[EGIT PATCH 4/7 v3] Handle peeling of loose refs.

[Robin Rosenberg <robin.rosenberg@dewire.com>]

For packed refs we got peeling automatically from packed-refs,
but for loose tags we have to follow the tags and get the leaf
object in order to comply with the documentation.

Signed-off-by: Robin Rosenberg <robin.rosenberg@dewire.com>
---
 org.spearce.jgit/src/org/spearce/jgit/lib/Ref.java |   35 ++++++++++++++-----
 .../src/org/spearce/jgit/lib/RefDatabase.java      |   32 ++++++++++++++++--
 .../src/org/spearce/jgit/lib/Repository.java       |   13 +++++++
 .../spearce/jgit/transport/BasePackConnection.java |    2 +-
 .../spearce/jgit/transport/TransportAmazonS3.java  |    2 +-
 .../org/spearce/jgit/transport/TransportHttp.java  |    2 +-
 .../org/spearce/jgit/transport/TransportSftp.java  |    2 +-
 .../jgit/transport/WalkRemoteObjectDatabase.java   |    2 +-
 8 files changed, 73 insertions(+), 17 deletions(-)

diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/Ref.java b/org.spearce.jgit/src/org/spearce/jgit/lib/Ref.java
index 2f102af..0e98f46 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/Ref.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/Ref.java
@@ -126,6 +126,8 @@ public boolean isPacked() {
 
 	private final String origName;
 
+	private final boolean peeled;
+
 	/**
 	 * Create a new ref pairing.
 	 * 
@@ -140,10 +142,7 @@ public boolean isPacked() {
 	 *            does not exist yet.
 	 */
 	public Ref(final Storage st, final String origName, final String refName, final ObjectId id) {
-		storage = st;
-		this.origName = origName;
-		name = refName;
-		objectId = id;
+		this(st, origName, refName, id, null, false);
 	}
 
 	/**
@@ -158,7 +157,7 @@ public Ref(final Storage st, final String origName, final String refName, final 
 	 *            does not exist yet.
 	 */
 	public Ref(final Storage st, final String refName, final ObjectId id) {
-		this(st, refName, refName, id);
+		this(st, refName, refName, id, null, false);
 	}
 
 	/**
@@ -175,15 +174,18 @@ public Ref(final Storage st, final String refName, final ObjectId id) {
 	 *            does not exist yet.
 	 * @param peel
 	 *            peeled value of the ref's tag. May be null if this is not a
-	 *            tag or the peeled value is not known.
+	 *            tag or not yet peeled (in which case the next parameter should be null)
+	 * @param peeled
+	 * 			  true if peel represents a the peeled value of the object
 	 */
 	public Ref(final Storage st, final String origName, final String refName, final ObjectId id,
-			final ObjectId peel) {
+			final ObjectId peel, final boolean peeled) {
 		storage = st;
 		this.origName = origName;
 		name = refName;
 		objectId = id;
 		peeledObjectId = peel;
+		this.peeled = peeled;
 	}
 
 	/**
@@ -199,10 +201,12 @@ public Ref(final Storage st, final String origName, final String refName, final 
 	 * @param peel
 	 *            peeled value of the ref's tag. May be null if this is not a
 	 *            tag or the peeled value is not known.
+	 * @param peeled
+	 * 			  true if peel represents a the peeled value of the object
 	 */
 	public Ref(final Storage st, final String refName, final ObjectId id,
-			final ObjectId peel) {
-		this(st, refName, refName, id, peel);
+			final ObjectId peel, boolean peeled) {
+		this(st, refName, refName, id, peel, peeled);
 	}
 
 	/**
@@ -238,10 +242,19 @@ public ObjectId getObjectId() {
 	 *         refer to an annotated tag.
 	 */
 	public ObjectId getPeeledObjectId() {
+		if (!peeled)
+			return null;
 		return peeledObjectId;
 	}
 
 	/**
+	 * @return whether the Ref represents a peeled tag
+	 */
+	public boolean isPeeled() {
+		return peeled;
+	}
+
+	/**
 	 * How was this ref obtained?
 	 * <p>
 	 * The current storage model of a Ref may influence how the ref must be
@@ -259,4 +272,8 @@ public String toString() {
 			o = "(" + origName + ")";
 		return "Ref[" + o + name + "=" + ObjectId.toString(getObjectId()) + "]";
 	}
+
+	void setPeeledObjectId(final ObjectId id) {
+		peeledObjectId = id;
+	}
 }
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
index 5a1b85f..494aecb 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/RefDatabase.java
@@ -271,7 +271,8 @@ private void readOneLooseRef(final Map<String, Ref> avail,
 					return;
 				}
 
-				ref = new Ref(Ref.Storage.LOOSE, origName, refName, id);
+				ref = new Ref(Ref.Storage.LOOSE, origName, refName, id, null, false); // unpeeled
+
 				looseRefs.put(ref.getName(), ref);
 				looseRefsMTime.put(ref.getName(), ent.lastModified());
 				avail.put(ref.getName(), ref);
@@ -288,6 +289,28 @@ private void readOneLooseRef(final Map<String, Ref> avail,
 		}
 	}
 
+	Ref peel(final Ref ref) {
+		if (ref.isPeeled())
+			return ref;
+		ObjectId peeled = null;
+		try {
+			Object target = db.mapObject(ref.getObjectId(), ref.getName());
+			while (target instanceof Tag) {
+				final Tag tag = (Tag)target;
+				peeled = tag.getObjId();
+				if (Constants.TYPE_TAG.equals(tag.getType()))
+					target = db.mapObject(tag.getObjId(), ref.getName());
+				else
+					break;
+			}
+		} catch (IOException e) {
+			// Ignore a read error.  Callers will also get the same error
+			// if they try to use the result of getPeeledObjectId.
+		}
+		return new Ref(ref.getStorage(), ref.getName(), ref.getObjectId(), peeled, true);
+
+	}
+
 	private File fileForRef(final String name) {
 		if (name.startsWith(REFS_SLASH))
 			return new File(refsDir, name.substring(REFS_SLASH.length()));
@@ -350,7 +373,7 @@ private Ref readRefBasic(final String origName, final String name, final int dep
 			if (r == null)
 				return new Ref(Ref.Storage.LOOSE, origName, target, null);
 			if (!origName.equals(r.getName()))
-				r = new Ref(Ref.Storage.LOOSE_PACKED, origName, r.getName(), r.getObjectId(), r.getPeeledObjectId());
+				r = new Ref(Ref.Storage.LOOSE_PACKED, origName, r.getName(), r.getObjectId(), r.getPeeledObjectId(), true);
 			return r; 
 		}
 
@@ -364,6 +387,9 @@ private Ref readRefBasic(final String origName, final String name, final int dep
 		}
 
 		ref = new Ref(Ref.Storage.LOOSE, origName, name, id);
+
+		looseRefs.put(origName, ref);
+		ref = new Ref(Ref.Storage.LOOSE, origName, id);
 		looseRefs.put(name, ref);
 		looseRefsMTime.put(name, mtime);
 		return ref;
@@ -397,7 +423,7 @@ private void refreshPackedRefs() {
 
 						final ObjectId id = ObjectId.fromString(p.substring(1));
 						last = new Ref(Ref.Storage.PACKED, last.getName(), last
-								.getName(), last.getObjectId(), id);
+								.getName(), last.getObjectId(), id, true);
 						newPackedRefs.put(last.getName(), last);
 						continue;
 					}
diff --git a/org.spearce.jgit/src/org/spearce/jgit/lib/Repository.java b/org.spearce.jgit/src/org/spearce/jgit/lib/Repository.java
index 26748e2..4d6e6fd 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/lib/Repository.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/lib/Repository.java
@@ -939,6 +939,19 @@ public String getBranch() throws IOException {
 	}
 
 	/**
+	 * Peel a possibly unpeeled ref and updates it. If the ref cannot be peeled
+	 * the peeled id is set to {@link ObjectId#zeroId()}
+	 * 
+	 * @param ref
+	 *            The ref to peel
+	 * @return The same, an updated ref with peeled info or a new instance with
+	 *         more information
+	 */
+	public Ref peel(final Ref ref) {
+		return refs.peel(ref);
+	}
+
+	/**
 	 * @return true if HEAD points to a StGit patch.
 	 */
 	public boolean isStGitMode() {
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/BasePackConnection.java b/org.spearce.jgit/src/org/spearce/jgit/transport/BasePackConnection.java
index e5fc040..e9df30e 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/BasePackConnection.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/BasePackConnection.java
@@ -176,7 +176,7 @@ private void readAdvertisedRefsImpl() throws IOException {
 					throw duplicateAdvertisement(name + "^{}");
 
 				avail.put(name, new Ref(Ref.Storage.NETWORK, name, prior
-						.getObjectId(), id));
+						.getObjectId(), id, true));
 			} else {
 				final Ref prior;
 				prior = avail.put(name, new Ref(Ref.Storage.NETWORK, name, id));
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportAmazonS3.java b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportAmazonS3.java
index f9df36d..9f1b516 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportAmazonS3.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportAmazonS3.java
@@ -300,7 +300,7 @@ private Ref readRef(final TreeMap<String, Ref> avail, final String rn)
 				if (r == null)
 					return null;
 				r = new Ref(r.getStorage(), rn, r.getObjectId(), r
-						.getPeeledObjectId());
+						.getPeeledObjectId(), r.isPeeled());
 				avail.put(r.getName(), r);
 				return r;
 			}
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportHttp.java b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportHttp.java
index 1357e58..fe4a437 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportHttp.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportHttp.java
@@ -237,7 +237,7 @@ FileStream open(final String path) throws IOException {
 						throw duplicateAdvertisement(name + "^{}");
 
 					avail.put(name, new Ref(Ref.Storage.NETWORK, name, prior
-							.getObjectId(), id));
+							.getObjectId(), id, true));
 				} else {
 					final Ref prior = avail.put(name, new Ref(
 							Ref.Storage.NETWORK, name, id));
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportSftp.java b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportSftp.java
index 78f4ad8..544e77c 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/TransportSftp.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/TransportSftp.java
@@ -428,7 +428,7 @@ private Ref readRef(final TreeMap<String, Ref> avail,
 					r = avail.get(p);
 				if (r != null) {
 					r = new Ref(loose(r), name, r.getObjectId(), r
-							.getPeeledObjectId());
+							.getPeeledObjectId(), true);
 					avail.put(name, r);
 				}
 				return r;
diff --git a/org.spearce.jgit/src/org/spearce/jgit/transport/WalkRemoteObjectDatabase.java b/org.spearce.jgit/src/org/spearce/jgit/transport/WalkRemoteObjectDatabase.java
index 54dd581..a4f8961 100644
--- a/org.spearce.jgit/src/org/spearce/jgit/transport/WalkRemoteObjectDatabase.java
+++ b/org.spearce.jgit/src/org/spearce/jgit/transport/WalkRemoteObjectDatabase.java
@@ -438,7 +438,7 @@ private void readPackedRefsImpl(final Map<String, Ref> avail,
 					throw new TransportException("Peeled line before ref.");
 				final ObjectId id = ObjectId.fromString(line + 1);
 				last = new Ref(Ref.Storage.PACKED, last.getName(), last
-						.getObjectId(), id);
+						.getObjectId(), id, true);
 				avail.put(last.getName(), last);
 				continue;
 			}
-- 
1.6.0.3.640.g6331a.dirty