Merge "Implement a revert command"

org.eclipse.jgit.test/tst/org/eclipse/jgit/api/RevertCommandTest.java

@@ -0,0 +1,101 @@
+/*
+ * Copyright (C) 2011, Robin Rosenberg
+ * 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 static org.junit.Assert.*;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Iterator;
+
+import org.eclipse.jgit.api.errors.GitAPIException;
+import org.eclipse.jgit.api.errors.JGitInternalException;
+import org.eclipse.jgit.lib.RepositoryTestCase;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.junit.Test;
+
+/**
+ * Test cherry-pick command
+ */
+public class RevertCommandTest extends RepositoryTestCase {
+	@Test
+	public void testRevert() throws IOException, JGitInternalException,
+			GitAPIException {
+		Git git = new Git(db);
+
+		writeTrashFile("a", "first line\nsec. line\nthird line\n");
+		git.add().addFilepattern("a").call();
+		git.commit().setMessage("create a").call();
+
+		writeTrashFile("b", "content\n");
+		git.add().addFilepattern("b").call();
+		git.commit().setMessage("create b").call();
+
+		writeTrashFile("a", "first line\nsec. line\nthird line\nfourth line\n");
+		git.add().addFilepattern("a").call();
+		git.commit().setMessage("enlarged a").call();
+
+		writeTrashFile("a",
+				"first line\nsecond line\nthird line\nfourth line\n");
+		git.add().addFilepattern("a").call();
+		RevCommit fixingA = git.commit().setMessage("fixed a").call();
+
+		writeTrashFile("b", "first line\n");
+		git.add().addFilepattern("b").call();
+		git.commit().setMessage("fixed b").call();
+
+		git.revert().include(fixingA).call();
+
+		assertTrue(new File(db.getWorkTree(), "b").exists());
+		checkFile(new File(db.getWorkTree(), "a"),
+				"first line\nsec. line\nthird line\nfourth line\n");
+		Iterator<RevCommit> history = git.log().call().iterator();
+		assertEquals("Revert \"fixed a\"", history.next().getShortMessage());
+		assertEquals("fixed b", history.next().getFullMessage());
+		assertEquals("fixed a", history.next().getFullMessage());
+		assertEquals("enlarged a", history.next().getFullMessage());
+		assertEquals("create b", history.next().getFullMessage());
+		assertEquals("create a", history.next().getFullMessage());
+		assertFalse(history.hasNext());
+	}
+}

org.eclipse.jgit.test/tst/org/eclipse/jgit/merge/CherryPickTest.java

@@ -128,6 +128,64 @@ public class CherryPickTest extends RepositoryTestCase {
 		assertFalse(tw.next());
 	}
 
+	@Test
+	public void testRevert() throws Exception {
+		// B---P---T
+		//
+		// Revert P, this should result in a tree with a
+		// from B and t from T as the change to a in P
+		// and addition of t in P is reverted.
+		//
+		// We use the standard merge, but change the order
+		// of the sources.
+		//
+		final DirCache treeB = db.readDirCache();
+		final DirCache treeP = db.readDirCache();
+		final DirCache treeT = db.readDirCache();
+		{
+			final DirCacheBuilder b = treeB.builder();
+			final DirCacheBuilder p = treeP.builder();
+			final DirCacheBuilder t = treeT.builder();
+
+			b.add(makeEntry("a", FileMode.REGULAR_FILE));
+
+			p.add(makeEntry("a", FileMode.REGULAR_FILE, "q"));
+			p.add(makeEntry("p-fail", FileMode.REGULAR_FILE));
+
+			t.add(makeEntry("a", FileMode.REGULAR_FILE, "q"));
+			t.add(makeEntry("p-fail", FileMode.REGULAR_FILE));
+			t.add(makeEntry("t", FileMode.REGULAR_FILE));
+
+			b.finish();
+			p.finish();
+			t.finish();
+		}
+
+		final ObjectInserter ow = db.newObjectInserter();
+		final ObjectId B = commit(ow, treeB, new ObjectId[] {});
+		final ObjectId P = commit(ow, treeP, new ObjectId[] { B });
+		final ObjectId T = commit(ow, treeT, new ObjectId[] { P });
+
+		ThreeWayMerger twm = MergeStrategy.SIMPLE_TWO_WAY_IN_CORE.newMerger(db);
+		twm.setBase(P);
+		boolean merge = twm.merge(new ObjectId[] { B, T });
+		assertTrue(merge);
+
+		final TreeWalk tw = new TreeWalk(db);
+		tw.setRecursive(true);
+		tw.reset(twm.getResultTreeId());
+
+		assertTrue(tw.next());
+		assertEquals("a", tw.getPathString());
+		assertCorrectId(treeB, tw);
+
+		assertTrue(tw.next());
+		assertEquals("t", tw.getPathString());
+		assertCorrectId(treeT, tw);
+
+		assertFalse(tw.next());
+	}
+
 	private void assertCorrectId(final DirCache treeT, final TreeWalk tw) {
 		assertEquals(treeT.getEntry(tw.getPathString()).getObjectId(), tw
 				.getObjectId(0));

org.eclipse.jgit/resources/org/eclipse/jgit/JGitText.properties

@@ -75,6 +75,7 @@ cannotStoreObjects=cannot store objects
 cannotUnloadAModifiedTree=Cannot unload a modified tree.
 cannotWorkWithOtherStagesThanZeroRightNow=Cannot work with other stages than zero right now. Won't write corrupt index.
 canOnlyCherryPickCommitsWithOneParent=Can only cherry-pick commits which have exactly one parent
+canOnlyRevertCommitsWithOneParent=Can only revert commits which have exactly one parent
 cantFindObjectInReversePackIndexForTheSpecifiedOffset=Can't find object in (reverse) pack index for the specified offset {0}
 cantPassMeATree=Can't pass me a tree!
 channelMustBeInRange0_255=channel {0} must be in range [0, 255]
@@ -171,6 +172,7 @@ exceptionCaughtDuringExecutionOfFetchCommand=Exception caught during execution o
 exceptionCaughtDuringExecutionOfMergeCommand=Exception caught during execution of merge command. {0}
 exceptionCaughtDuringExecutionOfPushCommand=Exception caught during execution of push command
 exceptionCaughtDuringExecutionOfPullCommand=Exception caught during execution of pull command
+exceptionCaughtDuringExecutionOfRevertCommand=Exception caught during execution of revert command. {0}
 exceptionCaughtDuringExecutionOfRmCommand=Exception caught during execution of rm command
 exceptionCaughtDuringExecutionOfTagCommand=Exception caught during execution of tag command
 exceptionOccuredDuringAddingOfOptionToALogCommand=Exception occured during adding of {0} as option to a Log command

org.eclipse.jgit/src/org/eclipse/jgit/JGitText.java

@@ -135,6 +135,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String cannotUnloadAModifiedTree;
 	/***/ public String cannotWorkWithOtherStagesThanZeroRightNow;
 	/***/ public String canOnlyCherryPickCommitsWithOneParent;
+	/***/ public String canOnlyRevertCommitsWithOneParent;
 	/***/ public String cantFindObjectInReversePackIndexForTheSpecifiedOffset;
 	/***/ public String cantPassMeATree;
 	/***/ public String channelMustBeInRange0_255;
@@ -231,6 +232,7 @@ public class JGitText extends TranslationBundle {
 	/***/ public String exceptionCaughtDuringExecutionOfMergeCommand;
 	/***/ public String exceptionCaughtDuringExecutionOfPushCommand;
 	/***/ public String exceptionCaughtDuringExecutionOfPullCommand;
+	/***/ public String exceptionCaughtDuringExecutionOfRevertCommand;
 	/***/ public String exceptionCaughtDuringExecutionOfRmCommand;
 	/***/ public String exceptionCaughtDuringExecutionOfTagCommand;
 	/***/ public String exceptionOccuredDuringAddingOfOptionToALogCommand;

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

@@ -256,6 +256,19 @@ public class Git {
 		return new CherryPickCommand(repo);
 	}
 
+	/**
+	 * Returns a command object to execute a {@code revert} command
+	 *
+	 * @see <a
+	 *      href="http://www.kernel.org/pub/software/scm/git/docs/git-revert.html"
+	 *      >Git documentation about reverting changes</a>
+	 * @return a {@link RevertCommand} used to collect all optional
+	 *         parameters and to finally execute the {@code cherry-pick} command
+	 */
+	public RevertCommand revert() {
+		return new RevertCommand(repo);
+	}
+
 	/**
 	 * Returns a command object to execute a {@code Rebase} command
 	 *

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

@@ -0,0 +1,207 @@
+/*
+ * Copyright (C) 2010, Christian Halstrick <christian.halstrick@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.IOException;
+import java.text.MessageFormat;
+import java.util.LinkedList;
+import java.util.List;
+
+import org.eclipse.jgit.JGitText;
+import org.eclipse.jgit.api.errors.GitAPIException;
+import org.eclipse.jgit.api.errors.MultipleParentsNotAllowedException;
+import org.eclipse.jgit.api.errors.JGitInternalException;
+import org.eclipse.jgit.api.errors.NoHeadException;
+import org.eclipse.jgit.dircache.DirCacheCheckout;
+import org.eclipse.jgit.lib.AnyObjectId;
+import org.eclipse.jgit.lib.Constants;
+import org.eclipse.jgit.lib.ObjectId;
+import org.eclipse.jgit.lib.ObjectIdRef;
+import org.eclipse.jgit.lib.Ref;
+import org.eclipse.jgit.lib.Ref.Storage;
+import org.eclipse.jgit.lib.Repository;
+import org.eclipse.jgit.merge.MergeStrategy;
+import org.eclipse.jgit.merge.ResolveMerger;
+import org.eclipse.jgit.revwalk.RevCommit;
+import org.eclipse.jgit.revwalk.RevWalk;
+import org.eclipse.jgit.treewalk.FileTreeIterator;
+
+/**
+ * A class used to execute a {@code revert} command. It has setters for all
+ * supported options and arguments of this command and a {@link #call()} method
+ * to finally execute the command. Each instance of this class should only be
+ * used for one invocation of the command (means: one call to {@link #call()})
+ *
+ * @see <a
+ *      href="http://www.kernel.org/pub/software/scm/git/docs/git-revert.html"
+ *      >Git documentation about revert</a>
+ */
+public class RevertCommand extends GitCommand<RevCommit> {
+	private List<Ref> commits = new LinkedList<Ref>();
+
+	private List<Ref> revertedRefs = new LinkedList<Ref>();
+
+	/**
+	 * @param repo
+	 */
+	protected RevertCommand(Repository repo) {
+		super(repo);
+	}
+
+	/**
+	 * Executes the {@code revert} command with all the options and parameters
+	 * collected by the setter methods (e.g. {@link #include(Ref)} of this
+	 * class. Each instance of this class should only be used for one invocation
+	 * of the command. Don't call this method twice on an instance.
+	 *
+	 * @return on success the {@link RevCommit} pointed to by the new HEAD is
+	 *         returned. If a failure occurred during revert <code>null</code>
+	 *         is returned. The list of successfully reverted {@link Ref}'s can
+	 *         be obtained by calling {@link #getRevertedRefs()}
+	 */
+	public RevCommit call() throws GitAPIException {
+		RevCommit newHead = null;
+		checkCallable();
+
+		RevWalk revWalk = new RevWalk(repo);
+		try {
+
+			// get the head commit
+			Ref headRef = repo.getRef(Constants.HEAD);
+			if (headRef == null)
+				throw new NoHeadException(
+						JGitText.get().commitOnRepoWithoutHEADCurrentlyNotSupported);
+			RevCommit headCommit = revWalk.parseCommit(headRef.getObjectId());
+
+			// loop through all refs to be reverted
+			for (Ref src : commits) {
+				// get the commit to be reverted
+				// handle annotated tags
+				ObjectId srcObjectId = src.getPeeledObjectId();
+				if (srcObjectId == null)
+					srcObjectId = src.getObjectId();
+				RevCommit srcCommit = revWalk.parseCommit(srcObjectId);
+
+				// get the parent of the commit to revert
+				if (srcCommit.getParentCount() != 1) {
+					throw new MultipleParentsNotAllowedException(
+							JGitText.get().canOnlyRevertCommitsWithOneParent);
+				}
+				RevCommit srcParent = srcCommit.getParent(0);
+				revWalk.parseHeaders(srcParent);
+
+				ResolveMerger merger = (ResolveMerger) MergeStrategy.RESOLVE
+						.newMerger(repo);
+				merger.setWorkingTreeIterator(new FileTreeIterator(repo));
+				merger.setBase(srcCommit.getTree());
+
+				if (merger.merge(headCommit, srcParent)) {
+					DirCacheCheckout dco = new DirCacheCheckout(repo,
+							headCommit.getTree(), repo.lockDirCache(),
+							merger.getResultTreeId());
+					dco.setFailOnConflict(true);
+					dco.checkout();
+					String newMessage = "Revert \""
+							+ srcCommit.getShortMessage() + "\"" + "\n\n"
+							+ "This reverts commit "
+							+ srcCommit.getId().getName() + "\n";
+					newHead = new Git(getRepository()).commit().setMessage(
+							newMessage).call();
+					revertedRefs.add(src);
+				} else {
+					return null;
+				}
+			}
+		} catch (IOException e) {
+			throw new JGitInternalException(
+					MessageFormat.format(
+									JGitText.get().exceptionCaughtDuringExecutionOfRevertCommand,
+							e), e);
+		} finally {
+			revWalk.release();
+		}
+		return newHead;
+	}
+
+	/**
+	 * @param commit
+	 *            a reference to a commit which is reverted into the current
+	 *            head
+	 * @return {@code this}
+	 */
+	public RevertCommand include(Ref commit) {
+		checkCallable();
+		commits.add(commit);
+		return this;
+	}
+
+	/**
+	 * @param commit
+	 *            the Id of a commit which is reverted into the current head
+	 * @return {@code this}
+	 */
+	public RevertCommand include(AnyObjectId commit) {
+		return include(commit.getName(), commit);
+	}
+
+	/**
+	 * @param name
+	 *            a name given to the commit
+	 * @param commit
+	 *            the Id of a commit which is reverted into the current head
+	 * @return {@code this}
+	 */
+	public RevertCommand include(String name, AnyObjectId commit) {
+		return include(new ObjectIdRef.Unpeeled(Storage.LOOSE, name,
+				commit.copy()));
+	}
+
+	/**
+	 * @return the list of successfully reverted {@link Ref}'s. Never
+	 *         <code>null</code> but maybe an empty list if no commit was
+	 *         successfully cherry-picked
+	 */
+	public List<Ref> getRevertedRefs() {
+		return revertedRefs;
+	}
+}