Generate non-local destructuring declarations as properties

#KT-5620 Fixed
 #KT-15810 Fixed

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

@@ -3439,6 +3439,13 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
 
     @Override
     public StackValue visitDestructuringDeclaration(@NotNull KtDestructuringDeclaration multiDeclaration, StackValue receiver) {
+        return initializeDestructuringDeclaration(multiDeclaration, false);
+    }
+
+    public StackValue initializeDestructuringDeclaration(
+            @NotNull KtDestructuringDeclaration multiDeclaration,
+            boolean asProperty
+    ) {
         KtExpression initializer = multiDeclaration.getInitializer();
         if (initializer == null) return StackValue.none();
 
@@ -3455,7 +3462,7 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
         v.store(tempVarIndex, initializerAsmType);
         StackValue.Local local = StackValue.local(tempVarIndex, initializerAsmType);
 
-        initializeDestructuringDeclarationVariables(multiDeclaration, initializerAsReceiver, local);
+        initializeDestructuringDeclarationVariables(multiDeclaration, initializerAsReceiver, local, asProperty);
 
         if (initializerAsmType.getSort() == Type.OBJECT || initializerAsmType.getSort() == Type.ARRAY) {
             v.aconst(null);
@@ -3470,6 +3477,15 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
             @NotNull KtDestructuringDeclaration destructuringDeclaration,
             @NotNull ReceiverValue receiver,
             @NotNull StackValue receiverStackValue
+    ) {
+        initializeDestructuringDeclarationVariables(destructuringDeclaration, receiver, receiverStackValue, false);
+    }
+
+    private void initializeDestructuringDeclarationVariables(
+            @NotNull KtDestructuringDeclaration destructuringDeclaration,
+            @NotNull ReceiverValue receiver,
+            @NotNull StackValue receiverStackValue,
+            boolean asProperty
     ) {
         for (KtDestructuringDeclarationEntry variableDeclaration : destructuringDeclaration.getEntries()) {
             ResolvedCall<FunctionDescriptor> resolvedCall = bindingContext.get(COMPONENT_RESOLVED_CALL, variableDeclaration);
@@ -3481,7 +3497,21 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
             // Do not call `componentX` for destructuring entry called _
             if (variableDescriptor.getName().isSpecial()) continue;
 
-            initializeLocalVariable(variableDeclaration, invokeFunction(call, resolvedCall, receiverStackValue));
+            if (asProperty && variableDescriptor instanceof PropertyDescriptor) {
+                StackValue.Property propertyValue = intermediateValueForProperty(
+                        (PropertyDescriptor) variableDescriptor,
+                        true,
+                        false,
+                        null,
+                        true,
+                        StackValue.LOCAL_0,
+                        null);
+
+                propertyValue.store(invokeFunction(call, resolvedCall, receiverStackValue), v);
+            }
+            else {
+                initializeLocalVariable(variableDeclaration, invokeFunction(call, resolvedCall, receiverStackValue));
+            }
         }
     }
 

compiler/backend/src/org/jetbrains/kotlin/codegen/MemberCodegen.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2017 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.
@@ -216,6 +216,17 @@ public abstract class MemberCodegen<T extends KtPureElement/* TODO: & KtDeclarat
         else if (declaration instanceof KtTypeAlias) {
             genTypeAlias((KtTypeAlias) declaration);
         }
+        else if (declaration instanceof KtDestructuringDeclarationEntry) {
+            try {
+                propertyCodegen.genDestructuringDeclaration((KtDestructuringDeclarationEntry) declaration);
+            }
+            catch (ProcessCanceledException | CompilationException e) {
+                throw e;
+            }
+            catch (Exception e) {
+                throw new CompilationException("Failed to generate destructuring declaration entry " + declaration.getName(), e, declaration);
+            }
+        }
         else {
             throw new IllegalArgumentException("Unknown parameter: " + declaration);
         }
@@ -466,6 +477,9 @@ public abstract class MemberCodegen<T extends KtPureElement/* TODO: & KtDeclarat
                     initializeProperty(codegen.invoke(), (KtProperty) declaration);
                 }
             }
+            else if (declaration instanceof KtDestructuringDeclaration) {
+                codegen.invoke().initializeDestructuringDeclaration((KtDestructuringDeclaration) declaration, true);
+            }
             else if (declaration instanceof KtAnonymousInitializer) {
                 KtExpression body = ((KtAnonymousInitializer) declaration).getBody();
                 if (body != null) {

compiler/backend/src/org/jetbrains/kotlin/codegen/PropertyCodegen.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2017 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.
@@ -105,6 +105,18 @@ public class PropertyCodegen {
         gen(property, propertyDescriptor, property.getGetter(), property.getSetter());
     }
 
+    public void genDestructuringDeclaration(@NotNull KtDestructuringDeclarationEntry entry) {
+        VariableDescriptor variableDescriptor = bindingContext.get(BindingContext.VARIABLE, entry);
+        if (!(variableDescriptor instanceof PropertyDescriptor)) {
+            throw ExceptionLogger.logDescriptorNotFound(
+                    "Destructuring declaration entry" + entry.getName() + " should have a property descriptor: " + variableDescriptor, entry
+            );
+        }
+
+        PropertyDescriptor propertyDescriptor = (PropertyDescriptor) variableDescriptor;
+        genDestructuringDeclaration(entry, propertyDescriptor);
+    }
+
     public void generateInPackageFacade(@NotNull DeserializedPropertyDescriptor deserializedProperty) {
         assert context instanceof MultifileClassFacadeContext : "should be called only for generating facade: " + context;
         gen(null, deserializedProperty, null, null);
@@ -129,6 +141,19 @@ public class PropertyCodegen {
         }
     }
 
+    private void genDestructuringDeclaration(
+            @Nullable KtDestructuringDeclarationEntry entry,
+            @NotNull PropertyDescriptor descriptor
+    ) {
+        assert kind == OwnerKind.PACKAGE || kind == OwnerKind.IMPLEMENTATION || kind == OwnerKind.DEFAULT_IMPLS
+                : "Generating property with a wrong kind (" + kind + "): " + descriptor;
+
+        genBackingFieldAndAnnotations(entry, descriptor, false);
+
+        generateGetter(entry, descriptor, null);
+        generateSetter(entry, descriptor, null);
+    }
+
     private void genBackingFieldAndAnnotations(
             @Nullable KtNamedDeclaration declaration, @NotNull PropertyDescriptor descriptor, boolean isParameter
     ) {

compiler/backend/src/org/jetbrains/kotlin/codegen/ScriptCodegen.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2016 JetBrains s.r.o.
+ * Copyright 2010-2017 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.
@@ -228,6 +228,11 @@ public class ScriptCodegen extends MemberCodegen<KtScript> {
             else if (declaration instanceof KtClassOrObject) {
                 genClassOrObject((KtClassOrObject) declaration);
             }
+            else if (declaration instanceof KtDestructuringDeclaration) {
+                for (KtDestructuringDeclarationEntry entry : ((KtDestructuringDeclaration) declaration).getEntries()) {
+                    genSimpleMember(entry);
+                }
+            }
         }
     }
 }

compiler/testData/codegen/script/destructuringDeclaration.kts

@@ -0,0 +1,10 @@
+val (abc, def) = A()
+
+val rv = abc + def
+
+class A {
+    operator fun component1() = 123
+    operator fun component2() = 2
+}
+
+// expected: rv: 125

compiler/testData/repl/destructuringDeclaration.repl

@@ -0,0 +1,5 @@
+>>> val (a, b) = listOf(1, 2)
+>>> a
+1
+>>> b
+2

compiler/tests/org/jetbrains/kotlin/codegen/ScriptCodegenTestGenerated.java

@@ -48,6 +48,12 @@ public class ScriptCodegenTestGenerated extends AbstractScriptCodegenTest {
         doTest(fileName);
     }
 
+    @TestMetadata("destructuringDeclaration.kts")
+    public void testDestructuringDeclaration() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/script/destructuringDeclaration.kts");
+        doTest(fileName);
+    }
+
     @TestMetadata("empty.kts")
     public void testEmpty() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/script/empty.kts");

compiler/tests/org/jetbrains/kotlin/repl/ReplInterpreterTestGenerated.java

@@ -48,6 +48,12 @@ public class ReplInterpreterTestGenerated extends AbstractReplInterpreterTest {
         doTest(fileName);
     }
 
+    @TestMetadata("destructuringDeclaration.repl")
+    public void testDestructuringDeclaration() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/repl/destructuringDeclaration.repl");
+        doTest(fileName);
+    }
+
     @TestMetadata("empty.repl")
     public void testEmpty() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/repl/empty.repl");