Migration: make header/impl/expect/actual contradictory to each other

compiler/frontend/src/org/jetbrains/kotlin/psi/addRemoveModifier.kt

@@ -129,10 +129,10 @@ private val MODIFIERS_TO_REPLACE = mapOf(
         PROTECTED_KEYWORD to listOf(PUBLIC_KEYWORD, PRIVATE_KEYWORD, INTERNAL_KEYWORD),
         PRIVATE_KEYWORD to listOf(PUBLIC_KEYWORD, PROTECTED_KEYWORD, INTERNAL_KEYWORD),
         INTERNAL_KEYWORD to listOf(PUBLIC_KEYWORD, PROTECTED_KEYWORD, PRIVATE_KEYWORD),
-        HEADER_KEYWORD to listOf(IMPL_KEYWORD, ACTUAL_KEYWORD),
+        HEADER_KEYWORD to listOf(IMPL_KEYWORD, ACTUAL_KEYWORD, EXPECT_KEYWORD),
-        IMPL_KEYWORD to listOf(HEADER_KEYWORD, EXPECT_KEYWORD),
+        IMPL_KEYWORD to listOf(HEADER_KEYWORD, EXPECT_KEYWORD, ACTUAL_KEYWORD),
-        EXPECT_KEYWORD to listOf(IMPL_KEYWORD, ACTUAL_KEYWORD),
+        EXPECT_KEYWORD to listOf(IMPL_KEYWORD, ACTUAL_KEYWORD, HEADER_KEYWORD),
-        ACTUAL_KEYWORD to listOf(HEADER_KEYWORD, EXPECT_KEYWORD)
+        ACTUAL_KEYWORD to listOf(HEADER_KEYWORD, EXPECT_KEYWORD, IMPL_KEYWORD)
 )
 
 private val MODIFIERS_ORDER = listOf(PUBLIC_KEYWORD, PROTECTED_KEYWORD, PRIVATE_KEYWORD, INTERNAL_KEYWORD,

compiler/frontend/src/org/jetbrains/kotlin/resolve/ModifiersChecker.kt

@@ -189,9 +189,12 @@ object ModifierCheckerCore {
         // (see the KEEP https://github.com/Kotlin/KEEP/blob/master/proposals/sealed-class-inheritance.md)
         result += incompatibilityRegister(SEALED_KEYWORD, INNER_KEYWORD)
 
-        // lateinit is incompatible with header
+        // lateinit is incompatible with header / expect
         result += incompatibilityRegister(LATEINIT_KEYWORD, HEADER_KEYWORD, EXPECT_KEYWORD)
 
+        // header / expect / impl / actual are all incompatible
+        result += incompatibilityRegister(HEADER_KEYWORD, EXPECT_KEYWORD, IMPL_KEYWORD, ACTUAL_KEYWORD)
+
         return result
     }
 

compiler/testData/diagnostics/tests/multiplatform/incompatibles.kt

@@ -0,0 +1,13 @@
+// !LANGUAGE: +MultiPlatformProjects
+
+<!DEPRECATED_MODIFIER_FOR_TARGET, INCOMPATIBLE_MODIFIERS!>header<!> <!INCOMPATIBLE_MODIFIERS!>impl<!> class <!NO_ACTUAL_FOR_EXPECT!>First<!>
+
+<!DEPRECATED_MODIFIER_FOR_TARGET, INCOMPATIBLE_MODIFIERS!>header<!> <!INCOMPATIBLE_MODIFIERS!>expect<!> class <!NO_ACTUAL_FOR_EXPECT!>Second<!>
+
+<!DEPRECATED_MODIFIER_FOR_TARGET, INCOMPATIBLE_MODIFIERS!>header<!> <!INCOMPATIBLE_MODIFIERS!>actual<!> class <!NO_ACTUAL_FOR_EXPECT!>Third<!>
+
+<!DEPRECATED_MODIFIER_FOR_TARGET, INCOMPATIBLE_MODIFIERS!>impl<!> <!INCOMPATIBLE_MODIFIERS!>expect<!> class <!NO_ACTUAL_FOR_EXPECT!>Fourth<!>
+
+<!DEPRECATED_MODIFIER_FOR_TARGET, INCOMPATIBLE_MODIFIERS!>impl<!> <!INCOMPATIBLE_MODIFIERS!>actual<!> class <!ACTUAL_WITHOUT_EXPECT!>Fifth<!>
+
+<!INCOMPATIBLE_MODIFIERS!>expect<!> <!INCOMPATIBLE_MODIFIERS!>actual<!> class <!NO_ACTUAL_FOR_EXPECT!>Sixth<!>

compiler/testData/diagnostics/tests/multiplatform/incompatibles.txt

@@ -0,0 +1,8 @@
+package
+
+public final actual class Fifth {
+    public constructor Fifth()
+    public open override /*1*/ /*fake_override*/ fun equals(/*0*/ other: kotlin.Any?): kotlin.Boolean
+    public open override /*1*/ /*fake_override*/ fun hashCode(): kotlin.Int
+    public open override /*1*/ /*fake_override*/ fun toString(): kotlin.String
+}

compiler/tests/org/jetbrains/kotlin/checkers/DiagnosticsTestGenerated.java

@@ -13843,6 +13843,12 @@ public class DiagnosticsTestGenerated extends AbstractDiagnosticsTest {
                 doTest(fileName);
             }
 
+            @TestMetadata("incompatibles.kt")
+            public void testIncompatibles() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/multiplatform/incompatibles.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("modifierApplicability.kt")
             public void testModifierApplicability() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/multiplatform/modifierApplicability.kt");

compiler/tests/org/jetbrains/kotlin/checkers/javac/DiagnosticsUsingJavacTestGenerated.java

@@ -13843,6 +13843,12 @@ public class DiagnosticsUsingJavacTestGenerated extends AbstractDiagnosticsUsing
                 doTest(fileName);
             }
 
+            @TestMetadata("incompatibles.kt")
+            public void testIncompatibles() throws Exception {
+                String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/multiplatform/incompatibles.kt");
+                doTest(fileName);
+            }
+
             @TestMetadata("modifierApplicability.kt")
             public void testModifierApplicability() throws Exception {
                 String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/diagnostics/tests/multiplatform/modifierApplicability.kt");

idea/src/org/jetbrains/kotlin/idea/quickfix/ReplaceModifierFix.kt

@@ -47,11 +47,9 @@ class ReplaceModifierFix(
         when (modifier) {
             KtTokens.HEADER_KEYWORD -> {
                 element.addModifier(KtTokens.EXPECT_KEYWORD)
-                element.removeModifier(KtTokens.HEADER_KEYWORD)
             }
             KtTokens.IMPL_KEYWORD -> {
                 element.addModifier(KtTokens.ACTUAL_KEYWORD)
-                element.removeModifier(KtTokens.IMPL_KEYWORD)
             }
         }
     }