Detaching HEAD when checking out the same commit.
Detaching HEAD didn't work in some corner checkout cases. If, for example,
HEAD is symbolic ref to refs/heads/master, refs/heads/master is ref to commit
c0ffee... then:
checkout c0ffee...
would leave the HEAD unchanged.
The same symptom occurs when checking out a remote tracking branch or a tag
that references the same commit as refs/heads/master.
In the above case, the RefUpdate class didn't have enough information to decide
if the update needed to detach symbolic ref because it dealt only with new/old
objectIDs. Therefore, this fix introduced the RefUpdate.detachingSymbolicRef
flag.
Bug: 315166
Change-Id: I085c98b77ea8f9104a213978ea0d4ac6fd58f49b
Signed-off-by: Sasa Zivkov <sasa.zivkov@sap.com>
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CheckoutCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CheckoutCommandTest.java
index 21fbe0a..6e9f851 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CheckoutCommandTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/CheckoutCommandTest.java
@@ -47,6 +47,7 @@
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertSame;
import static org.junit.Assert.assertTrue;
import static org.junit.Assert.fail;
@@ -239,4 +240,20 @@ public void testCheckoutRemoteTrackingWithoutLocalBranch() {
fail(e.getMessage());
}
}
+
+ @Test
+ public void testDetachedHeadOnCheckout() throws JGitInternalException,
+ RefAlreadyExistsException, RefNotFoundException,
+ InvalidRefNameException, IOException {
+ CheckoutCommand co = git.checkout();
+ co.setName("master").call();
+
+ String commitId = db.getRef(Constants.MASTER).getObjectId().name();
+ co = git.checkout();
+ co.setName(commitId).call();
+
+ Ref head = db.getRef(Constants.HEAD);
+ assertFalse(head.isSymbolic());
+ assertSame(head, head.getTarget());
+ }
}
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java b/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
index e6f8933..24af944 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/lib/RefUpdate.java
@@ -168,6 +168,17 @@ public static enum Result {
private final Ref ref;
/**
+ * Is this RefUpdate detaching a symbolic ref?
+ *
+ * We need this info since this.ref will normally be peeled of in case of
+ * detaching a symbolic ref (HEAD for example).
+ *
+ * Without this flag we cannot decide whether the ref has to be updated or
+ * not in case when it was a symbolic ref and the newValue == oldValue.
+ */
+ private boolean detachingSymbolicRef;
+
+ /**
* Construct a new update operation for the reference.
* <p>
* {@code ref.getObjectId()} will be used to seed {@link #getOldObjectId()},
@@ -254,6 +265,13 @@ public ObjectId getNewObjectId() {
}
/**
+ * Tells this RefUpdate that it is actually detaching a symbolic ref.
+ */
+ public void setDetachingSymbolicRef() {
+ detachingSymbolicRef = true;
+ }
+
+ /**
* Set the new value the ref will update to.
*
* @param id
@@ -596,7 +614,7 @@ private Result updateImpl(final RevWalk walk, final Store store)
newObj = safeParse(walk, newValue);
oldObj = safeParse(walk, oldValue);
- if (newObj == oldObj)
+ if (newObj == oldObj && !detachingSymbolicRef)
return store.execute(Result.NO_CHANGE);
if (newObj instanceof RevCommit && oldObj instanceof RevCommit) {
diff --git a/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/RefDirectory.java b/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/RefDirectory.java
index e8ce2c5..c3402df 100644
--- a/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/RefDirectory.java
+++ b/org.eclipse.jgit/src/org/eclipse/jgit/storage/file/RefDirectory.java
@@ -491,15 +491,22 @@ void storedSymbolicRef(RefDirectoryUpdate u, long modified, String target) {
public RefDirectoryUpdate newUpdate(String name, boolean detach)
throws IOException {
+ boolean detachingSymbolicRef = false;
final RefList<Ref> packed = getPackedRefs();
Ref ref = readRef(name, packed);
if (ref != null)
ref = resolve(ref, 0, null, null, packed);
if (ref == null)
ref = new ObjectIdRef.Unpeeled(NEW, name, null);
- else if (detach && ref.isSymbolic())
- ref = new ObjectIdRef.Unpeeled(LOOSE, name, ref.getObjectId());
- return new RefDirectoryUpdate(this, ref);
+ else {
+ detachingSymbolicRef = detach && ref.isSymbolic();
+ if (detachingSymbolicRef)
+ ref = new ObjectIdRef.Unpeeled(LOOSE, name, ref.getObjectId());
+ }
+ RefDirectoryUpdate refDirUpdate = new RefDirectoryUpdate(this, ref);
+ if (detachingSymbolicRef)
+ refDirUpdate.setDetachingSymbolicRef();
+ return refDirUpdate;
}
@Override
