Properly handle ctor of mixed in inner classes

Author: RedNesto

src/main/kotlin/com/demonwav/mcdev/platform/mixin/inspection/injector/InjectorType.kt

@@ -18,6 +18,7 @@ import com.demonwav.mcdev.platform.mixin.util.callbackInfoType
 import com.demonwav.mcdev.util.Parameter
 import com.demonwav.mcdev.util.constantStringValue
 import com.demonwav.mcdev.util.constantValue
+import com.intellij.lang.jvm.JvmModifier
 import com.intellij.psi.JavaPsiFacade
 import com.intellij.psi.PsiAnnotation
 import com.intellij.psi.PsiAnnotationOwner
@@ -38,6 +39,16 @@ enum class InjectorType(private val annotation: String) {
 
             val result = ArrayList<ParameterGroup>()
 
+            if (targetMethod.isConstructor) {
+                val containingClass = targetMethod.containingClass
+                val outerClass = containingClass?.containingClass
+                if (outerClass != null && !containingClass.hasModifier(JvmModifier.STATIC)) {
+                    val outerClassType = JavaPsiFacade.getElementFactory(outerClass.project).createType(outerClass)
+                    // Inner classes ctors take their outer class as first parameter (required)
+                    result.add(ParameterGroup(listOf(Parameter("outer", outerClassType))))
+                }
+            }
+
             // Parameters from injected method (optional)
             result.add(ParameterGroup(collectTargetMethodParameters(targetMethod), required = false, default = true))
 

src/test/kotlin/com/demonwav/mcdev/platform/mixin/InvalidInjectorMethodSignatureInspectionTest.kt

@@ -0,0 +1,131 @@
+/*
+ * Minecraft Dev for IntelliJ
+ *
+ * https://minecraftdev.org
+ *
+ * Copyright (c) 2020 minecraft-dev
+ *
+ * MIT License
+ */
+
+package com.demonwav.mcdev.platform.mixin
+
+import com.demonwav.mcdev.framework.EdtInterceptor
+import com.demonwav.mcdev.platform.mixin.inspection.injector.InvalidInjectorMethodSignatureInspection
+import org.intellij.lang.annotations.Language
+import org.junit.jupiter.api.DisplayName
+import org.junit.jupiter.api.Test
+import org.junit.jupiter.api.extension.ExtendWith
+
+@ExtendWith(EdtInterceptor::class)
+@DisplayName("Invalid Injector Method Signature Inspection Test")
+class InvalidInjectorMethodSignatureInspectionTest : BaseMixinTest() {
+
+    private fun doTest(@Language("JAVA") code: String) {
+        buildProject {
+            dir("test") {
+                java(
+                    "MixedInOuter.java",
+                    """
+                    package test;
+                    
+                    import java.lang.String;
+
+                    class MixedInOuter {
+                        public class MixedInInner {
+                            public MixedInInner() {
+                            }
+                            
+                            public MixedInInner(String string) {
+                            }
+                        }
+                        
+                        public static class MixedInStaticInner {
+                            public MixedInStaticInner() {
+                            }
+                            
+                            public MixedInStaticInner(String string) {
+                            }
+                        }
+                    }
+                    """,
+                    configure = false
+                )
+                java("TestMixin.java", code)
+            }
+        }
+
+        fixture.enableInspections(InvalidInjectorMethodSignatureInspection::class)
+        fixture.checkHighlighting(false, false, false)
+    }
+
+    @Test
+    @DisplayName("Inner Ctor @Inject Parameters")
+    fun innerCtorInjectParameters() {
+        doTest(
+            """
+            package test;
+
+            import org.spongepowered.asm.mixin.Mixin;
+            import org.spongepowered.asm.mixin.injection.At;
+            import org.spongepowered.asm.mixin.injection.Inject;
+            import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+            @Mixin(MixedInOuter.MixedInInner.class)
+            public class TestMixin {
+
+                @Inject(method = "<init>", at = @At("RETURN"))
+                private void injectCtor(MixedInOuter outer, CallbackInfo ci) {
+                }
+
+                @Inject(method = "<init>", at = @At("RETURN"))
+                private void injectCtor<error descr="Method parameters do not match expected parameters for @Inject">(CallbackInfo ci)</error> {
+                }
+
+                @Inject(method = "<init>(Ljava/lang/String;)V", at = @At("RETURN"))
+                private void injectCtor(MixedInOuter outer, String string, CallbackInfo ci) {
+                }
+
+                @Inject(method = "<init>(Ljava/lang/String;)V", at = @At("RETURN"))
+                private void injectCtor<error descr="Method parameters do not match expected parameters for @Inject">(String string, CallbackInfo ci)</error> {
+                }
+            }
+            """
+        )
+    }
+
+    @Test
+    @DisplayName("Static Inner Ctor @Inject Parameters")
+    fun staticInnerCtorInjectParameters() {
+        doTest(
+            """
+            package test;
+
+            import org.spongepowered.asm.mixin.Mixin;
+            import org.spongepowered.asm.mixin.injection.At;
+            import org.spongepowered.asm.mixin.injection.Inject;
+            import org.spongepowered.asm.mixin.injection.callback.CallbackInfo;
+
+            @Mixin(MixedInOuter.MixedInStaticInner.class)
+            public class TestMixin {
+
+                @Inject(method = "<init>", at = @At("RETURN"))
+                private void injectCtor<error descr="Method parameters do not match expected parameters for @Inject">(MixedInOuter outer, CallbackInfo ci)</error> {
+                }
+
+                @Inject(method = "<init>", at = @At("RETURN"))
+                private void injectCtor(CallbackInfo ci) {
+                }
+
+                @Inject(method = "<init>(Ljava/lang/String;)V", at = @At("RETURN"))
+                private void injectCtor<error descr="Method parameters do not match expected parameters for @Inject">(MixedInOuter outer, String string, CallbackInfo ci)</error> {
+                }
+
+                @Inject(method = "<init>(Ljava/lang/String;)V", at = @At("RETURN"))
+                private void injectCtor(String string, CallbackInfo ci) {
+                }
+            }
+            """
+        )
+    }
+}