Error on local classes inside mixins. Closes #2369

Author: Earthcomputer

src/main/kotlin/platform/mixin/inspection/MixinInnerClassInspection.kt

@@ -41,7 +41,7 @@ class MixinInnerClassInspection : MixinInspection() {
     private class Visitor(private val holder: ProblemsHolder) : JavaElementVisitor() {
 
         override fun visitClass(psiClass: PsiClass) {
-            if (PsiUtil.isLocalClass(psiClass)) {
+            if (psiClass.containingClass == null && PsiUtil.isLocalClass(psiClass)) {
                 holder.registerProblem(
                     psiClass.nameIdentifier ?: psiClass,
                     "Local classes are not allowed inside mixins"
@@ -73,7 +73,10 @@ class MixinInnerClassInspection : MixinInspection() {
                     )
                 }
             } else {
-                holder.registerProblem(psiClass, "Inner classes are only allowed if they are also @Mixin classes")
+                holder.registerProblem(
+                    psiClass.nameIdentifier ?: psiClass,
+                    "Inner classes are only allowed if they are also @Mixin classes"
+                )
             }
         }
 

src/test/kotlin/platform/mixin/InnerClassTest.kt

@@ -53,14 +53,19 @@ class InnerClassTest : BaseMixinTest() {
                         private static void stuffInsideAnonymousClassBad() {
                             new Object() {
                                 public void foo() {
-                                    new <error descr="Double nested anonymous classes are not allowed in a @Mixin class">Object() {
-                                    }</error>;
+                                    new <error descr="Double nested anonymous classes are not allowed in a @Mixin class">Object</error>() {
+                                    };
                                 }
 
-                                <error descr="Inner class not allowed inside anonymous classes inside mixins">class ClassInsideAnonymousClass {
-                                }</error>
+                                class <error descr="Inner class not allowed inside anonymous classes inside mixins">ClassInsideAnonymousClass</error> {
+                                }
                             };
                         }
+                        
+                        private static void localClassBad() {
+                            class <error descr="Local classes are not allowed inside mixins">Local</error> {
+                            }
+                        }
                     
                         @Mixin
                         static class GoodInnerMixin {
@@ -72,9 +77,9 @@ class InnerClassTest : BaseMixinTest() {
 
                         }
 
-                        <error descr="Inner classes are only allowed if they are also @Mixin classes">class VeryBadInnerClass {
+                        class <error descr="Inner classes are only allowed if they are also @Mixin classes">VeryBadInnerClass</error> {
 
-                        }</error>
+                        }
 
                     }
                     """,