Support pull on detached HEAD

Bug: 485396
Change-Id: I82be09385c9b0bcc0054fea5a9cb9d178a41e278
Signed-off-by: Mickael Istria <mistria@redhat.com>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

1 files changed, 52 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandWithRebaseTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandWithRebaseTest.java
index b405f6ad74..6f6b1158eb 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandWithRebaseTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/PullCommandWithRebaseTest.java
@@ -61,6 +61,7 @@ import org.eclipse.jgit.junit.RepositoryTestCase;
 import org.eclipse.jgit.lib.ConfigConstants;
 import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.lib.RepositoryState;
 import org.eclipse.jgit.lib.StoredConfig;
@@ -148,6 +149,57 @@ public class PullCommandWithRebaseTest extends RepositoryTestCase {
 	}
 
 	@Test
+	public void testPullFastForwardDetachedHead() throws Exception {
+		Repository repository = source.getRepository();
+		writeToFile(sourceFile, "2nd commit");
+		source.add().addFilepattern("SomeFile.txt").call();
+		source.commit().setMessage("2nd commit").call();
+
+		try (RevWalk revWalk = new RevWalk(repository)) {
+			// git checkout HEAD^
+			String initialBranch = repository.getBranch();
+			Ref initialRef = repository.findRef(Constants.HEAD);
+			RevCommit initialCommit = revWalk
+					.parseCommit(initialRef.getObjectId());
+			assertEquals("this test need linear history", 1,
+					initialCommit.getParentCount());
+			source.checkout().setName(initialCommit.getParent(0).getName())
+					.call();
+			assertFalse("expected detached HEAD",
+					repository.getFullBranch().startsWith(Constants.R_HEADS));
+
+			// change and commit another file
+			File otherFile = new File(sourceFile.getParentFile(),
+					System.currentTimeMillis() + ".tst");
+			writeToFile(otherFile, "other 2nd commit");
+			source.add().addFilepattern(otherFile.getName()).call();
+			RevCommit newCommit = source.commit().setMessage("other 2nd commit")
+					.call();
+
+			// git pull --rebase initialBranch
+			source.pull().setRebase(true).setRemote(".")
+					.setRemoteBranchName(initialBranch)
+					.call();
+
+			assertEquals(RepositoryState.SAFE,
+					source.getRepository().getRepositoryState());
+			Ref head = source.getRepository().findRef(Constants.HEAD);
+			RevCommit headCommit = revWalk.parseCommit(head.getObjectId());
+
+			// HEAD^ == initialCommit, no merge commit
+			assertEquals(1, headCommit.getParentCount());
+			assertEquals(initialCommit, headCommit.getParent(0));
+
+			// both contributions for both commits are available
+			assertFileContentsEqual(sourceFile, "2nd commit");
+			assertFileContentsEqual(otherFile, "other 2nd commit");
+			// HEAD has same message as rebased commit
+			assertEquals(newCommit.getShortMessage(),
+					headCommit.getShortMessage());
+		}
+	}
+
+	@Test
 	public void testPullConflict() throws Exception {
 		PullResult res = target.pull().call();
 		// nothing to update since we don't have different data yet