diff --git a/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryImpl.java b/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryImpl.java
index 02b53b1297ff..0220cb9e8168 100644
--- a/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryImpl.java
+++ b/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryImpl.java
@@ -26,8 +26,8 @@ import org.jetbrains.annotations.NotNull;
 import org.zmlx.hg4idea.HgVcs;
 import org.zmlx.hg4idea.util.HgUtil;
 
+import java.util.Collection;
 import java.util.Collections;
-import java.util.List;
 
 
 /**
@@ -40,7 +40,7 @@ public class HgRepositoryImpl extends RepositoryImpl implements HgRepository {
   @NotNull private final VirtualFile myHgDir;
 
   @NotNull private volatile String myCurrentBranch = DEFAULT_BRANCH;
-  @NotNull private volatile List<String> myBranches = Collections.emptyList();
+  @NotNull private volatile Collection<String> myBranches = Collections.emptySet();
   private boolean myIsFresh = true;
 
 
@@ -84,7 +84,7 @@ public class HgRepositoryImpl extends RepositoryImpl implements HgRepository {
 
   @Override
   @NotNull
-  public List<String> getBranches() {
+  public Collection<String> getBranches() {
     return myBranches;
   }
 
diff --git a/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryReader.java b/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryReader.java
index 0ee66e2ec7c3..0659e39514c3 100644
--- a/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryReader.java
+++ b/plugins/hg4idea/src/org/zmlx/hg4idea/repo/HgRepositoryReader.java
@@ -22,8 +22,9 @@ import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
-import java.util.ArrayList;
-import java.util.List;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -77,8 +78,8 @@ public class HgRepositoryReader {
   }
 
   @NotNull
-  public List<String> readBranches() {
-    List<String> branches = new ArrayList<String>();
+  public Collection<String> readBranches() {
+    Set<String> branches = new HashSet<String>();
     if (!checkIsFresh()) {
       String[] branchesWithHeads = RepositoryUtil.tryLoadFile(myBranchHeadsFile).split("\n");
       // first one - is a head revision: head hash + head number;