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.expression;
018    
019    import com.google.dart.compiler.backend.js.ast.JsExpression;
020    import com.google.dart.compiler.backend.js.ast.JsName;
021    import com.google.dart.compiler.backend.js.ast.JsNameRef;
022    import com.google.dart.compiler.backend.js.ast.JsVars;
023    import org.jetbrains.annotations.NotNull;
024    import org.jetbrains.annotations.Nullable;
025    import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
026    import org.jetbrains.kotlin.descriptors.VariableDescriptor;
027    import org.jetbrains.kotlin.js.translate.callTranslator.CallTranslator;
028    import org.jetbrains.kotlin.js.translate.context.TranslationContext;
029    import org.jetbrains.kotlin.js.translate.general.AbstractTranslator;
030    import org.jetbrains.kotlin.js.translate.reference.CallExpressionTranslator;
031    import org.jetbrains.kotlin.js.translate.utils.JsAstUtils;
032    import org.jetbrains.kotlin.psi.KtDestructuringDeclaration;
033    import org.jetbrains.kotlin.psi.KtDestructuringDeclarationEntry;
034    import org.jetbrains.kotlin.resolve.BindingContext;
035    import org.jetbrains.kotlin.resolve.BindingContextUtils;
036    import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
037    
038    import java.util.ArrayList;
039    import java.util.List;
040    
041    import static org.jetbrains.kotlin.js.translate.context.Namer.getCapturedVarAccessor;
042    import static org.jetbrains.kotlin.js.translate.utils.InlineUtils.setInlineCallMetadata;
043    import static org.jetbrains.kotlin.resolve.BindingContextUtils.isVarCapturedInClosure;
044    
045    public class DestructuringDeclarationTranslator extends AbstractTranslator {
046    
047        // if multiObjectName was init, initializer must be null
048        @NotNull
049        public static JsVars translate(
050                @NotNull KtDestructuringDeclaration multiDeclaration,
051                @NotNull JsName multiObjectName,
052                @Nullable JsExpression initializer,
053                @NotNull TranslationContext context
054        ) {
055            return new DestructuringDeclarationTranslator(multiDeclaration, multiObjectName, initializer, context).translate();
056        }
057    
058        @NotNull
059        private final KtDestructuringDeclaration multiDeclaration;
060        @NotNull
061        private final JsName multiObjectName;
062        @Nullable
063        private final JsExpression initializer;
064    
065        private DestructuringDeclarationTranslator(
066                @NotNull KtDestructuringDeclaration multiDeclaration,
067                @NotNull JsName multiObjectName,
068                @Nullable JsExpression initializer,
069                @NotNull TranslationContext context
070        ) {
071            super(context);
072            this.multiDeclaration = multiDeclaration;
073            this.multiObjectName = multiObjectName;
074            this.initializer = initializer;
075        }
076    
077        private JsVars translate() {
078            List<JsVars.JsVar> jsVars = new ArrayList<JsVars.JsVar>();
079            if (initializer != null) {
080                jsVars.add(new JsVars.JsVar(multiObjectName, initializer));
081            }
082    
083            JsNameRef multiObjNameRef = multiObjectName.makeRef();
084            for (KtDestructuringDeclarationEntry entry : multiDeclaration.getEntries()) {
085                ResolvedCall<FunctionDescriptor> entryInitCall =  context().bindingContext().get(BindingContext.COMPONENT_RESOLVED_CALL, entry);
086                assert entryInitCall != null : "Entry init call must be not null";
087                JsExpression entryInitializer = CallTranslator.translate(context(), entryInitCall, multiObjNameRef);
088                FunctionDescriptor candidateDescriptor = entryInitCall.getCandidateDescriptor();
089                if (CallExpressionTranslator.shouldBeInlined(candidateDescriptor)) {
090                    setInlineCallMetadata(entryInitializer, entry, entryInitCall, context());
091                }
092                VariableDescriptor descriptor = BindingContextUtils.getNotNull( context().bindingContext(), BindingContext.VARIABLE, entry);
093                JsName name =  context().getNameForDescriptor(descriptor);
094                if (isVarCapturedInClosure(context().bindingContext(), descriptor)) {
095                    JsNameRef alias = getCapturedVarAccessor(name.makeRef());
096                    entryInitializer = JsAstUtils.wrapValue(alias, entryInitializer);
097                }
098    
099                jsVars.add(new JsVars.JsVar(name, entryInitializer));
100            }
101            return new JsVars(jsVars, true);
102        }
103    }