Fix for KT-5150: Accessors for private methods are not generated for get/set conventions

#KT-5150 Fixed

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

@@ -2357,7 +2357,7 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
     }
 
     @NotNull
-    private FunctionDescriptor accessibleFunctionDescriptor(@NotNull ResolvedCall<?> resolvedCall) {
+    protected FunctionDescriptor accessibleFunctionDescriptor(@NotNull ResolvedCall<?> resolvedCall) {
         FunctionDescriptor descriptor = (FunctionDescriptor) resolvedCall.getResultingDescriptor();
         FunctionDescriptor originalIfSamAdapter = SamCodegenUtil.getOriginalIfSamAdapter(descriptor);
         if (originalIfSamAdapter != null) {

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

@@ -911,8 +911,6 @@ public abstract class StackValue {
         private final ExpressionCodegen codegen;
         private final ResolvedCall<FunctionDescriptor> resolvedGetCall;
         private final ResolvedCall<FunctionDescriptor> resolvedSetCall;
-        private final FunctionDescriptor setterDescriptor;
-        private final FunctionDescriptor getterDescriptor;
 
         public CollectionElement(
                 @NotNull CollectionElementReceiver collectionElementReceiver,
@@ -924,10 +922,10 @@ public abstract class StackValue {
             super(type, false, false, collectionElementReceiver, true);
             this.resolvedGetCall = resolvedGetCall;
             this.resolvedSetCall = resolvedSetCall;
-            this.setterDescriptor = resolvedSetCall == null ? null : resolvedSetCall.getResultingDescriptor();
+            this.setter = resolvedSetCall == null ? null :
-            this.getterDescriptor = resolvedGetCall == null ? null : resolvedGetCall.getResultingDescriptor();
+                          codegen.resolveToCallable(codegen.accessibleFunctionDescriptor(resolvedSetCall), false, resolvedSetCall);
-            this.setter = resolvedSetCall == null ? null : codegen.resolveToCallable(setterDescriptor, false, resolvedSetCall);
+            this.getter = resolvedGetCall == null ? null :
-            this.getter = resolvedGetCall == null ? null : codegen.resolveToCallable(getterDescriptor, false, resolvedGetCall);
+                          codegen.resolveToCallable(codegen.accessibleFunctionDescriptor(resolvedGetCall), false, resolvedGetCall);
             this.codegen = codegen;
         }
 

compiler/testData/codegen/box/private/arrayConvention.kt

@@ -0,0 +1,21 @@
+var result = "fail"
+
+private operator fun X.get(name: String) = name + "K"
+private operator fun X.set(name: String, v: String) {
+    result = v
+}
+
+class X {
+    fun test() : String {
+        if (this["O"] != "OK") return "fail 1: ${this["O"]}"
+
+        this["O"] += "K"
+        if (result != "OKK") return "fail 2: ${result}"
+
+        return "OK"
+    }
+}
+
+fun box(): String {
+    return X().test()
+}

compiler/tests/org/jetbrains/kotlin/codegen/generated/BlackBoxCodegenTestGenerated.java

@@ -6422,6 +6422,21 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
         }
     }
 
+    @TestMetadata("compiler/testData/codegen/box/private")
+    @TestDataPath("$PROJECT_ROOT")
+    @RunWith(JUnit3RunnerWithInners.class)
+    public static class Private extends AbstractBlackBoxCodegenTest {
+        public void testAllFilesPresentInPrivate() throws Exception {
+            JetTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/box/private"), Pattern.compile("^(.+)\\.kt$"), true);
+        }
+
+        @TestMetadata("arrayConvention.kt")
+        public void testArrayConvention() throws Exception {
+            String fileName = JetTestUtils.navigationMetadata("compiler/testData/codegen/box/private/arrayConvention.kt");
+            doTest(fileName);
+        }
+    }
+
     @TestMetadata("compiler/testData/codegen/box/privateConstructors")
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)