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.k2js.translate.expression;
018
019
020 import com.google.dart.compiler.backend.js.ast.*;
021 import com.google.dart.compiler.backend.js.ast.metadata.MetadataPackage;
022 import com.intellij.util.SmartList;
023 import org.jetbrains.annotations.NotNull;
024 import org.jetbrains.annotations.Nullable;
025 import org.jetbrains.jet.lang.descriptors.DeclarationDescriptor;
026 import org.jetbrains.jet.lang.descriptors.FunctionDescriptor;
027 import org.jetbrains.jet.lang.descriptors.Modality;
028 import org.jetbrains.jet.lang.descriptors.ValueParameterDescriptor;
029 import org.jetbrains.jet.lang.psi.JetDeclarationWithBody;
030 import org.jetbrains.jet.lang.psi.JetFunctionLiteralExpression;
031 import org.jetbrains.k2js.translate.context.AliasingContext;
032 import org.jetbrains.k2js.translate.context.Namer;
033 import org.jetbrains.k2js.translate.context.TranslationContext;
034 import org.jetbrains.k2js.translate.general.AbstractTranslator;
035 import org.jetbrains.k2js.translate.utils.JsDescriptorUtils;
036 import org.jetbrains.k2js.translate.utils.TranslationUtils;
037
038 import java.util.Collections;
039 import java.util.List;
040
041 import static org.jetbrains.k2js.translate.utils.BindingUtils.getFunctionDescriptor;
042 import static org.jetbrains.k2js.translate.utils.ErrorReportingUtils.message;
043 import static org.jetbrains.k2js.translate.utils.FunctionBodyTranslator.translateFunctionBody;
044 import static org.jetbrains.k2js.translate.utils.JsAstUtils.setParameters;
045
046 public final class FunctionTranslator extends AbstractTranslator {
047 @NotNull
048 public static FunctionTranslator newInstance(@NotNull JetDeclarationWithBody function,
049 @NotNull TranslationContext context) {
050 return new FunctionTranslator(function, context);
051 }
052
053 @NotNull
054 private final TranslationContext functionBodyContext;
055 @NotNull
056 private final JetDeclarationWithBody functionDeclaration;
057 @Nullable
058 private JsName extensionFunctionReceiverName;
059 @NotNull
060 private final JsFunction functionObject;
061 @NotNull
062 private final FunctionDescriptor descriptor;
063
064 private FunctionTranslator(@NotNull JetDeclarationWithBody functionDeclaration, @NotNull TranslationContext context) {
065 super(context);
066 this.descriptor = getFunctionDescriptor(context.bindingContext(), functionDeclaration);
067 this.functionDeclaration = functionDeclaration;
068 this.functionObject = context().getFunctionObject(descriptor);
069 assert this.functionObject.getParameters().isEmpty()
070 : message(descriptor, "Function " + functionDeclaration.getText() + " processed for the second time.");
071 //NOTE: it's important we compute the context before we start the computation
072 this.functionBodyContext = getFunctionBodyContext();
073 }
074
075 @NotNull
076 private TranslationContext getFunctionBodyContext() {
077 AliasingContext aliasingContext;
078 if (isExtensionFunction()) {
079 DeclarationDescriptor expectedReceiverDescriptor = descriptor.getExtensionReceiverParameter();
080 assert expectedReceiverDescriptor != null;
081 extensionFunctionReceiverName = functionObject.getScope().declareName(Namer.getReceiverParameterName());
082 //noinspection ConstantConditions
083 aliasingContext = context().aliasingContext().inner(expectedReceiverDescriptor, extensionFunctionReceiverName.makeRef());
084 }
085 else {
086 aliasingContext = null;
087 }
088 return context().newFunctionBody(functionObject, aliasingContext);
089 }
090
091 @NotNull
092 public JsPropertyInitializer translateAsEcma5PropertyDescriptor() {
093 generateFunctionObject();
094 return TranslationUtils.translateFunctionAsEcma5PropertyDescriptor(functionObject, descriptor, context());
095 }
096
097 @NotNull
098 public JsPropertyInitializer translateAsMethod() {
099 JsName functionName = context().getNameForDescriptor(descriptor);
100 generateFunctionObject();
101 return new JsPropertyInitializer(functionName.makeRef(), functionObject);
102 }
103
104 private void generateFunctionObject() {
105 setParameters(functionObject, translateParameters());
106 translateBody();
107 }
108
109 private void translateBody() {
110 if (!functionDeclaration.hasBody()) {
111 assert descriptor.getModality().equals(Modality.ABSTRACT);
112 return;
113 }
114 functionObject.getBody().getStatements().addAll(translateFunctionBody(descriptor, functionDeclaration, functionBodyContext).getStatements());
115 }
116
117 @NotNull
118 private List<JsParameter> translateParameters() {
119 if (extensionFunctionReceiverName == null && descriptor.getValueParameters().isEmpty()) {
120 return Collections.emptyList();
121 }
122
123 List<JsParameter> jsParameters = new SmartList<JsParameter>();
124 mayBeAddThisParameterForExtensionFunction(jsParameters);
125 addParameters(jsParameters, descriptor, context());
126 return jsParameters;
127 }
128
129 public static void addParameters(List<JsParameter> list, FunctionDescriptor descriptor, TranslationContext context) {
130 for (ValueParameterDescriptor valueParameter : descriptor.getValueParameters()) {
131 JsParameter jsParameter = new JsParameter(context.getNameForDescriptor(valueParameter));
132 MetadataPackage.setHasDefaultValue(jsParameter, valueParameter.hasDefaultValue());
133 list.add(jsParameter);
134 }
135 }
136
137 private void mayBeAddThisParameterForExtensionFunction(@NotNull List<JsParameter> jsParameters) {
138 if (isExtensionFunction()) {
139 assert extensionFunctionReceiverName != null;
140 jsParameters.add(new JsParameter(extensionFunctionReceiverName));
141 }
142 }
143
144 private boolean isExtensionFunction() {
145 return JsDescriptorUtils.isExtension(descriptor) && !(functionDeclaration instanceof JetFunctionLiteralExpression);
146 }
147 }