Move: Warn about moving public declaration to non-public class

#KT-22771 Fixed

compiler/frontend/src/org/jetbrains/kotlin/psi/psiUtil/ktPsiUtil.kt

@@ -431,6 +431,13 @@ fun KtModifierList.visibilityModifierType(): KtModifierKeywordToken? = visibilit
 
 fun KtModifierListOwner.visibilityModifier() = modifierList?.modifierFromTokenSet(KtTokens.VISIBILITY_MODIFIERS)
 
+val KtModifierListOwner.isPublic: Boolean
+    get() {
+        if (this is KtDeclaration && KtPsiUtil.isLocal(this)) return false
+        val visibilityModifier = visibilityModifierType()
+        return visibilityModifier == null || visibilityModifier == KtTokens.PUBLIC_KEYWORD
+    }
+
 fun KtModifierListOwner.visibilityModifierType(): KtModifierKeywordToken? =
     visibilityModifier()?.node?.elementType as KtModifierKeywordToken?
 

idea/src/org/jetbrains/kotlin/idea/refactoring/move/moveDeclarations/moveConflictUtils.kt

@@ -52,10 +52,7 @@ import org.jetbrains.kotlin.idea.util.projectStructure.getModule
 import org.jetbrains.kotlin.idea.util.projectStructure.module
 import org.jetbrains.kotlin.lexer.KtTokens
 import org.jetbrains.kotlin.psi.*
-import org.jetbrains.kotlin.psi.psiUtil.contains
-import org.jetbrains.kotlin.psi.psiUtil.forEachDescendantOfType
-import org.jetbrains.kotlin.psi.psiUtil.getStrictParentOfType
-import org.jetbrains.kotlin.psi.psiUtil.isAncestor
+import org.jetbrains.kotlin.psi.psiUtil.*
 import org.jetbrains.kotlin.renderer.ClassifierNamePolicy
 import org.jetbrains.kotlin.renderer.DescriptorRenderer
 import org.jetbrains.kotlin.renderer.ParameterNameRenderingPolicy
@@ -331,7 +328,9 @@ class MoveConflictChecker(
             val referencedDescriptor = resolutionFacade.resolveToDescriptor(referencedElement)
 
             if (referencedDescriptor is DeclarationDescriptorWithVisibility
-                && referencedDescriptor.visibility == Visibilities.PUBLIC) continue
+                && referencedDescriptor.visibility == Visibilities.PUBLIC
+                && moveTarget is KotlinMoveTargetForExistingElement
+                && moveTarget.targetElement.parentsWithSelf.filterIsInstance<KtClassOrObject>().all { it.isPublic }) continue
 
             val container = element.getUsageContext()
             if (!declarationToContainers.getOrPut(referencedElement) { HashSet<PsiElement>() }.add(container)) continue

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/after/test/PrivateClass.kt

@@ -0,0 +1,7 @@
+package test
+
+private class PrivateClass {
+    class NestedClass {
+        val valInNestedC = 42
+    }
+}

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/after/test/test.kt

@@ -0,0 +1,8 @@
+package test
+
+class SomeClass {
+}
+
+fun main(args: Array<String>) {
+    val test = PrivateClass.NestedClass().valInNestedC
+}

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/before/test/PrivateClass.kt

@@ -0,0 +1,3 @@
+package test
+
+private class PrivateClass

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/before/test/test.kt

@@ -0,0 +1,11 @@
+package test
+
+class SomeClass {
+    class <caret>NestedClass {
+        val valInNestedC = 42
+    }
+}
+
+fun main(args: Array<String>) {
+    val test = SomeClass.NestedClass().valInNestedC
+}

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/conflicts.txt

@@ -0,0 +1 @@
+Variable test uses class NestedClass which will be inaccessible after move

idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/nonInnerToTopLevelPrivateClass.test

@@ -0,0 +1,6 @@
+{
+  "mainFile": "test/test.kt",
+  "type": "MOVE_KOTLIN_NESTED_CLASS",
+  "targetClass": "test.PrivateClass",
+  "withRuntime": "true"
+}

idea/tests/org/jetbrains/kotlin/idea/refactoring/move/MoveTestGenerated.java

@@ -403,6 +403,12 @@ public class MoveTestGenerated extends AbstractMoveTest {
         doTest(fileName);
     }
 
+    @TestMetadata("kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/nonInnerToTopLevelPrivateClass.test")
+    public void testKotlin_moveNestedClass_nonInnerToTopLevelPrivateClass_NonInnerToTopLevelPrivateClass() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/move/kotlin/moveNestedClass/nonInnerToTopLevelPrivateClass/nonInnerToTopLevelPrivateClass.test");
+        doTest(fileName);
+    }
+
     @TestMetadata("kotlin/moveNestedClass/objectToTopLevel/objectToTopLevel.test")
     public void testKotlin_moveNestedClass_objectToTopLevel_ObjectToTopLevel() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("idea/testData/refactoring/move/kotlin/moveNestedClass/objectToTopLevel/objectToTopLevel.test");