Add progress monitor to Merger

Monitoring progress of merges can be useful for users for large
repositories or complex merge processes that take some time.

This enables setting a monitor. Existing merge implementations in jgit
do not yet report progress if a monitor is set. This will be added in a
later change.

Change-Id: I17b978b3fc91750dd88649638b90a46820a0877c
Signed-off-by: Laurent Delaigue <laurent.delaigue@obeo.fr>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit/src/org/eclipse/jgit/api/MergeCommand.java

@@ -1,6 +1,7 @@
 /*
  * Copyright (C) 2010, Christian Halstrick <christian.halstrick@sap.com>
  * Copyright (C) 2010-2014, Stefan Lay <stefan.lay@sap.com>
+ * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
@@ -65,8 +66,10 @@ import org.eclipse.jgit.internal.JGitText;
 import org.eclipse.jgit.lib.AnyObjectId;
 import org.eclipse.jgit.lib.Config.ConfigEnum;
 import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.NullProgressMonitor;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectIdRef;
+import org.eclipse.jgit.lib.ProgressMonitor;
 import org.eclipse.jgit.lib.Ref;
 import org.eclipse.jgit.lib.Ref.Storage;
 import org.eclipse.jgit.lib.RefUpdate;
@@ -106,6 +109,8 @@ public class MergeCommand extends GitCommand<MergeResult> {
 
 	private String message;
 
+	private ProgressMonitor monitor = NullProgressMonitor.INSTANCE;
+
 	/**
 	 * The modes available for fast forward merges corresponding to the
 	 * <code>--ff</code>, <code>--no-ff</code> and <code>--ff-only</code>
@@ -330,6 +335,7 @@ public class MergeCommand extends GitCommand<MergeResult> {
 					repo.writeSquashCommitMsg(squashMessage);
 				}
 				Merger merger = mergeStrategy.newMerger(repo);
+				merger.setProgressMonitor(monitor);
 				boolean noProblems;
 				Map<String, org.eclipse.jgit.merge.MergeResult<?>> lowLevelResults = null;
 				Map<String, MergeFailureReason> failingPaths = null;
@@ -586,4 +592,23 @@ public class MergeCommand extends GitCommand<MergeResult> {
 		this.message = message;
 		return this;
 	}
+
+	/**
+	 * The progress monitor associated with the diff operation. By default, this
+	 * is set to <code>NullProgressMonitor</code>
+	 *
+	 * @see NullProgressMonitor
+	 *
+	 * @param monitor
+	 *            A progress monitor
+	 * @return this instance
+	 * @since 4.2
+	 */
+	public MergeCommand setProgressMonitor(ProgressMonitor monitor) {
+		if (monitor == null) {
+			monitor = NullProgressMonitor.INSTANCE;
+		}
+		this.monitor = monitor;
+		return this;
+	}
 }

org.eclipse.jgit/src/org/eclipse/jgit/api/PullCommand.java

@@ -1,6 +1,7 @@
 /*
  * Copyright (C) 2010, Christian Halstrick <christian.halstrick@sap.com>
  * Copyright (C) 2010, Mathias Kinzler <mathias.kinzler@sap.com>
+ * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
@@ -326,6 +327,7 @@ public class PullCommand extends TransportCommand<PullCommand, PullResult> {
 			MergeCommand merge = new MergeCommand(repo);
 			merge.include(upstreamName, commitToMerge);
 			merge.setStrategy(strategy);
+			merge.setProgressMonitor(monitor);
 			MergeResult mergeRes = merge.call();
 			monitor.update(1);
 			result = new PullResult(fetchRes, remote, mergeRes);

org.eclipse.jgit/src/org/eclipse/jgit/api/RebaseCommand.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2010, 2013 Mathias Kinzler <mathias.kinzler@sap.com>
+ * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
@@ -611,6 +612,7 @@ public class RebaseCommand extends GitCommand<RebaseResult> {
 					// their non-first parents rewritten
 					MergeCommand merge = git.merge()
 							.setFastForward(MergeCommand.FastForwardMode.NO_FF)
+							.setProgressMonitor(monitor)
 							.setCommit(false);
 					for (int i = 1; i < commitToPick.getParentCount(); i++)
 						merge.include(newParents.get(i));

org.eclipse.jgit/src/org/eclipse/jgit/api/SubmoduleUpdateCommand.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2011, GitHub Inc.
+ * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
@@ -178,11 +179,13 @@ public class SubmoduleUpdateCommand extends
 					if (ConfigConstants.CONFIG_KEY_MERGE.equals(update)) {
 						MergeCommand merge = new MergeCommand(submoduleRepo);
 						merge.include(commit);
+						merge.setProgressMonitor(monitor);
 						merge.setStrategy(strategy);
 						merge.call();
 					} else if (ConfigConstants.CONFIG_KEY_REBASE.equals(update)) {
 						RebaseCommand rebase = new RebaseCommand(submoduleRepo);
 						rebase.setUpstream(commit);
+						rebase.setProgressMonitor(monitor);
 						rebase.setStrategy(strategy);
 						rebase.call();
 					} else {

org.eclipse.jgit/src/org/eclipse/jgit/merge/Merger.java

@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2008-2013, Google Inc.
+ * Copyright (C) 2016, Laurent Delaigue <laurent.delaigue@obeo.fr>
  * and other copyright owners as documented in the project's IP log.
  *
  * This program and the accompanying materials are made available
@@ -51,9 +52,11 @@ import org.eclipse.jgit.errors.NoMergeBaseException;
 import org.eclipse.jgit.errors.NoMergeBaseException.MergeBaseFailureReason;
 import org.eclipse.jgit.internal.JGitText;
 import org.eclipse.jgit.lib.AnyObjectId;
+import org.eclipse.jgit.lib.NullProgressMonitor;
 import org.eclipse.jgit.lib.ObjectId;
 import org.eclipse.jgit.lib.ObjectInserter;
 import org.eclipse.jgit.lib.ObjectReader;
+import org.eclipse.jgit.lib.ProgressMonitor;
 import org.eclipse.jgit.lib.Repository;
 import org.eclipse.jgit.revwalk.RevCommit;
 import org.eclipse.jgit.revwalk.RevObject;
@@ -87,6 +90,13 @@ public abstract class Merger {
 	/** The trees matching every entry in {@link #sourceObjects}. */
 	protected RevTree[] sourceTrees;
 
+	/**
+	 * A progress monitor.
+	 *
+	 * @since 4.2
+	 */
+	protected ProgressMonitor monitor = NullProgressMonitor.INSTANCE;
+
 	/**
 	 * Create a new merge instance for a repository.
 	 *
@@ -290,4 +300,20 @@ public abstract class Merger {
 	 * @return resulting tree, if {@link #merge(AnyObjectId[])} returned true.
 	 */
 	public abstract ObjectId getResultTreeId();
+
+	/**
+	 * Set a progress monitor.
+	 *
+	 * @param monitor
+	 *            Monitor to use, can be null to indicate no progress reporting
+	 *            is desired.
+	 * @since 4.2
+	 */
+	public void setProgressMonitor(ProgressMonitor monitor) {
+		if (monitor == null) {
+			this.monitor = NullProgressMonitor.INSTANCE;
+		} else {
+			this.monitor = monitor;
+		}
+	}
 }