Fix shadow warning on abstract enum constructors. Closes #2640

Author: Earthcomputer

src/main/kotlin/platform/mixin/inspection/overwrite/OverwriteModifiersInspection.kt

@@ -24,6 +24,7 @@ import com.demonwav.mcdev.platform.mixin.handlers.MixinAnnotationHandler
 import com.demonwav.mcdev.platform.mixin.util.MethodTargetMember
 import com.demonwav.mcdev.platform.mixin.util.MixinConstants.Annotations.OVERWRITE
 import com.demonwav.mcdev.platform.mixin.util.accessLevel
+import com.demonwav.mcdev.platform.mixin.util.bytecodeFriendlyAccessLevel
 import com.demonwav.mcdev.platform.mixin.util.findStubMethod
 import com.demonwav.mcdev.platform.mixin.util.hasModifier
 import com.demonwav.mcdev.platform.mixin.util.internalNameToShortName
@@ -55,7 +56,7 @@ class OverwriteModifiersInspection : OverwriteInspection() {
 
         // Check access modifiers
         val targetAccessLevel = target.method.accessLevel
-        val currentAccessLevel = PsiUtil.getAccessLevel(modifierList)
+        val currentAccessLevel = modifierList.bytecodeFriendlyAccessLevel()
         if (currentAccessLevel < targetAccessLevel) {
             val targetModifier = PsiUtil.getAccessModifier(targetAccessLevel)
             val currentModifier = PsiUtil.getAccessModifier(currentAccessLevel)

src/main/kotlin/platform/mixin/inspection/shadow/ShadowModifiersInspection.kt

@@ -28,6 +28,7 @@ import com.demonwav.mcdev.platform.mixin.util.MixinConstants
 import com.demonwav.mcdev.platform.mixin.util.MixinConstants.Annotations.FINAL
 import com.demonwav.mcdev.platform.mixin.util.MixinTargetMember
 import com.demonwav.mcdev.platform.mixin.util.accessLevel
+import com.demonwav.mcdev.platform.mixin.util.bytecodeFriendlyAccessLevel
 import com.demonwav.mcdev.util.findKeyword
 import com.intellij.codeInsight.intention.AddAnnotationModCommandAction
 import com.intellij.codeInsight.intention.QuickFixFactory
@@ -88,7 +89,7 @@ class ShadowModifiersInspection : MixinInspection() {
 
             // Check access level
             val targetAccessLevel = getTargetAccessLevel(target, shadowModifierList)
-            val shadowAccessLevel = PsiUtil.getAccessLevel(shadowModifierList)
+            val shadowAccessLevel = shadowModifierList.bytecodeFriendlyAccessLevel()
             if (targetAccessLevel != shadowAccessLevel) {
                 val targetModifier = PsiUtil.getAccessModifier(targetAccessLevel)
                 val shadowModifier = PsiUtil.getAccessModifier(shadowAccessLevel)

src/main/kotlin/platform/mixin/util/Mixin.kt

@@ -45,6 +45,9 @@ import com.intellij.psi.PsiDisjunctionType
 import com.intellij.psi.PsiElement
 import com.intellij.psi.PsiIntersectionType
 import com.intellij.psi.PsiLiteralExpression
+import com.intellij.psi.PsiMethod
+import com.intellij.psi.PsiModifier
+import com.intellij.psi.PsiModifierList
 import com.intellij.psi.PsiParameter
 import com.intellij.psi.PsiPrimitiveType
 import com.intellij.psi.PsiType
@@ -53,6 +56,7 @@ import com.intellij.psi.search.GlobalSearchScope
 import com.intellij.psi.util.InheritanceUtil
 import com.intellij.psi.util.PsiModificationTracker
 import com.intellij.psi.util.PsiTypesUtil
+import com.intellij.psi.util.PsiUtil
 import com.intellij.psi.util.TypeConversionUtil
 import org.objectweb.asm.Opcodes
 import org.objectweb.asm.tree.ClassNode
@@ -319,3 +323,20 @@ fun PsiElement.hasNamedLocalVariables(className: String): Boolean {
 
     return true
 }
+
+@PsiUtil.AccessLevel
+fun PsiModifierList.bytecodeFriendlyAccessLevel(): Int {
+    val originalLevel = PsiUtil.getAccessLevel(this)
+
+    val parent = this.parent
+
+    // Constructors are package-local in abstract enums in the bytecode, but not in source
+    if (parent is PsiMethod && parent.isConstructor) {
+        val containingClass = parent.containingClass
+        if (containingClass?.isEnum == true && containingClass.hasModifierProperty(PsiModifier.ABSTRACT)) {
+            return PsiUtil.ACCESS_LEVEL_PACKAGE_LOCAL
+        }
+    }
+
+    return originalLevel
+}