Properly handle the case of backing field access qualified with 'this' reference

compiler/frontend/src/org/jetbrains/jet/lang/cfg/JetFlowInformationProvider.java

@@ -373,7 +373,6 @@ public class JetFlowInformationProvider {
     private boolean checkBackingField(@NotNull VariableContext cxtx, @NotNull JetElement element) {
         VariableDescriptor variableDescriptor = cxtx.variableDescriptor;
         boolean[] error = new boolean[1];
-        if (isCorrectBackingFieldReference((JetElement) element.getParent(), cxtx, error, false)) return false; // this expression has been already checked
         if (!isCorrectBackingFieldReference(element, cxtx, error, true)) return false;
         if (error[0]) return true;
         if (!(variableDescriptor instanceof PropertyDescriptor)) {

compiler/testData/cfg/backingFieldQualifiedWithThis.instructions

@@ -0,0 +1,35 @@
+== Bar ==
+abstract class Bar {
+    abstract var bar : String
+    fun foo() = "foo" + this.$bar
+}
+---------------------
+L0:
+    <START>
+    v(abstract var bar : String)
+L1:
+    <END>                           NEXT:[<SINK>]
+error:
+    <ERROR>                         PREV:[]
+sink:
+    <SINK>                          PREV:[<ERROR>, <END>]
+=====================
+== foo ==
+fun foo() = "foo" + this.$bar
+---------------------
+L0:
+    <START>
+    mark("foo" + this.$bar)
+    mark("foo")
+    r("foo")
+    mark(this.$bar)
+    r(this)
+    r($bar)
+    call(+, plus)
+L1:
+    <END>                      NEXT:[<SINK>]
+error:
+    <ERROR>                    PREV:[]
+sink:
+    <SINK>                     PREV:[<ERROR>, <END>]
+=====================

compiler/testData/cfg/backingFieldQualifiedWithThis.kt

@@ -0,0 +1,4 @@
+abstract class Bar {
+    abstract var bar : String
+    fun foo() = "foo" + this.$bar
+}

compiler/testData/diagnostics/tests/backingField/qualifiedWithThis.kt

@@ -0,0 +1,4 @@
+abstract class Bar {
+    abstract var bar : String
+    fun foo() = "foo" + this.<!NO_BACKING_FIELD_ABSTRACT_PROPERTY!>$bar<!>
+}

compiler/tests/org/jetbrains/jet/cfg/ControlFlowTestGenerated.java

@@ -16,17 +16,14 @@
 
 package org.jetbrains.jet.cfg;
 
-import junit.framework.Assert;
 import junit.framework.Test;
 import junit.framework.TestSuite;
-
-import java.io.File;
-import java.util.regex.Pattern;
 import org.jetbrains.jet.JetTestUtils;
 import org.jetbrains.jet.test.InnerTestClasses;
 import org.jetbrains.jet.test.TestMetadata;
 
-import org.jetbrains.jet.cfg.AbstractControlFlowTest;
+import java.io.File;
+import java.util.regex.Pattern;
 
 /** This class is generated by {@link org.jetbrains.jet.generators.tests.GenerateTests}. DO NOT MODIFY MANUALLY */
 @SuppressWarnings("all")
@@ -77,6 +74,11 @@ public class ControlFlowTestGenerated extends AbstractControlFlowTest {
         doTest("compiler/testData/cfg/backingFieldAccess.kt");
     }
     
+    @TestMetadata("backingFieldQualifiedWithThis.kt")
+    public void testBackingFieldQualifiedWithThis() throws Exception {
+        doTest("compiler/testData/cfg/backingFieldQualifiedWithThis.kt");
+    }
+    
     @TestMetadata("Basic.kt")
     public void testBasic() throws Exception {
         doTest("compiler/testData/cfg/Basic.kt");

compiler/tests/org/jetbrains/jet/checkers/JetDiagnosticsTestGenerated.java

@@ -653,6 +653,11 @@ public class JetDiagnosticsTestGenerated extends AbstractDiagnosticsTestWithEage
                 doTest("compiler/testData/diagnostics/tests/backingField/kt782namespaceLevel.kt");
             }
             
+            @TestMetadata("qualifiedWithThis.kt")
+            public void testQualifiedWithThis() throws Exception {
+                doTest("compiler/testData/diagnostics/tests/backingField/qualifiedWithThis.kt");
+            }
+            
             @TestMetadata("ReadForwardInAnonymous.kt")
             public void testReadForwardInAnonymous() throws Exception {
                 doTest("compiler/testData/diagnostics/tests/backingField/ReadForwardInAnonymous.kt");

idea/testData/quickfix/variables/changeToPropertyName/afterAbstractPropertyThis.kt

@@ -1,5 +1,5 @@
 // "Change '$bar' to 'bar'" "true"
 abstract class Bar {
     abstract var bar : String
-    fun foo() = "foo" + <caret>this.bar
+    fun foo() = "foo" + this.<caret>bar
 }

idea/testData/quickfix/variables/changeToPropertyName/beforeAbstractPropertyThis.kt

@@ -1,5 +1,5 @@
 // "Change '$bar' to 'bar'" "true"
 abstract class Bar {
     abstract var bar : String
-    fun foo() = "foo" + <caret>this.$bar
+    fun foo() = "foo" + this.<caret>$bar
 }