context);
053 this.expression = expression;
054 }
055
056 @NotNull
057 @Override
058 public JsExpression translateAsGet() {
059 return translateAsGet(getArrayExpression());
060 }
061
062 @NotNull
063 protected JsExpression translateAsGet(@NotNull JsExpression arrayExpression) {
064 return translateAsMethodCall(arrayExpression, null);
065 }
066
067 @NotNull
068 @Override
069 public JsExpression translateAsSet(@NotNull JsExpression setTo) {
070 return translateAsMethodCall(getArrayExpression(), setTo);
071 }
072
073 @NotNull
074 private JsExpression translateAsMethodCall(@NotNull JsExpression arrayExpression, @Nullable JsExpression toSetTo) {
075 boolean isGetter = toSetTo == null;
076 TranslationContext context = context();
077 ResolvedCall<FunctionDescriptor> resolvedCall = BindingUtils.getResolvedCallForArrayAccess(bindingContext(), expression, isGetter);
078 if (!isGetter) {
079 context = contextWithValueParameterAliasInArrayGetAccess(toSetTo);
080 }
081 return CallTranslator.translate(context, resolvedCall, arrayExpression);
082 }
083
084 @NotNull
085 protected JsExpression getArrayExpression() {
086 KtExpression arrayExpression = expression.getArrayExpression();
087 assert arrayExpression != null : "Code with parsing errors shouldn't be translated";
088 return Translation.translateAsExpression(arrayExpression, context());
089 }
090
091 // this is hack for a[b]++ -> a.set(b, a.get(b) + 1). Frontend generate fake expression for a.get(b) + 1.
092 @NotNull
093 private TranslationContext contextWithValueParameterAliasInArrayGetAccess(@NotNull JsExpression toSetTo) {
094 ResolvedCall<FunctionDescriptor> resolvedCall =
095 BindingUtils.getResolvedCallForArrayAccess(bindingContext(), expression, /*isGetter = */ false);
096
097 List<ResolvedValueArgument> arguments = resolvedCall.getValueArgumentsByIndex();
098 if (arguments == null) {
099 throw new IllegalStateException("Failed to arrange value arguments by index: " + resolvedCall.getResultingDescriptor());
100 }
101 ResolvedValueArgument lastArgument = arguments.get(arguments.size() - 1);
102 assert lastArgument instanceof ExpressionValueArgument:
103 "Last argument of array-like setter must be ExpressionValueArgument: " + lastArgument;
104
105 ValueArgument valueArgument = ((ExpressionValueArgument) lastArgument).getValueArgument();
106 assert valueArgument != null;
107
108 KtExpression element = valueArgument.getArgumentExpression();
109 return context().innerContextWithAliasesForExpressions(Collections.singletonMap(element, toSetTo));
110 }
111
112 @NotNull
113 @Override
114 public AccessTranslator getCached() {
115 Map<KtExpression, JsExpression> aliases = new HashMap<KtExpression, JsExpression>();
116
117 JsExpression arrayExpression = context().cacheExpressionIfNeeded(getArrayExpression());
118 aliases.put(expression.getArrayExpression(), arrayExpression);
119
120 for (KtExpression ktExpression : expression.getIndexExpressions()) {
121 JsExpression jsExpression = context().cacheExpressionIfNeeded(Translation.translateAsExpression(ktExpression, context()));
122 aliases.put(ktExpression, jsExpression);
123 }
124
125 return new CachedArrayAccessTranslator(expression, context().innerContextWithAliasesForExpressions(aliases), arrayExpression);
126 }
127
128 private static class CachedArrayAccessTranslator extends ArrayAccessTranslator {
129 @NotNull
130 private final JsExpression arrayExpression;
131
132 protected CachedArrayAccessTranslator(
133 @NotNull KtArrayAccessExpression expression,
134 @NotNull TranslationContext context,
135 @NotNull JsExpression arrayExpression
136 ) {
137 super(expression, context);
138 this.arrayExpression = arrayExpression;
139 }
140
141 @NotNull
142 @Override
143 protected JsExpression getArrayExpression() {
144 return arrayExpression;
145 }
146
147 @NotNull
148 @Override
149 public AccessTranslator getCached() {
150 return this;
151 }
152 }
153 }