Update reflog like C Git during rebase (non-interactive)

Bug: 346350
Change-Id: I119766a00bc52a810c51cffaa19207cb8555ca22
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

2 files changed, 40 insertions, 13 deletions

diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/CherryPickCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/CherryPickCommand.java
index 2ebff14f9c..1b8441170c 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/CherryPickCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/CherryPickCommand.java
@@ -82,6 +82,8 @@ import org.eclipse.jgit.treewalk.FileTreeIterator;
  *      >Git documentation about cherry-pick</a>
  */
 public class CherryPickCommand extends GitCommand<CherryPickResult> {
+	private String reflogPrefix = "cherry-pick:"; //$NON-NLS-1$
+
 	private List<Ref> commits = new LinkedList<Ref>();
 
 	private String ourCommitName = null;
@@ -166,9 +168,8 @@ public class CherryPickCommand extends GitCommand<CherryPickResult> {
 					dco.checkout();
 					newHead = new Git(getRepository()).commit()
 							.setMessage(srcCommit.getFullMessage())
-							.setReflogComment(
-									"cherry-pick: " //$NON-NLS-1$
-											+ srcCommit.getShortMessage())
+							.setReflogComment(reflogPrefix + " " //$NON-NLS-1$
+									+ srcCommit.getShortMessage())
 							.setAuthor(srcCommit.getAuthorIdent()).call();
 					cherryPickedRefs.add(src);
 				} else {
@@ -242,6 +243,21 @@ public class CherryPickCommand extends GitCommand<CherryPickResult> {
 		return this;
 	}
 
+	/**
+	 * Set the prefix to use in the reflog.
+	 * <p>
+	 * This is primarily needed for implementing rebase in terms of
+	 * cherry-picking
+	 *
+	 * @param prefix
+	 *            including ":"
+	 * @return {@code this}
+	 */
+	public CherryPickCommand setReflogPrefix(final String prefix) {
+		this.reflogPrefix = prefix;
+		return this;
+	}
+
 	private String calculateOurName(Ref headRef) {
 		if (ourCommitName != null)
 			return ourCommitName;
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java b/org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java
index 911a4e6294..592a012870 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java
@@ -319,7 +319,8 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 						String ourCommitName = getOurCommitName();
 						CherryPickResult cherryPickResult = new Git(repo)
 								.cherryPick().include(commitToPick)
-								.setOurCommitName(ourCommitName).call();
+								.setOurCommitName(ourCommitName)
+								.setReflogPrefix("rebase:").call(); //$NON-NLS-1$
 						switch (cherryPickResult.getStatus()) {
 						case FAILED:
 							if (operation == Operation.BEGIN)
@@ -353,7 +354,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 			}
 			if (newHead != null) {
 				String headName = rebaseState.readFile(HEAD_NAME);
-				updateHead(headName, newHead);
+				updateHead(headName, newHead, upstreamCommit);
 				FileUtils.delete(rebaseState.getDir(), FileUtils.RECURSIVE);
 				if (lastStepWasForward)
 					return RebaseResult.FAST_FORWARD_RESULT;
@@ -370,18 +371,20 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 	private String getOurCommitName() {
 		// If onto is different from upstream, this should say "onto", but
 		// RebaseCommand doesn't support a different "onto" at the moment.
-		String ourCommitName = "Upstream, based on "
+		String ourCommitName = "Upstream, based on " //$NON-NLS-1$
 				+ Repository.shortenRefName(upstreamCommitName);
 		return ourCommitName;
 	}
 
-	private void updateHead(String headName, RevCommit newHead)
+	private void updateHead(String headName, RevCommit newHead, RevCommit onto)
 			throws IOException {
 		// point the previous head (if any) to the new commit
 
 		if (headName.startsWith(Constants.R_REFS)) {
 			RefUpdate rup = repo.updateRef(headName);
 			rup.setNewObjectId(newHead);
+			rup.setRefLogMessage("rebase finished: " + headName + " onto " //$NON-NLS-1$
+					+ onto.getName(), false);
 			Result res = rup.forceUpdate();
 			switch (res) {
 			case FAST_FORWARD:
@@ -392,6 +395,8 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 				throw new JGitInternalException("Updating HEAD failed");
 			}
 			rup = repo.updateRef(Constants.HEAD);
+			rup.setRefLogMessage("rebase finished: returning to " + headName, //$NON-NLS-1$
+					false);
 			res = rup.link(headName);
 			switch (res) {
 			case FAST_FORWARD:
@@ -614,7 +619,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 		if (head.isSymbolic())
 			headName = head.getTarget().getName();
 		else
-			headName = "detached HEAD";
+			headName = head.getObjectId().getName();
 		ObjectId headId = head.getObjectId();
 		if (headId == null)
 			throw new RefNotFoundException(MessageFormat.format(
@@ -629,10 +634,10 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 			monitor.beginTask(MessageFormat.format(
 					JGitText.get().resettingHead,
 					upstreamCommit.getShortMessage()), ProgressMonitor.UNKNOWN);
-			checkoutCommit(upstreamCommit);
+			checkoutCommit(headName, upstreamCommit);
 			monitor.endTask();
 
-			updateHead(headName, upstreamCommit);
+			updateHead(headName, upstreamCommit, upstream);
 			return RebaseResult.FAST_FORWARD_RESULT;
 		}
 
@@ -691,7 +696,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 				upstreamCommit.getShortMessage()), ProgressMonitor.UNKNOWN);
 		boolean checkoutOk = false;
 		try {
-			checkoutOk = checkoutCommit(upstreamCommit);
+			checkoutOk = checkoutCommit(headName, upstreamCommit);
 		} finally {
 			if (!checkoutOk)
 				FileUtils.delete(rebaseState.getDir(), FileUtils.RECURSIVE);
@@ -732,7 +737,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 		if (head.isSymbolic())
 			headName = head.getTarget().getName();
 		else
-			headName = "detached HEAD";
+			headName = head.getObjectId().getName();
 		return tryFastForward(headName, headCommit, newCommit);
 	}
 
@@ -843,6 +848,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 
 				// update the HEAD
 				RefUpdate refUpdate = repo.updateRef(Constants.HEAD, false);
+				refUpdate.setRefLogMessage("rebase: aborting", false); //$NON-NLS-1$
 				Result res = refUpdate.link(headName);
 				switch (res) {
 				case FAST_FORWARD:
@@ -864,7 +870,8 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 		}
 	}
 
-	private boolean checkoutCommit(RevCommit commit) throws IOException,
+	private boolean checkoutCommit(String headName, RevCommit commit)
+			throws IOException,
 			CheckoutConflictException {
 		try {
 			RevCommit head = walk.parseCommit(repo.resolve(Constants.HEAD));
@@ -880,6 +887,10 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 			RefUpdate refUpdate = repo.updateRef(Constants.HEAD, true);
 			refUpdate.setExpectedOldObjectId(head);
 			refUpdate.setNewObjectId(commit);
+			refUpdate.setRefLogMessage(
+					"checkout: moving from " //$NON-NLS-1$
+							+ Repository.shortenRefName(headName)
+							+ " to " + commit.getName(), false); //$NON-NLS-1$
 			Result res = refUpdate.forceUpdate();
 			switch (res) {
 			case FAST_FORWARD: