Make recursive merge strategy the default merge strategy

Use recursive merge as the default strategy since it can successfully
merge more cases than the resolve strategy can. This is also the default
in native Git.

Change-Id: I38fd522edb2791f15d83e99038185edb09fed8e1
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.pgm.test/tst/org/eclipse/jgit/pgm/MergeTest.java

@@ -97,7 +97,7 @@ public class MergeTest extends CLIRepositoryTestCase {
 		git.add().addFilepattern("side").call();
 		git.commit().setMessage("side commit").call();
 
-		assertEquals("Merge made by the '" + MergeStrategy.RESOLVE.getName()
+		assertEquals("Merge made by the '" + MergeStrategy.RECURSIVE.getName()
 				+ "' strategy.", execute("git merge master")[0]);
 	}
 

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/Merge.java

@@ -75,7 +75,7 @@ class Merge extends TextBuiltin {
 	@Option(name = "--no-commit", usage = "usage_noCommit")
 	private boolean noCommit = false;
 
-	private MergeStrategy mergeStrategy = MergeStrategy.RESOLVE;
+	private MergeStrategy mergeStrategy = MergeStrategy.RECURSIVE;
 
 	@Argument(required = true)
 	private String ref;

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

@@ -150,7 +150,7 @@ public class CherryPickCommand extends GitCommand<CherryPickResult> {
 				String cherryPickName = srcCommit.getId().abbreviate(7).name()
 						+ " " + srcCommit.getShortMessage(); //$NON-NLS-1$
 
-				ResolveMerger merger = (ResolveMerger) MergeStrategy.RESOLVE
+				ResolveMerger merger = (ResolveMerger) MergeStrategy.RECURSIVE
 						.newMerger(repo);
 				merger.setWorkingTreeIterator(new FileTreeIterator(repo));
 				merger.setBase(srcParent.getTree());

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

@@ -95,7 +95,7 @@ import org.eclipse.jgit.util.StringUtils;
  */
 public class MergeCommand extends GitCommand<MergeResult> {
 
-	private MergeStrategy mergeStrategy = MergeStrategy.RESOLVE;
+	private MergeStrategy mergeStrategy = MergeStrategy.RECURSIVE;
 
 	private List<Ref> commits = new LinkedList<Ref>();
 

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

@@ -160,7 +160,7 @@ public class RevertCommand extends GitCommand<RevCommit> {
 				String revertName = srcCommit.getId().abbreviate(7).name()
 						+ " " + srcCommit.getShortMessage(); //$NON-NLS-1$
 
-				ResolveMerger merger = (ResolveMerger) MergeStrategy.RESOLVE
+				ResolveMerger merger = (ResolveMerger) MergeStrategy.RECURSIVE
 						.newMerger(repo);
 				merger.setWorkingTreeIterator(new FileTreeIterator(repo));
 				merger.setBase(srcCommit.getTree());
@@ -194,14 +194,15 @@ public class RevertCommand extends GitCommand<RevCommit> {
 								merger.getBaseCommit(0, 1),
 								new ObjectId[] { headCommit.getId(),
 										srcParent.getId() },
-								MergeStatus.FAILED, MergeStrategy.RESOLVE,
+								MergeStatus.FAILED, MergeStrategy.RECURSIVE,
 								merger.getMergeResults(), failingPaths, null);
 					else
 						failingResult = new MergeResult(null,
 								merger.getBaseCommit(0, 1),
 								new ObjectId[] { headCommit.getId(),
 										srcParent.getId() },
-								MergeStatus.CONFLICTING, MergeStrategy.RESOLVE,
+								MergeStatus.CONFLICTING,
+								MergeStrategy.RECURSIVE,
 								merger.getMergeResults(), failingPaths, null);
 					if (!merger.failed() && !unmergedPaths.isEmpty()) {
 						String message = new MergeMessageFormatter()

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

@@ -168,7 +168,7 @@ public class StashApplyCommand extends GitCommand<ObjectId> {
 					.getParent(1));
 			ObjectId stashHeadCommit = stashCommit.getParent(0);
 
-			ResolveMerger merger = (ResolveMerger) MergeStrategy.RESOLVE
+			ResolveMerger merger = (ResolveMerger) MergeStrategy.RECURSIVE
 					.newMerger(repo);
 			merger.setCommitNames(new String[] { "stashed HEAD", "HEAD",
 					"stash" });
@@ -181,7 +181,7 @@ public class StashApplyCommand extends GitCommand<ObjectId> {
 				dco.setFailOnConflict(true);
 				dco.checkout(); // Ignoring failed deletes....
 				if (applyIndex) {
-					ResolveMerger ixMerger = (ResolveMerger) MergeStrategy.RESOLVE
+					ResolveMerger ixMerger = (ResolveMerger) MergeStrategy.RECURSIVE
 							.newMerger(repo, true);
 					ixMerger.setCommitNames(new String[] { "stashed HEAD",
 							"HEAD", "stashed index" });