From f4e8b5008069bc246eab22c8a2aa86236f8cb618 Mon Sep 17 00:00:00 2001
From: Kirill Likhodedov <Kirill.Likhodedov@jetbrains.com>
Date: Tue, 30 Apr 2013 14:33:00 +0400
Subject: [PATCH] [git] GitMergeProvider: use Set instead of Map<..., Boolean>

Also solves a potential NPE in checking myReverseMap.get(root).
Relates to the fix for IDEA-78808
---
 .../src/git4idea/merge/GitMergeProvider.java  | 25 +++++++++++--------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/plugins/git4idea/src/git4idea/merge/GitMergeProvider.java b/plugins/git4idea/src/git4idea/merge/GitMergeProvider.java
index 6f8d8953e51d..3e5dcd92cf8b 100644
--- a/plugins/git4idea/src/git4idea/merge/GitMergeProvider.java
+++ b/plugins/git4idea/src/git4idea/merge/GitMergeProvider.java
@@ -47,6 +47,7 @@ import java.io.IOException;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 
 /**
  * Merge-changes provider for Git, used by IDEA internal 3-way merge tool
@@ -63,28 +64,30 @@ public class GitMergeProvider implements MergeProvider2 {
    * If true the merge provider has a reverse meaning, i. e. yours and theirs are swapped.
    * It should be used when conflict is resolved after rebase or unstash.
    */
-  @NotNull private final Map<VirtualFile, Boolean> myReverseMap;
+  @NotNull private final Set<VirtualFile> myReverseRoots;
 
-  private GitMergeProvider(@NotNull Project project, @NotNull Map<VirtualFile, Boolean> reverseMap) {
+  private GitMergeProvider(@NotNull Project project, @NotNull Set<VirtualFile> reverseRoots) {
     myProject = project;
-    myReverseMap = reverseMap;
+    myReverseRoots = reverseRoots;
   }
 
   public GitMergeProvider(@NotNull Project project, boolean reverse) {
-    this(project, buildReverseMap(project, reverse));
+    this(project, findReverseRoots(project, reverse));
   }
 
   @NotNull
   public static MergeProvider detect(@NotNull Project project) {
-    return new GitMergeProvider(project, buildReverseMap(project, null));
+    return new GitMergeProvider(project, findReverseRoots(project, null));
   }
 
   @NotNull
-  private static Map<VirtualFile, Boolean> buildReverseMap(@NotNull Project project, @Nullable Boolean reverseOrDetect) {
-    Map<VirtualFile, Boolean> reverseMap = ContainerUtil.newHashMap();
+  private static Set<VirtualFile> findReverseRoots(@NotNull Project project, @Nullable Boolean reverseOrDetect) {
+    Set<VirtualFile> reverseMap = ContainerUtil.newHashSet();
     for (GitRepository repository : GitUtil.getRepositoryManager(project).getRepositories()) {
       boolean reverse = reverseOrDetect == null ? repository.getState().equals(GitRepository.State.REBASING) : reverseOrDetect;
-      reverseMap.put(repository.getRoot(), reverse);
+      if (reverse) {
+        reverseMap.add(repository.getRoot());
+      }
     }
     return reverseMap;
   }
@@ -126,7 +129,7 @@ public class GitMergeProvider implements MergeProvider2 {
 
   @Nullable
   private VcsRevisionNumber findLastRevisionNumber(@NotNull VirtualFile root) {
-    if (myReverseMap.get(root)) {
+    if (myReverseRoots.contains(root)) {
       return resolveHead(root);
     }
     else {
@@ -179,7 +182,7 @@ public class GitMergeProvider implements MergeProvider2 {
    * @param root
    */
   private int yoursRevision(@NotNull VirtualFile root) {
-    return myReverseMap.get(root) ? THEIRS_REVISION_NUM : YOURS_REVISION_NUM;
+    return myReverseRoots.contains(root) ? THEIRS_REVISION_NUM : YOURS_REVISION_NUM;
   }
 
   /**
@@ -187,7 +190,7 @@ public class GitMergeProvider implements MergeProvider2 {
    * @param root
    */
   private int theirsRevision(@NotNull VirtualFile root) {
-    return myReverseMap.get(root) ? YOURS_REVISION_NUM : THEIRS_REVISION_NUM;
+    return myReverseRoots.contains(root) ? YOURS_REVISION_NUM : THEIRS_REVISION_NUM;
   }
 
   public void conflictResolvedForFile(VirtualFile file) {