fix for multiple evaluation of expression on multi var declaration

compiler/backend/src/org/jetbrains/jet/codegen/ExpressionCodegen.java

@@ -2809,7 +2809,16 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
 
         JetType initializerType = bindingContext.get(EXPRESSION_TYPE, initializer);
         assert initializerType != null;
-        final ExpressionReceiver initializerAsReceiver = new ExpressionReceiver(initializer, initializerType);
+
+        final Type initializerAsmType = asmType(initializerType);
+
+        final TransientReceiver initializerAsReceiver = new TransientReceiver(initializerType);
+
+        final int tempVarIndex = myFrameMap.enterTemp(initializerAsmType);
+
+        gen(initializer, initializerAsmType);
+        v.store(tempVarIndex, initializerAsmType);
+        final StackValue.Local local = StackValue.local(tempVarIndex, initializerAsmType);
 
         for (final JetMultiDeclarationEntry variableDeclaration : multiDeclaration.getEntries()) {
             initializeLocalVariable(variableDeclaration, new Function<VariableDescriptor, Void>() {
@@ -2819,11 +2828,18 @@ public class ExpressionCodegen extends JetVisitor<StackValue, StackValue> implem
                             bindingContext.get(BindingContext.COMPONENT_RESOLVED_CALL, variableDeclaration);
                     assert resolvedCall != null : "Resolved call is null for " + variableDeclaration.getText();
                     Call call = makeFakeCall(initializerAsReceiver);
-                    invokeFunction(call, StackValue.none(), resolvedCall);
+                    invokeFunction(call, local, resolvedCall);
                     return null;
                 }
             });
         }
+
+        if(initializerAsmType.getSort() == Type.OBJECT || initializerAsmType.getSort() == Type.ARRAY) {
+            v.aconst(null);
+            v.store(tempVarIndex, initializerAsmType);
+        }
+        myFrameMap.leaveTemp(initializerAsmType);
+
         return StackValue.none();
     }
 

compiler/testData/codegen/multiDecl/component.kt

@@ -0,0 +1,17 @@
+class S(val a: String, val b: String) {
+  fun component1() : String = a
+  fun component2() : String = b
+}
+
+fun S.component3() = ((a + b) as java.lang.String).substring(2)
+
+class Tester() {
+  fun box() : String {
+    val (o,k,ok,ok2) = S("O","K")
+    return o + k + ok + ok2
+  }
+
+  fun S.component4() = ((a + b) as java.lang.String).substring(2)
+}
+
+fun box() = Tester().box()

compiler/tests/org/jetbrains/jet/codegen/ComponentGenTest.java

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2010-2012 JetBrains s.r.o.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.jetbrains.jet.codegen;
+
+import org.jetbrains.jet.ConfigurationKind;
+
+/**
+ * This test is separate from MultiDeclTestGenerated because we specifically test generated bytecode
+ * that expression does not evaluated several time
+ */
+public class ComponentGenTest extends CodegenTestCase {
+    public void testComponent() {
+        createEnvironmentWithMockJdkAndIdeaAnnotations(ConfigurationKind.JDK_ONLY);
+        blackBoxFile("/multiDecl/component.kt");
+
+        String asm = generateToText();
+        //System.out.println(asm);
+        final String pattern = "NEW S\n";
+        final int index = asm.indexOf(pattern);
+        asm = asm.substring(index + pattern.length());
+        assertEquals(-1, asm.indexOf(pattern));
+    }
+}

compiler/tests/org/jetbrains/jet/codegen/MultiDeclTestGenerated.java

@@ -13,17 +13,15 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
+
 package org.jetbrains.jet.codegen;
 
-import junit.framework.Assert;
 import junit.framework.Test;
 import junit.framework.TestSuite;
-
-import java.io.File;
 import org.jetbrains.jet.JetTestUtils;
 import org.jetbrains.jet.test.TestMetadata;
 
-import org.jetbrains.jet.codegen.AbstractMultiDeclTestCase;
+import java.io.File;
 
 /** This class is generated by {@link org.jetbrains.jet.codegen.AbstractMultiDeclTestCase}. DO NOT MODIFY MANUALLY */
 @TestMetadata("compiler/testData/codegen/multiDecl")
@@ -37,6 +35,11 @@ public class MultiDeclTestGenerated extends AbstractMultiDeclTestCase {
         blackBoxFileByFullPath("compiler/testData/codegen/multiDecl/ComplexInitializer.kt");
     }
     
+    @TestMetadata("component.kt")
+    public void testComponent() throws Exception {
+        blackBoxFileByFullPath("compiler/testData/codegen/multiDecl/component.kt");
+    }
+    
     @TestMetadata("SimpleVals.kt")
     public void testSimpleVals() throws Exception {
         blackBoxFileByFullPath("compiler/testData/codegen/multiDecl/SimpleVals.kt");