Fix reading of ref names containing characters that sort before /

A set of ref names like ('a/b' and 'a+b') would cause the RefDirectory
to think that the set of refs have changed because it traversed the
'a' directory in the subtree before looking at 'a+b', but it then
compared with the know refs which are sorted with 'a+b' first.

Fix this by traversing the refs tree in another order. Treat a directory
as if they ends with a '/' before deciding on the order to traverse
the refs tree.

Bug: 348834
Change-Id: I23377f8df00c7252bf27dbcfba5da193c5403917
Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>

org.eclipse.jgit.test/tst/org/eclipse/jgit/storage/file/RefDirectoryTest.java

@@ -61,6 +61,9 @@ import java.io.File;
 import java.io.IOException;
 import java.util.Map;
 
+import org.eclipse.jgit.events.ListenerHandle;
+import org.eclipse.jgit.events.RefsChangedEvent;
+import org.eclipse.jgit.events.RefsChangedListener;
 import org.eclipse.jgit.junit.LocalDiskRepositoryTestCase;
 import org.eclipse.jgit.junit.TestRepository;
 import org.eclipse.jgit.lib.AnyObjectId;
@@ -465,6 +468,33 @@ public class RefDirectoryTest extends LocalDiskRepositoryTestCase {
 		assertEquals(B, refs.get("refs/heads/project1-B").getObjectId());
 	}
 
+	@Test
+	public void testGetRefs_LooseSorting_Bug_348834() throws IOException {
+		Map<String, Ref> refs;
+
+		writeLooseRef("refs/heads/my/a+b", A);
+		writeLooseRef("refs/heads/my/a/b/c", B);
+
+		final int[] count = new int[1];
+
+		ListenerHandle listener = Repository.getGlobalListenerList()
+				.addRefsChangedListener(new RefsChangedListener() {
+
+					public void onRefsChanged(RefsChangedEvent event) {
+						count[0]++;
+					}
+				});
+
+		refs = refdir.getRefs(RefDatabase.ALL);
+		refs = refdir.getRefs(RefDatabase.ALL);
+		listener.remove();
+		assertEquals(1, count[0]); // Bug 348834 multiple RefsChangedEvents
+		assertEquals(2, refs.size());
+		assertEquals(A, refs.get("refs/heads/my/a+b").getObjectId());
+		assertEquals(B, refs.get("refs/heads/my/a/b/c").getObjectId());
+
+	}
+
 	@Test
 	public void testGetRefs_TagsOnly_AllPacked() throws IOException {
 		Map<String, Ref> tags;

org.eclipse.jgit/src/org/eclipse/jgit/storage/file/RefDirectory.java

@@ -385,10 +385,17 @@ public class RefDirectory extends RefDatabase {
 			if (entries == null) // not a directory or an I/O error
 				return false;
 			if (0 < entries.length) {
+				for (int i = 0; i < entries.length; ++i) {
+					String e = entries[i];
+					File f = new File(dir, e);
+					if (f.isDirectory())
+						entries[i] += '/';
+				}
 				Arrays.sort(entries);
 				for (String name : entries) {
-					File e = new File(dir, name);
-					if (!scanTree(prefix + name + '/', e))
+					if (name.charAt(name.length() - 1) == '/')
+						scanTree(prefix + name, new File(dir, name));
+					else
 						scanOne(prefix + name);
 				}
 			}