Annotation parameters now cannot be mutable #KT-12367 Fixed

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/Errors.java

@@ -155,6 +155,7 @@ public interface Errors {
 
     DiagnosticFactory0<KtSuperTypeList> SUPERTYPES_FOR_ANNOTATION_CLASS = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory0<KtParameter> MISSING_VAL_ON_ANNOTATION_PARAMETER = DiagnosticFactory0.create(ERROR);
+    DiagnosticFactory0<KtParameter> VAR_ANNOTATION_PARAMETER = DiagnosticFactory0.create(ERROR, VAL_OR_VAR_NODE);
     DiagnosticFactory0<KtCallExpression> ANNOTATION_CLASS_CONSTRUCTOR_CALL = DiagnosticFactory0.create(ERROR);
     DiagnosticFactory1<KtAnnotationEntry, DeclarationDescriptor> NOT_AN_ANNOTATION_CLASS = DiagnosticFactory1.create(ERROR);
     DiagnosticFactory0<PsiElement> ANNOTATION_CLASS_WITH_BODY = DiagnosticFactory0.create(ERROR);

compiler/frontend/src/org/jetbrains/kotlin/diagnostics/rendering/DefaultErrorMessages.java

@@ -679,6 +679,7 @@ public class DefaultErrorMessages {
 
         MAP.put(SUPERTYPES_FOR_ANNOTATION_CLASS, "Annotation class cannot have supertypes");
         MAP.put(MISSING_VAL_ON_ANNOTATION_PARAMETER, "'val' keyword is missing on annotation parameter");
+        MAP.put(VAR_ANNOTATION_PARAMETER, "An annotation parameter cannot be 'var'");
         MAP.put(ANNOTATION_CLASS_CONSTRUCTOR_CALL, "Annotation class cannot be instantiated");
         MAP.put(NOT_AN_ANNOTATION_CLASS, "''{0}'' is not an annotation class", NAME);
         MAP.put(ANNOTATION_CLASS_WITH_BODY, "Body is not allowed for annotation class");

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

@@ -368,6 +368,9 @@ class DeclarationsChecker(
             if (!parameter.hasValOrVar()) {
                 trace.report(MISSING_VAL_ON_ANNOTATION_PARAMETER.on(parameter))
             }
+            else if (parameter.isMutable) {
+                trace.report(VAR_ANNOTATION_PARAMETER.on(parameter))
+            }
         }
     }
 

compiler/testData/diagnostics/tests/annotations/kt1886annotationBody.kt

@@ -22,7 +22,7 @@ annotation class Annotation1() <!ANNOTATION_CLASS_WITH_BODY!>{}<!>
 
 annotation class Annotation7(val name: String) <!ANNOTATION_CLASS_WITH_BODY!>{}<!>
 
-annotation class Annotation8(var name: String = "") <!ANNOTATION_CLASS_WITH_BODY!>{}<!>
+annotation class Annotation8(<!VAR_ANNOTATION_PARAMETER!>var<!> name: String = "") <!ANNOTATION_CLASS_WITH_BODY!>{}<!>
 
 annotation class Annotation9(val name: String)
 

compiler/testData/diagnostics/tests/annotations/missingValOnParameter.kt

@@ -1,5 +1,5 @@
 annotation class Ann(
         val a: Int,
-        var b: Int,
+        <!VAR_ANNOTATION_PARAMETER!>var<!> b: Int,
         <!MISSING_VAL_ON_ANNOTATION_PARAMETER!>c: String<!>
         )

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

@@ -74,5 +74,12 @@ class ChangeVariableMutabilityFix(element: KtValVarKeywordOwner, private val mak
                 }
             }
         }
+
+        val VAR_ANNOTATION_PARAMETER_FACTORY: KotlinSingleIntentionActionFactory = object: KotlinSingleIntentionActionFactory() {
+            override fun createAction(diagnostic: Diagnostic): IntentionAction? {
+                val element = diagnostic.psiElement as KtParameter
+                return ChangeVariableMutabilityFix(element, false)
+            }
+        }
     }
 }

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

@@ -171,6 +171,7 @@ class QuickFixRegistrar : QuickFixContributor {
         VAL_REASSIGNMENT.registerFactory(ChangeVariableMutabilityFix.VAL_REASSIGNMENT_FACTORY)
         CAPTURED_VAL_INITIALIZATION.registerFactory(ChangeVariableMutabilityFix.CAPTURED_VAL_INITIALIZATION_FACTORY)
         VAR_OVERRIDDEN_BY_VAL.registerFactory(ChangeVariableMutabilityFix.VAR_OVERRIDDEN_BY_VAL_FACTORY)
+        VAR_ANNOTATION_PARAMETER.registerFactory(ChangeVariableMutabilityFix.VAR_ANNOTATION_PARAMETER_FACTORY)
 
         VAL_OR_VAR_ON_FUN_PARAMETER.registerFactory(RemoveValVarFromParameterFix)
         VAL_OR_VAR_ON_LOOP_PARAMETER.registerFactory(RemoveValVarFromParameterFix)