Evaluate short refnames into full names during push

With this we can use short names like master instead of refs/heads/master
when pushing. This is slightly more convenient. Pushing a delete still
requires the long format.

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.spearce.jgit/src/org/spearce/jgit/lib/Repository.java

@@ -926,7 +926,21 @@ public String getBranch() throws IOException {
 			return ref;
 		}
 	}
-
+
+	/**
+	 * Get a ref by name.
+	 *
+	 * @param name
+	 *            the name of the ref to lookup. May be a short-hand form, e.g.
+	 *            "master" which is is automatically expanded to
+	 *            "refs/heads/master" if "refs/heads/master" already exists.
+	 * @return the Ref with the given name, or null if it does not exist
+	 * @throws IOException
+	 */
+	public Ref getRef(final String name) throws IOException {
+		return refs.readRef(name);
+	}
+
 	/**
 	 * @return all known refs (heads, tags, remotes).
 	 */

org.spearce.jgit/src/org/spearce/jgit/transport/Transport.java

@@ -51,6 +51,7 @@
 
 import org.spearce.jgit.errors.NotSupportedException;
 import org.spearce.jgit.errors.TransportException;
+import org.spearce.jgit.lib.Constants;
 import org.spearce.jgit.lib.NullProgressMonitor;
 import org.spearce.jgit.lib.ProgressMonitor;
 import org.spearce.jgit.lib.Ref;
@@ -243,10 +244,24 @@ public static Collection<RemoteRefUpdate> findRemoteRefUpdatesFor(
 		final Collection<RefSpec> procRefs = expandPushWildcardsFor(db, specs);
 
 		for (final RefSpec spec : procRefs) {
-			final String srcRef = spec.getSource();
+			String srcRef = spec.getSource();
+			final Ref src = db.getRef(srcRef);
+			if (src != null)
+				srcRef = src.getName();
+			String remoteName = spec.getDestination();
 			// null destination (no-colon in ref-spec) is a special case
-			final String remoteName = (spec.getDestination() == null ? spec
-					.getSource() : spec.getDestination());
+			if (remoteName == null) {
+				remoteName = srcRef;
+			} else {
+				if (!remoteName.startsWith(Constants.R_REFS)) {
+					// null source is another special case (delete)
+					if (srcRef != null) {
+						// assume the same type of ref at the destination
+						String srcPrefix = srcRef.substring(0, srcRef.indexOf('/', Constants.R_REFS.length()));
+						remoteName = srcPrefix + "/" + remoteName;
+					}
+				}
+			}
 			final boolean forceUpdate = spec.isForceUpdate();
 			final String localName = findTrackingRefName(remoteName, fetchSpecs);