"field": synthetic variable creation in accessors, codegen changed accordingly, a set of tests, relevant code fix (j2k)

compiler/frontend/src/org/jetbrains/kotlin/descriptors/impl/SyntheticFieldDescriptor.kt

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2010-2015 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.kotlin.descriptors.impl
+
+import org.jetbrains.kotlin.descriptors.PropertyAccessorDescriptor
+import org.jetbrains.kotlin.descriptors.PropertyDescriptor
+import org.jetbrains.kotlin.descriptors.annotations.Annotations
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.psi.JetProperty
+import org.jetbrains.kotlin.resolve.source.toSourceElement
+
+class SyntheticFieldDescriptor private constructor(
+        val propertyDescriptor: PropertyDescriptor,
+        accessorDescriptor: PropertyAccessorDescriptor,
+        property: JetProperty
+): LocalVariableDescriptor(accessorDescriptor, Annotations.EMPTY, SyntheticFieldDescriptor.NAME,
+                           propertyDescriptor.type, propertyDescriptor.isVar, property.toSourceElement()) {
+
+    constructor(accessorDescriptor: PropertyAccessorDescriptor,
+                property: JetProperty): this(accessorDescriptor.correspondingProperty, accessorDescriptor, property)
+
+    override fun getDispatchReceiverParameter() = propertyDescriptor.dispatchReceiverParameter
+
+    companion object {
+        val NAME = Name.identifier("field")
+    }
+}

compiler/frontend/src/org/jetbrains/kotlin/resolve/BodyResolver.java

@@ -25,7 +25,11 @@ import kotlin.jvm.functions.Function1;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 import org.jetbrains.kotlin.descriptors.*;
+import org.jetbrains.kotlin.descriptors.annotations.Annotations;
+import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor;
+import org.jetbrains.kotlin.descriptors.impl.SyntheticFieldDescriptor;
 import org.jetbrains.kotlin.lexer.JetTokens;
+import org.jetbrains.kotlin.name.Name;
 import org.jetbrains.kotlin.psi.*;
 import org.jetbrains.kotlin.psi.psiUtil.PsiUtilPackage;
 import org.jetbrains.kotlin.resolve.calls.CallResolver;
@@ -37,6 +41,7 @@ import org.jetbrains.kotlin.resolve.calls.util.CallMaker;
 import org.jetbrains.kotlin.resolve.lazy.ForceResolveUtil;
 import org.jetbrains.kotlin.resolve.scopes.*;
 import org.jetbrains.kotlin.resolve.scopes.receivers.ReceiverValue;
+import org.jetbrains.kotlin.resolve.source.KotlinSourceElementKt;
 import org.jetbrains.kotlin.types.*;
 import org.jetbrains.kotlin.types.expressions.ExpressionTypingContext;
 import org.jetbrains.kotlin.types.expressions.ExpressionTypingServices;
@@ -649,6 +654,9 @@ public class BodyResolver {
                             trace.record(BindingContext.BACKING_FIELD_REQUIRED, propertyDescriptor); // TODO: this trace?
                         }
                     }
+                    if (descriptor instanceof SyntheticFieldDescriptor) {
+                        trace.record(BindingContext.BACKING_FIELD_REQUIRED, propertyDescriptor);
+                    }
                 }
             }
         });
@@ -766,6 +774,16 @@ public class BodyResolver {
                         trace, innerScope, outerDataFlowInfo, NO_EXPECTED_TYPE, callChecker)
         );
 
+        // Synthetic "field" creation
+        if (functionDescriptor instanceof PropertyAccessorDescriptor) {
+            assert innerScope instanceof WritableScopeStorage : "Expected innerScope as WritableScopeStorage but got " + innerScope;
+            PropertyAccessorDescriptor accessorDescriptor = (PropertyAccessorDescriptor) functionDescriptor;
+            JetProperty property = (JetProperty) function.getParent();
+            SyntheticFieldDescriptor fieldDescriptor = new SyntheticFieldDescriptor(accessorDescriptor, property);
+            WritableScopeStorage innerScopeStorage = (WritableScopeStorage) innerScope;
+            innerScopeStorage.addVariableOrClassDescriptor(fieldDescriptor);
+        }
+
         DataFlowInfo dataFlowInfo = null;
 
         if (beforeBlockBody != null) {