From 953c6249c4fe128346ce77ea7d958b3963f16063 Mon Sep 17 00:00:00 2001
From: Anna Kozlova <anna.kozlova@jetbrains.com>
Date: Tue, 1 Mar 2016 16:42:32 +0100
Subject: [PATCH] safe delete: search for conflicts in usages (IDEA-152126)

---
 .../safeDelete/JavaSafeDeleteProcessor.java   | 21 +++++++++++++++++++
 .../safeDelete/SafeDeleteProcessor.java       |  5 +++--
 .../SafeDeleteProcessorDelegateBase.java      |  4 ++++
 3 files changed, 28 insertions(+), 2 deletions(-)

diff --git a/java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java b/java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java
index b7bd9384442a..1dcf6ba48d2d 100644
--- a/java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java
+++ b/java/java-impl/src/com/intellij/refactoring/safeDelete/JavaSafeDeleteProcessor.java
@@ -256,6 +256,27 @@ public class JavaSafeDeleteProcessor extends SafeDeleteProcessorDelegateBase {
     return null;
   }
 
+  @Override
+  public Collection<String> findConflicts(PsiElement element, PsiElement[] elements, UsageInfo[] usages) {
+    String methodRefFound = null;
+    if (!ApplicationManager.getApplication().isUnitTestMode() && (element instanceof PsiMethod || element instanceof PsiParameter)) {
+      for (UsageInfo usage : usages) {
+        final PsiElement refElement = usage.getElement();
+        if (refElement instanceof PsiMethodReferenceExpression) {
+          methodRefFound = RefactoringBundle.message("expand.method.reference.warning");
+          break;
+        }
+      }
+    }
+    if (methodRefFound != null) {
+      Collection<String> result = new ArrayList<>();
+      result.add(methodRefFound);
+      result.addAll(super.findConflicts(element, elements, usages));
+      return result;
+    }
+    return super.findConflicts(element, elements, usages);
+  }
+
   public Collection<String> findConflicts(@NotNull final PsiElement element, @NotNull final PsiElement[] allElementsToDelete) {
     if (element instanceof PsiMethod) {
       final PsiClass containingClass = ((PsiMethod)element).getContainingClass();
diff --git a/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessor.java b/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessor.java
index 4bb3de24b553..9470cd71c0a3 100644
--- a/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessor.java
+++ b/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessor.java
@@ -26,7 +26,6 @@ import com.intellij.openapi.extensions.Extensions;
 import com.intellij.openapi.project.DumbModePermission;
 import com.intellij.openapi.project.DumbService;
 import com.intellij.openapi.project.Project;
-import com.intellij.openapi.project.ProjectManager;
 import com.intellij.openapi.util.Condition;
 import com.intellij.openapi.util.Ref;
 import com.intellij.psi.*;
@@ -188,7 +187,9 @@ public class SafeDeleteProcessor extends BaseRefactoringProcessor {
     for (PsiElement element : myElements) {
       for(SafeDeleteProcessorDelegate delegate: Extensions.getExtensions(SafeDeleteProcessorDelegate.EP_NAME)) {
         if (delegate.handlesElement(element)) {
-          Collection<String> foundConflicts = delegate.findConflicts(element, myElements);
+          Collection<String> foundConflicts = delegate instanceof SafeDeleteProcessorDelegateBase 
+                                              ? ((SafeDeleteProcessorDelegateBase)delegate).findConflicts(element, myElements, usages)
+                                              : delegate.findConflicts(element, myElements);
           if (foundConflicts != null) {
             conflicts.addAll(foundConflicts);
           }
diff --git a/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessorDelegateBase.java b/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessorDelegateBase.java
index f50343dda6c6..d67692b2f10a 100644
--- a/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessorDelegateBase.java
+++ b/platform/lang-impl/src/com/intellij/refactoring/safeDelete/SafeDeleteProcessorDelegateBase.java
@@ -42,4 +42,8 @@ public abstract class SafeDeleteProcessorDelegateBase implements SafeDeleteProce
   public UsageView showUsages(UsageInfo[] usages, UsageViewPresentation presentation, UsageViewManager manager, PsiElement[] elements) {
     return null;
   }
+
+  public Collection<String> findConflicts(PsiElement element, PsiElement[] elements, UsageInfo[] usages) {
+    return findConflicts(element, elements);
+  }
 }