Add inspection for when CTOR_HEAD with enforce=POST_INIT doesn't target a field

Author: Earthcomputer

src/main/kotlin/platform/mixin/handlers/injectionPoint/CtorHeadInjectionPoint.kt

@@ -90,7 +90,7 @@ class CtorHeadInjectionPoint : InjectionPoint<PsiElement>() {
         return null
     }
 
-    private enum class EnforceMode {
+    enum class EnforceMode {
         DEFAULT, POST_DELEGATE, POST_INIT
     }
 

src/main/kotlin/platform/mixin/inspection/injector/CtorHeadPostInitInspection.kt

@@ -0,0 +1,87 @@
+/*
+ * Minecraft Development for IntelliJ
+ *
+ * https://mcdev.io/
+ *
+ * Copyright (C) 2024 minecraft-dev
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Lesser General Public License as published
+ * by the Free Software Foundation, version 3.0 only.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package com.demonwav.mcdev.platform.mixin.inspection.injector
+
+import com.demonwav.mcdev.platform.mixin.handlers.MixinAnnotationHandler
+import com.demonwav.mcdev.platform.mixin.handlers.injectionPoint.AtResolver
+import com.demonwav.mcdev.platform.mixin.handlers.injectionPoint.CtorHeadInjectionPoint
+import com.demonwav.mcdev.platform.mixin.inspection.MixinInspection
+import com.demonwav.mcdev.platform.mixin.inspection.fix.AnnotationAttributeFix
+import com.demonwav.mcdev.platform.mixin.util.MethodTargetMember
+import com.demonwav.mcdev.platform.mixin.util.MixinConstants
+import com.demonwav.mcdev.platform.mixin.util.isConstructor
+import com.demonwav.mcdev.util.constantValue
+import com.demonwav.mcdev.util.enumValueOfOrNull
+import com.intellij.codeInspection.ProblemsHolder
+import com.intellij.psi.JavaElementVisitor
+import com.intellij.psi.PsiAnnotation
+import com.intellij.psi.PsiClass
+import com.intellij.psi.PsiElementVisitor
+import com.intellij.psi.PsiModifierList
+import com.intellij.psi.util.parents
+import org.objectweb.asm.Opcodes
+
+class CtorHeadPostInitInspection : MixinInspection() {
+    override fun getStaticDescription() = "Reports when CTOR_HEAD with enforce=POST_INIT doesn't target a field"
+
+    override fun buildVisitor(holder: ProblemsHolder): PsiElementVisitor = object : JavaElementVisitor() {
+        override fun visitAnnotation(annotation: PsiAnnotation) {
+            if (!annotation.hasQualifiedName(MixinConstants.Annotations.AT)) {
+                return
+            }
+            if (annotation.findDeclaredAttributeValue("value")?.constantValue != "CTOR_HEAD") {
+                return
+            }
+
+            val atArgs = annotation.findDeclaredAttributeValue("args") ?: return
+            val enforce = AtResolver.getArgs(annotation)["enforce"]
+                ?.let { enumValueOfOrNull<CtorHeadInjectionPoint.EnforceMode>(it) }
+                ?: CtorHeadInjectionPoint.EnforceMode.DEFAULT
+            if (enforce != CtorHeadInjectionPoint.EnforceMode.POST_INIT) {
+                return
+            }
+
+            val injectorAnnotation = annotation.parents(false)
+                .takeWhile { it !is PsiClass }
+                .filterIsInstance<PsiAnnotation>()
+                .firstOrNull { it.parent is PsiModifierList }
+                ?: return
+            val handler = injectorAnnotation.qualifiedName
+                ?.let { MixinAnnotationHandler.forMixinAnnotation(it, holder.project) }
+                ?: return
+            val targets = handler.resolveTarget(injectorAnnotation).filterIsInstance<MethodTargetMember>()
+
+            if (targets.any {
+                it.classAndMethod.method.isConstructor &&
+                    AtResolver(annotation, it.classAndMethod.clazz, it.classAndMethod.method)
+                        .resolveInstructions()
+                        .any { insn -> insn.insn.previous?.opcode != Opcodes.PUTFIELD }
+            }
+            ) {
+                holder.registerProblem(
+                    atArgs,
+                    "CTOR_HEAD with enforce=POST_INIT doesn't target a field",
+                    AnnotationAttributeFix(annotation, "args" to null)
+                )
+            }
+        }
+    }
+}

src/main/resources/META-INF/plugin.xml

@@ -912,6 +912,14 @@
                          level="WARNING"
                          hasStaticDescription="true"
                          implementationClass="com.demonwav.mcdev.platform.mixin.inspection.injector.UnnecessaryUnsafeInspection"/>
+        <localInspection displayName="CTOR_HEAD with enforce=POST_INIT doesn't target a field"
+                         shortName="CtorHeadPostInit"
+                         groupName="Mixin"
+                         language="JAVA"
+                         enabledByDefault="true"
+                         level="WARNING"
+                         hasStaticDescription="true"
+                         implementationClass="com.demonwav.mcdev.platform.mixin.inspection.injector.CtorHeadPostInitInspection"/>
         <!--endregion-->
 
         <!--region Overwrite Inspections -->