Add debugging toString() method to ObjectToPack

Its useful to know what the flags are or what the base that was
selected is.  Dump these out as part of the object's toString.

Change-Id: I8810067fb8337b08b4fcafd5f9ea3e1e31ca6726
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>

org.eclipse.jgit/src/org/eclipse/jgit/storage/pack/ObjectToPack.java

@@ -45,6 +45,7 @@
 package org.eclipse.jgit.storage.pack;
 
 import org.eclipse.jgit.lib.AnyObjectId;
+import org.eclipse.jgit.lib.Constants;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.revwalk.RevObject;
 import org.eclipse.jgit.transport.PackedObjectInfo;
@@ -261,4 +262,31 @@ public class ObjectToPack extends PackedObjectInfo {
 	public void select(StoredObjectRepresentation ref) {
 		// Empty by default.
 	}
+
+	@Override
+	public String toString() {
+		StringBuilder buf = new StringBuilder();
+		buf.append("ObjectToPack[");
+		buf.append(Constants.typeString(getType()));
+		buf.append(" ");
+		buf.append(name());
+		if (wantWrite())
+			buf.append(" wantWrite");
+		if (isReuseAsIs())
+			buf.append(" reuseAsIs");
+		if (isDoNotDelta())
+			buf.append(" doNotDelta");
+		if (getDeltaDepth() > 0)
+			buf.append(" depth=" + getDeltaDepth());
+		if (isDeltaRepresentation()) {
+			if (getDeltaBase() != null)
+				buf.append(" base=inpack:" + getDeltaBase().name());
+			else
+				buf.append(" base=edge:" + getDeltaBaseId().name());
+		}
+		if (isWritten())
+			buf.append(" offset=" + getOffset());
+		buf.append("]");
+		return buf.toString();
+	}
 }