Initial implementation of a Rebase command

This is a first iteration to implement Rebase. At the moment, this
does not implement --continue and --skip, so if the first
conflict is found, the only option is to --abort the command.

Bug: 328217
Change-Id: I24d60c0214e71e5572955f8261e10a42e9e95298
Signed-off-by: Mathias Kinzler <mathias.kinzler@sap.com>
Signed-off-by: Chris Aniszczyk <caniszczyk@gmail.com>

1 files changed, 265 insertions, 0 deletions

diff --git a/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java
new file mode 100644
index 0000000000..aee2cc4d84
--- /dev/null
+++ b/org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RebaseCommandTest.java
@@ -0,0 +1,265 @@
+/*
+ * Copyright (C) 2010, Mathias Kinzler <mathias.kinzler@sap.com>
+ * and other copyright owners as documented in the project's IP log.
+ *
+ * This program and the accompanying materials are made available
+ * under the terms of the Eclipse Distribution License v1.0 which
+ * accompanies this distribution, is reproduced below, and is
+ * available at http://www.eclipse.org/org/documents/edl-v10.php
+ *
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or
+ * without modification, are permitted provided that the following
+ * conditions are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ *
+ * - Redistributions in binary form must reproduce the above
+ *   copyright notice, this list of conditions and the following
+ *   disclaimer in the documentation and/or other materials provided
+ *   with the distribution.
+ *
+ * - Neither the name of the Eclipse Foundation, Inc. nor the
+ *   names of its contributors may be used to endorse or promote
+ *   products derived from this software without specific prior
+ *   written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
+ * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
+ * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+ * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+ * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+package org.eclipse.jgit.api;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+import org.eclipse.jgit.api.RebaseCommand.Operation;
+import org.eclipse.jgit.api.RebaseResult.Status;
+import org.eclipse.jgit.dircache.DirCacheCheckout;
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.RefUpdate;
+import org.eclipse.jgit.lib.RepositoryState;
+import org.eclipse.jgit.lib.RepositoryTestCase;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevWalk;
+
+public class RebaseCommandTest extends RepositoryTestCase {
+	private void createBranch(ObjectId objectId, String branchName)
+			throws IOException {
+		RefUpdate updateRef = db.updateRef(branchName);
+		updateRef.setNewObjectId(objectId);
+		updateRef.update();
+	}
+
+	private void checkoutBranch(String branchName)
+			throws IllegalStateException, IOException {
+		RevWalk walk = new RevWalk(db);
+		RevCommit head = walk.parseCommit(db.resolve(Constants.HEAD));
+		RevCommit branch = walk.parseCommit(db.resolve(branchName));
+		DirCacheCheckout dco = new DirCacheCheckout(db, head.getTree().getId(),
+				db.lockDirCache(), branch.getTree().getId());
+		dco.setFailOnConflict(true);
+		dco.checkout();
+		walk.release();
+		// update the HEAD
+		RefUpdate refUpdate = db.updateRef(Constants.HEAD);
+		refUpdate.link(branchName);
+	}
+
+	public void testFastForwardWithNewFile() throws Exception {
+		Git git = new Git(db);
+
+		// create file1 on master
+		writeTrashFile("file1", "file1");
+		git.add().addFilepattern("file1").call();
+		RevCommit first = git.commit().setMessage("Add file1").call();
+
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		// create a topic branch
+		createBranch(first, "refs/heads/topic");
+		// create file2 on master
+		writeTrashFile("file2", "file2");
+		git.add().addFilepattern("file2").call();
+		git.commit().setMessage("Add file2").call();
+		assertTrue(new File(db.getWorkTree(), "file2").exists());
+
+		checkoutBranch("refs/heads/topic");
+		assertFalse(new File(db.getWorkTree(), "file2").exists());
+
+		RebaseResult res = git.rebase().setUpstream("refs/heads/master").call();
+		assertEquals(Status.UP_TO_DATE, res.getStatus());
+	}
+
+	public void testConflictFreeWithSingleFile() throws Exception {
+		Git git = new Git(db);
+
+		// create file1 on master
+		File theFile = writeTrashFile("file1", "1\n2\n3\n");
+		git.add().addFilepattern("file1").call();
+		RevCommit second = git.commit().setMessage("Add file1").call();
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		// change first line in master and commit
+		writeTrashFile("file1", "1master\n2\n3\n");
+		checkFile(theFile, "1master\n2\n3\n");
+		git.add().addFilepattern("file1").call();
+		RevCommit lastMasterChange = git.commit().setMessage(
+				"change file1 in master").call();
+
+		// create a topic branch based on second commit
+		createBranch(second, "refs/heads/topic");
+		checkoutBranch("refs/heads/topic");
+		// we have the old content again
+		checkFile(theFile, "1\n2\n3\n");
+
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		// change third line in topic branch
+		writeTrashFile("file1", "1\n2\n3\ntopic\n");
+		git.add().addFilepattern("file1").call();
+		git.commit().setMessage("change file1 in topic").call();
+
+		RebaseResult res = git.rebase().setUpstream("refs/heads/master").call();
+		assertEquals(Status.OK, res.getStatus());
+		checkFile(theFile, "1master\n2\n3\ntopic\n");
+		// our old branch should be checked out again
+		assertEquals("refs/heads/topic", db.getFullBranch());
+		assertEquals(lastMasterChange, new RevWalk(db).parseCommit(
+				db.resolve(Constants.HEAD)).getParent(0));
+	}
+
+	public void testFilesAddedFromTwoBranches() throws Exception {
+		Git git = new Git(db);
+
+		// create file1 on master
+		writeTrashFile("file1", "file1");
+		git.add().addFilepattern("file1").call();
+		RevCommit masterCommit = git.commit().setMessage("Add file1 to master")
+				.call();
+
+		// create a branch named file2 and add file2
+		createBranch(masterCommit, "refs/heads/file2");
+		checkoutBranch("refs/heads/file2");
+		writeTrashFile("file2", "file2");
+		git.add().addFilepattern("file2").call();
+		RevCommit addFile2 = git.commit().setMessage(
+				"Add file2 to branch file2").call();
+
+		// create a branch named file3 and add file3
+		createBranch(masterCommit, "refs/heads/file3");
+		checkoutBranch("refs/heads/file3");
+		writeTrashFile("file3", "file3");
+		git.add().addFilepattern("file3").call();
+		git.commit().setMessage("Add file3 to branch file3").call();
+
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		assertFalse(new File(db.getWorkTree(), "file2").exists());
+		assertTrue(new File(db.getWorkTree(), "file3").exists());
+
+		RebaseResult res = git.rebase().setUpstream("refs/heads/file2").call();
+		assertEquals(Status.OK, res.getStatus());
+
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		assertTrue(new File(db.getWorkTree(), "file2").exists());
+		assertTrue(new File(db.getWorkTree(), "file3").exists());
+
+		// our old branch should be checked out again
+		assertEquals("refs/heads/file3", db.getFullBranch());
+		assertEquals(addFile2, new RevWalk(db).parseCommit(
+				db.resolve(Constants.HEAD)).getParent(0));
+
+		checkoutBranch("refs/heads/file2");
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		assertTrue(new File(db.getWorkTree(), "file2").exists());
+		assertFalse(new File(db.getWorkTree(), "file3").exists());
+	}
+
+	public void testAbortOnConflict() throws Exception {
+		Git git = new Git(db);
+
+		// create file1 on master
+		File theFile = writeTrashFile("file1", "1\n2\n3\n");
+		git.add().addFilepattern("file1").call();
+		RevCommit second = git.commit().setMessage("Add file1").call();
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		// change first line in master and commit
+		writeTrashFile("file1", "1master\n2\n3\n");
+		checkFile(theFile, "1master\n2\n3\n");
+		git.add().addFilepattern("file1").call();
+		git.commit().setMessage("change file1 in master").call();
+
+		// create a topic branch based on second commit
+		createBranch(second, "refs/heads/topic");
+		checkoutBranch("refs/heads/topic");
+		// we have the old content again
+		checkFile(theFile, "1\n2\n3\n");
+
+		assertTrue(new File(db.getWorkTree(), "file1").exists());
+		// add a line (non-conflicting)
+		writeTrashFile("file1", "1\n2\n3\n4\n");
+		git.add().addFilepattern("file1").call();
+		git.commit().setMessage("add a line to file1 in topic").call();
+
+		// change first line (conflicting)
+		writeTrashFile("file1", "1topic\n2\n3\n4\n");
+		git.add().addFilepattern("file1").call();
+		git.commit().setMessage("change file1 in topic").call();
+
+		// change second line (not conflicting)
+		writeTrashFile("file1", "1topic\n2topic\n3\n4\n");
+		git.add().addFilepattern("file1").call();
+		RevCommit lastTopicCommit = git.commit().setMessage(
+				"change file1 in topic again").call();
+
+		RebaseResult res = git.rebase().setUpstream("refs/heads/master").call();
+		assertEquals(Status.STOPPED, res.getStatus());
+		checkFile(theFile,
+				"<<<<<<< OURS\n1master\n=======\n1topic\n>>>>>>> THEIRS\n2\n3\n4\n");
+
+		assertEquals(RepositoryState.REBASING_MERGE, db.getRepositoryState());
+		// the first one should be included, so we should have left two picks in
+		// the file
+		assertEquals(countPicks(), 2);
+		// abort should reset to topic branch
+		res = git.rebase().setOperation(Operation.ABORT).call();
+		assertEquals(res.getStatus(), Status.ABORTED);
+		assertEquals("refs/heads/topic", db.getFullBranch());
+		checkFile(theFile, "1topic\n2topic\n3\n4\n");
+		RevWalk rw = new RevWalk(db);
+		assertEquals(lastTopicCommit, rw
+				.parseCommit(db.resolve(Constants.HEAD)));
+	}
+
+	private int countPicks() throws IOException {
+		int count = 0;
+		File todoFile = new File(db.getDirectory(),
+				"rebase-merge/git-rebase-todo");
+		BufferedReader br = new BufferedReader(new InputStreamReader(
+				new FileInputStream(todoFile), "UTF-8"));
+		try {
+			String line = br.readLine();
+			while (line != null) {
+				if (line.startsWith("pick "))
+					count++;
+				line = br.readLine();
+			}
+			return count;
+		} finally {
+			br.close();
+		}
+	}
+}