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 org.jetbrains.kotlin.builtins.KotlinBuiltIns;
020    import org.jetbrains.kotlin.js.backend.ast.JsExpression;
021    import org.jetbrains.kotlin.js.backend.ast.JsName;
022    import org.jetbrains.kotlin.js.backend.ast.JsNameRef;
023    import org.jetbrains.kotlin.js.backend.ast.JsVars;
024    import org.jetbrains.annotations.NotNull;
025    import org.jetbrains.annotations.Nullable;
026    import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
027    import org.jetbrains.kotlin.descriptors.VariableDescriptor;
028    import org.jetbrains.kotlin.js.translate.callTranslator.CallTranslator;
029    import org.jetbrains.kotlin.js.translate.context.TranslationContext;
030    import org.jetbrains.kotlin.js.translate.general.AbstractTranslator;
031    import org.jetbrains.kotlin.js.translate.reference.CallExpressionTranslator;
032    import org.jetbrains.kotlin.js.translate.utils.JsAstUtils;
033    import org.jetbrains.kotlin.psi.KtDestructuringDeclaration;
034    import org.jetbrains.kotlin.psi.KtDestructuringDeclarationEntry;
035    import org.jetbrains.kotlin.resolve.BindingContext;
036    import org.jetbrains.kotlin.resolve.BindingContextUtils;
037    import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall;
038    import org.jetbrains.kotlin.types.KotlinType;
039    
040    import java.util.ArrayList;
041    import java.util.List;
042    
043    import static org.jetbrains.kotlin.js.translate.context.Namer.getCapturedVarAccessor;
044    import static org.jetbrains.kotlin.js.translate.utils.InlineUtils.setInlineCallMetadata;
045    import static org.jetbrains.kotlin.resolve.BindingContextUtils.isVarCapturedInClosure;
046    
047    public class DestructuringDeclarationTranslator extends AbstractTranslator {
048    
049        // if multiObjectName was init, initializer must be null
050        @NotNull
051        public static JsVars translate(
052                @NotNull KtDestructuringDeclaration multiDeclaration,
053                @NotNull JsName multiObjectName,
054                @Nullable JsExpression initializer,
055                @NotNull TranslationContext context
056        ) {
057            return new DestructuringDeclarationTranslator(multiDeclaration, multiObjectName, initializer, context).translate();
058        }
059    
060        @NotNull
061        private final KtDestructuringDeclaration multiDeclaration;
062        @NotNull
063        private final JsName multiObjectName;
064        @Nullable
065        private final JsExpression initializer;
066    
067        private DestructuringDeclarationTranslator(
068                @NotNull KtDestructuringDeclaration multiDeclaration,
069                @NotNull JsName multiObjectName,
070                @Nullable JsExpression initializer,
071                @NotNull TranslationContext context
072        ) {
073            super(context);
074            this.multiDeclaration = multiDeclaration;
075            this.multiObjectName = multiObjectName;
076            this.initializer = initializer;
077        }
078    
079        private JsVars translate() {
080            List<JsVars.JsVar> jsVars = new ArrayList<JsVars.JsVar>();
081            if (initializer != null) {
082                jsVars.add(new JsVars.JsVar(multiObjectName, initializer));
083            }
084    
085            JsNameRef multiObjNameRef = multiObjectName.makeRef();
086            for (KtDestructuringDeclarationEntry entry : multiDeclaration.getEntries()) {
087                VariableDescriptor descriptor = BindingContextUtils.getNotNull( context().bindingContext(), BindingContext.VARIABLE, entry);
088                // Do not call `componentX` for destructuring entry called _
089                if (descriptor.getName().isSpecial()) continue;
090    
091                ResolvedCall<FunctionDescriptor> entryInitCall =  context().bindingContext().get(BindingContext.COMPONENT_RESOLVED_CALL, entry);
092                assert entryInitCall != null : "Entry init call must be not null";
093                JsExpression entryInitializer = CallTranslator.translate(context(), entryInitCall, multiObjNameRef);
094                FunctionDescriptor candidateDescriptor = entryInitCall.getCandidateDescriptor();
095                if (CallExpressionTranslator.shouldBeInlined(candidateDescriptor, context())) {
096                    setInlineCallMetadata(entryInitializer, entry, entryInitCall, context());
097                }
098    
099                KotlinType returnType = candidateDescriptor.getReturnType();
100                if (returnType != null && KotlinBuiltIns.isCharOrNullableChar(returnType) && !KotlinBuiltIns.isCharOrNullableChar(descriptor.getType())) {
101                    entryInitializer = JsAstUtils.charToBoxedChar(entryInitializer);
102                }
103    
104                JsName name =  context().getNameForDescriptor(descriptor);
105                if (isVarCapturedInClosure(context().bindingContext(), descriptor)) {
106                    JsNameRef alias = getCapturedVarAccessor(name.makeRef());
107                    entryInitializer = JsAstUtils.wrapValue(alias, entryInitializer);
108                }
109    
110                jsVars.add(new JsVars.JsVar(name, entryInitializer));
111            }
112            return new JsVars(jsVars, true);
113        }
114    }