PSI equivalence bug for method type parameters

java/java-impl/src/com/intellij/psi/impl/PsiClassImplUtil.java

@@ -946,16 +946,35 @@ public class PsiClassImplUtil {
     return aClass1 != null && aClass2 != null && field.getManager().areElementsEquivalent(aClass1, aClass2);
   }
 
-  public static boolean isMethodEquivalentTo(PsiMethod method, PsiElement another) {
+  public static boolean isMethodEquivalentTo(PsiMethod method1, PsiElement another) {
     if (!(another instanceof PsiMethod)) return false;
     PsiMethod method2 = (PsiMethod)another;
-    String name1 = method.getName();
+    String name1 = method1.getName();
     if (!another.isValid()) return false;
     String name2 = method2.getName();
     if (!name1.equals(name2)) return false;
-    PsiClass aClass1 = method.getContainingClass();
+    PsiClass aClass1 = method1.getContainingClass();
     PsiClass aClass2 = method2.getContainingClass();
-    return aClass1 != null && aClass2 != null && method.getManager().areElementsEquivalent(aClass1, aClass2) &&
-           MethodSignatureUtil.areSignaturesEqual(method.getSignature(PsiSubstitutor.EMPTY), method2.getSignature(PsiSubstitutor.EMPTY));
+    PsiManager manager = method1.getManager();
+    if (!(aClass1 != null && aClass2 != null && manager.areElementsEquivalent(aClass1, aClass2))) return false;
+
+    PsiParameter[] parameters1 = method1.getParameterList().getParameters();
+    PsiParameter[] parameters2 = method2.getParameterList().getParameters();
+    if (parameters1.length != parameters2.length) return false;
+    for (int i = 0; i < parameters1.length; i++) {
+      PsiParameter parameter1 = parameters1[i];
+      PsiParameter parameter2 = parameters2[i];
+      PsiType type1 = parameter1.getType();
+      PsiType type2 = parameter2.getType();
+      if (!(type1 instanceof PsiClassType) || !(type2 instanceof PsiClassType)) {
+        if (!type1.equals(type2)) return false;
+      }
+      else {
+        PsiClass class1 = ((PsiClassType)type1).resolve();
+        PsiClass class2 = ((PsiClassType)type2).resolve();
+        if (!manager.areElementsEquivalent(class1, class2)) return false;
+      }
+    }
+    return true;
   }
 }

java/java-impl/src/com/intellij/psi/impl/PsiSubstitutorImpl.java

@@ -16,7 +16,6 @@
 package com.intellij.psi.impl;
 
 import com.intellij.openapi.diagnostic.Logger;
-import com.intellij.openapi.util.Comparing;
 import com.intellij.psi.*;
 import com.intellij.psi.util.TypeConversionUtil;
 import com.intellij.util.containers.HashMap;
@@ -43,15 +42,7 @@ public class PsiSubstitutorImpl implements PsiSubstitutor {
       return name == null ? 0 : name.hashCode();
     }
     public boolean equals(PsiTypeParameter element1, PsiTypeParameter element2) {
-      if (element1 == element2 || element1.equals(element2)) return true;
-      if (!Comparing.strEqual(element1.getName(), element2.getName())) return false;
-      PsiTypeParameterListOwner owner1 = element1.getOwner();
-      PsiTypeParameterListOwner owner2 = element2.getOwner();
-      boolean b = owner1 instanceof PsiClass && owner2 instanceof PsiClass && element1.getManager().areElementsEquivalent(owner1, owner2);
-      if (b) {
-        return b;
-      }
-      return false;
+      return element1.getManager().areElementsEquivalent(element1, element2);
     }
   };
 
@@ -303,7 +294,8 @@ public class PsiSubstitutorImpl implements PsiSubstitutor {
           if (aClass != null) {
             if (aClass instanceof PsiTypeParameter) {
               return rawTypeForTypeParameter((PsiTypeParameter)aClass);
-            } else {
+            }
+            else {
               return JavaPsiFacade.getInstance(aClass.getProject()).getElementFactory().createType(aClass);
             }
           }

java/openapi/src/com/intellij/psi/util/MethodSignatureUtil.java

@@ -90,7 +90,7 @@ public class MethodSignatureUtil {
     return true;
   }
 
-  private static boolean areSignaturesEqualLightweight(MethodSignature sig1, MethodSignature sig2) {
+  public static boolean areSignaturesEqualLightweight(MethodSignature sig1, MethodSignature sig2) {
     String name1 = sig1.getName();
     String name2 = sig2.getName();
     if (!name1.equals(name2)) return false;