Replace writeSymref with RefUpdate.link

By using RefUpdate for symbolic reference creation we can reuse
the logic related to updating the reflog with the event, without
needing to expose something such as the legacy ReflogWriter class
(which we no longer have).

Applications using writeSymref must update their code to use the
new pattern of changing the reference through the updateRef method:

    String refName = "refs/heads/master";
    RefUpdate u = repository.updateRef(Constants.HEAD);
    u.setRefLogMessage("checkout: moving to " + refName, false);
    switch (u.link(refName)) {
    case NEW:
    case FORCED:
    case NO_CHANGE:
        // A successful update of the reference
        break;
    default:
        // Handle the failure, e.g. for older behavior
        throw new IOException(u.getResult());
    }

Change-Id: I1093e1ec2970147978a786cfdd0a75d0aebf8010
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

2 files changed, 37 insertions, 12 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefTest.java
index 42c8a92b93..100b758e65 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefTest.java
@@ -1,4 +1,5 @@
 /*
+ * Copyright (C) 2009-2010, Google Inc.
  * Copyright (C) 2009, Robin Rosenberg
  * Copyright (C) 2009, Robin Rosenberg <robin.rosenberg@dewire.com>
  * and other copyright owners as documented in the project's IP log.
@@ -58,15 +59,26 @@ import org.eclipse.jgit.lib.RefUpdate.Result;
  */
 public class RefTest extends SampleDataRepositoryTestCase {
 
+	private void writeSymref(String src, String dst) throws IOException {
+		RefUpdate u = db.updateRef(src);
+		switch (u.link(dst)) {
+		case NEW:
+		case FORCED:
+		case NO_CHANGE:
+			break;
+		default:
+			fail("link " + src + " to " + dst);
+		}
+	}
+
 	public void testReadAllIncludingSymrefs() throws Exception {
 		ObjectId masterId = db.resolve("refs/heads/master");
 		RefUpdate updateRef = db.updateRef("refs/remotes/origin/master");
 		updateRef.setNewObjectId(masterId);
 		updateRef.setForceUpdate(true);
 		updateRef.update();
-		db
-				.writeSymref("refs/remotes/origin/HEAD",
-						"refs/remotes/origin/master");
+		writeSymref("refs/remotes/origin/HEAD",
+					"refs/remotes/origin/master");
 
 		ObjectId r = db.resolve("refs/remotes/origin/HEAD");
 		assertEquals(masterId, r);
@@ -85,7 +97,7 @@ public class RefTest extends SampleDataRepositoryTestCase {
 	}
 
 	public void testReadSymRefToPacked() throws IOException {
-		db.writeSymref("HEAD", "refs/heads/b");
+		writeSymref("HEAD", "refs/heads/b");
 		Ref ref = db.getRef("HEAD");
 		assertEquals(Ref.Storage.LOOSE, ref.getStorage());
 		assertTrue("is symref", ref.isSymbolic());
@@ -102,7 +114,7 @@ public class RefTest extends SampleDataRepositoryTestCase {
 		Result update = updateRef.update();
 		assertEquals(Result.FORCED, update); // internal
 
-		db.writeSymref("HEAD", "refs/heads/master");
+		writeSymref("HEAD", "refs/heads/master");
 		Ref ref = db.getRef("HEAD");
 		assertEquals(Ref.Storage.LOOSE, ref.getStorage());
 		ref = ref.getTarget();
diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefUpdateTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefUpdateTest.java
index cb9111758a..c8a5b33f68 100644
--- a/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefUpdateTest.java
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/lib/RefUpdateTest.java
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2008, Charles O'Farrell <charleso@charleso.org>
+ * Copyright (C) 2009-2010, Google Inc.
  * Copyright (C) 2008-2009, Robin Rosenberg <robin.rosenberg@dewire.com>
  * and other copyright owners as documented in the project's IP log.
  *
@@ -56,6 +57,18 @@ import org.eclipse.jgit.revwalk.RevWalk;
 
 public class RefUpdateTest extends SampleDataRepositoryTestCase {
 
+	private void writeSymref(String src, String dst) throws IOException {
+		RefUpdate u = db.updateRef(src);
+		switch (u.link(dst)) {
+		case NEW:
+		case FORCED:
+		case NO_CHANGE:
+			break;
+		default:
+			fail("link " + src + " to " + dst);
+		}
+	}
+
 	private RefUpdate updateRef(final String name) throws IOException {
 		final RefUpdate ref = db.updateRef(name);
 		ref.setNewObjectId(db.resolve(Constants.HEAD));
@@ -328,7 +341,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 	 */
 	public void testUpdateRefDetachedUnbornHead() throws Exception {
 		ObjectId ppid = db.resolve("refs/heads/master^");
-		db.writeSymref("HEAD", "refs/heads/unborn");
+		writeSymref("HEAD", "refs/heads/unborn");
 		RefUpdate updateRef = db.updateRef("HEAD", true);
 		updateRef.setForceUpdate(true);
 		updateRef.setNewObjectId(ppid);
@@ -437,7 +450,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 		// Do not use the defalt repo for this case.
 		Map<String, Ref> allRefs = db.getAllRefs();
 		ObjectId oldValue = db.resolve("HEAD");
-		db.writeSymref(Constants.HEAD, "refs/heads/newref");
+		writeSymref(Constants.HEAD, "refs/heads/newref");
 		RefUpdate updateRef = db.updateRef(Constants.HEAD);
 		updateRef.setForceUpdate(true);
 		updateRef.setNewObjectId(oldValue);
@@ -601,7 +614,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 
 	public void testRenameCurrentBranch() throws IOException {
 		ObjectId rb = db.resolve("refs/heads/b");
-		db.writeSymref(Constants.HEAD, "refs/heads/b");
+		writeSymref(Constants.HEAD, "refs/heads/b");
 		ObjectId oldHead = db.resolve(Constants.HEAD);
 		assertTrue("internal test condition, b == HEAD", rb.equals(oldHead));
 		writeReflog(db, rb, rb, "Just a message", "refs/heads/b");
@@ -659,7 +672,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 	public void tryRenameWhenLocked(String toLock, String fromName,
 			String toName, String headPointsTo) throws IOException {
 		// setup
-		db.writeSymref(Constants.HEAD, headPointsTo);
+		writeSymref(Constants.HEAD, headPointsTo);
 		ObjectId oldfromId = db.resolve(fromName);
 		ObjectId oldHeadId = db.resolve(Constants.HEAD);
 		writeReflog(db, oldfromId, oldfromId, "Just a message",
@@ -753,7 +766,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 	public void testRenameRefNameColission1avoided() throws IOException {
 		// setup
 		ObjectId rb = db.resolve("refs/heads/b");
-		db.writeSymref(Constants.HEAD, "refs/heads/a");
+		writeSymref(Constants.HEAD, "refs/heads/a");
 		RefUpdate updateRef = db.updateRef("refs/heads/a");
 		updateRef.setNewObjectId(rb);
 		updateRef.setRefLogMessage("Setup", false);
@@ -785,7 +798,7 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 	public void testRenameRefNameColission2avoided() throws IOException {
 		// setup
 		ObjectId rb = db.resolve("refs/heads/b");
-		db.writeSymref(Constants.HEAD, "refs/heads/prefix/a");
+		writeSymref(Constants.HEAD, "refs/heads/prefix/a");
 		RefUpdate updateRef = db.updateRef("refs/heads/prefix/a");
 		updateRef.setNewObjectId(rb);
 		updateRef.setRefLogMessage("Setup", false);
@@ -823,6 +836,6 @@ public class RefUpdateTest extends SampleDataRepositoryTestCase {
 		RefDirectoryUpdate update = refs.newUpdate(refName, true);
 		update.setOldObjectId(oldId);
 		update.setNewObjectId(newId);
-		refs.log(update, msg);
+		refs.log(update, msg, true);
 	}
 }