CherryPickCommand.java
/*
* Copyright (C) 2010, 2021 Christian Halstrick <christian.halstrick@sap.com> and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.api;
import static org.eclipse.jgit.lib.Constants.OBJECT_ID_ABBREV_STRING_LENGTH;
import java.io.IOException;
import java.text.MessageFormat;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import org.eclipse.jgit.api.errors.ConcurrentRefUpdateException;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.api.errors.JGitInternalException;
import org.eclipse.jgit.api.errors.MultipleParentsNotAllowedException;
import org.eclipse.jgit.api.errors.NoHeadException;
import org.eclipse.jgit.api.errors.NoMessageException;
import org.eclipse.jgit.api.errors.UnmergedPathsException;
import org.eclipse.jgit.api.errors.WrongRepositoryStateException;
import org.eclipse.jgit.dircache.DirCacheCheckout;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.events.WorkingTreeModifiedEvent;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.CommitConfig;
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.Repository;
import org.eclipse.jgit.merge.ContentMergeStrategy;
import org.eclipse.jgit.merge.MergeMessageFormatter;
import org.eclipse.jgit.merge.MergeStrategy;
import org.eclipse.jgit.merge.Merger;
import org.eclipse.jgit.merge.ResolveMerger;
import org.eclipse.jgit.merge.ResolveMerger.MergeFailureReason;
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 cherry-pick} 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-cherry-pick.html"
* >Git documentation about cherry-pick</a>
*/
public class CherryPickCommand extends GitCommand<CherryPickResult> {
private String reflogPrefix = "cherry-pick:"; //$NON-NLS-1$
private List<Ref> commits = new LinkedList<>();
private String ourCommitName = null;
private MergeStrategy strategy = MergeStrategy.RECURSIVE;
private ContentMergeStrategy contentStrategy;
private Integer mainlineParentNumber;
private boolean noCommit = false;
private ProgressMonitor monitor = NullProgressMonitor.INSTANCE;
/**
* Constructor for CherryPickCommand
*
* @param repo
* the {@link org.eclipse.jgit.lib.Repository}
*/
protected CherryPickCommand(Repository repo) {
super(repo);
}
/**
* {@inheritDoc}
* <p>
* Executes the {@code Cherry-Pick} 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.
*/
@Override
public CherryPickResult call() throws GitAPIException, NoMessageException,
UnmergedPathsException, ConcurrentRefUpdateException,
WrongRepositoryStateException, NoHeadException {
RevCommit newHead = null;
List<Ref> cherryPickedRefs = new LinkedList<>();
checkCallable();
try (RevWalk revWalk = new RevWalk(repo)) {
// get the head commit
Ref headRef = repo.exactRef(Constants.HEAD);
if (headRef == null) {
throw new NoHeadException(
JGitText.get().commitOnRepoWithoutHEADCurrentlyNotSupported);
}
newHead = revWalk.parseCommit(headRef.getObjectId());
// loop through all refs to be cherry-picked
for (Ref src : commits) {
// get the commit to be cherry-picked
// 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 cherry-pick
final RevCommit srcParent = getParentCommit(srcCommit, revWalk);
String ourName = calculateOurName(headRef);
String cherryPickName = srcCommit.getId().abbreviate(OBJECT_ID_ABBREV_STRING_LENGTH).name()
+ " " + srcCommit.getShortMessage(); //$NON-NLS-1$
Merger merger = strategy.newMerger(repo);
merger.setProgressMonitor(monitor);
boolean noProblems;
Map<String, MergeFailureReason> failingPaths = null;
List<String> unmergedPaths = null;
if (merger instanceof ResolveMerger) {
ResolveMerger resolveMerger = (ResolveMerger) merger;
resolveMerger.setContentMergeStrategy(contentStrategy);
resolveMerger.setCommitNames(
new String[] { "BASE", ourName, cherryPickName }); //$NON-NLS-1$
resolveMerger
.setWorkingTreeIterator(new FileTreeIterator(repo));
resolveMerger.setBase(srcParent.getTree());
noProblems = merger.merge(newHead, srcCommit);
failingPaths = resolveMerger.getFailingPaths();
unmergedPaths = resolveMerger.getUnmergedPaths();
if (!resolveMerger.getModifiedFiles().isEmpty()) {
repo.fireEvent(new WorkingTreeModifiedEvent(
resolveMerger.getModifiedFiles(), null));
}
} else {
noProblems = merger.merge(newHead, srcCommit);
}
if (noProblems) {
if (AnyObjectId.isEqual(newHead.getTree().getId(),
merger.getResultTreeId())) {
continue;
}
DirCacheCheckout dco = new DirCacheCheckout(repo,
newHead.getTree(), repo.lockDirCache(),
merger.getResultTreeId());
dco.setFailOnConflict(true);
dco.setProgressMonitor(monitor);
dco.checkout();
if (!noCommit) {
try (Git git = new Git(getRepository())) {
newHead = git.commit()
.setMessage(srcCommit.getFullMessage())
.setReflogComment(reflogPrefix + " " //$NON-NLS-1$
+ srcCommit.getShortMessage())
.setAuthor(srcCommit.getAuthorIdent())
.setNoVerify(true).call();
}
}
cherryPickedRefs.add(src);
} else {
if (failingPaths != null && !failingPaths.isEmpty()) {
return new CherryPickResult(failingPaths);
}
// there are merge conflicts
String message;
if (unmergedPaths != null) {
CommitConfig cfg = repo.getConfig()
.get(CommitConfig.KEY);
message = srcCommit.getFullMessage();
char commentChar = cfg.getCommentChar(message);
message = new MergeMessageFormatter()
.formatWithConflicts(message, unmergedPaths,
commentChar);
} else {
message = srcCommit.getFullMessage();
}
if (!noCommit) {
repo.writeCherryPickHead(srcCommit.getId());
}
repo.writeMergeCommitMsg(message);
return CherryPickResult.CONFLICT;
}
}
} catch (IOException e) {
throw new JGitInternalException(
MessageFormat.format(
JGitText.get().exceptionCaughtDuringExecutionOfCherryPickCommand,
e), e);
}
return new CherryPickResult(newHead, cherryPickedRefs);
}
private RevCommit getParentCommit(RevCommit srcCommit, RevWalk revWalk)
throws MultipleParentsNotAllowedException, MissingObjectException,
IOException {
final RevCommit srcParent;
if (mainlineParentNumber == null) {
if (srcCommit.getParentCount() != 1)
throw new MultipleParentsNotAllowedException(
MessageFormat.format(
JGitText.get().canOnlyCherryPickCommitsWithOneParent,
srcCommit.name(),
Integer.valueOf(srcCommit.getParentCount())));
srcParent = srcCommit.getParent(0);
} else {
if (mainlineParentNumber.intValue() > srcCommit.getParentCount()) {
throw new JGitInternalException(MessageFormat.format(
JGitText.get().commitDoesNotHaveGivenParent, srcCommit,
mainlineParentNumber));
}
srcParent = srcCommit
.getParent(mainlineParentNumber.intValue() - 1);
}
revWalk.parseHeaders(srcParent);
return srcParent;
}
/**
* Include a reference to a commit
*
* @param commit
* a reference to a commit which is cherry-picked to the current
* head
* @return {@code this}
*/
public CherryPickCommand include(Ref commit) {
checkCallable();
commits.add(commit);
return this;
}
/**
* Include a commit
*
* @param commit
* the Id of a commit which is cherry-picked to the current head
* @return {@code this}
*/
public CherryPickCommand include(AnyObjectId commit) {
return include(commit.getName(), commit);
}
/**
* Include a commit
*
* @param name
* a name given to the commit
* @param commit
* the Id of a commit which is cherry-picked to the current head
* @return {@code this}
*/
public CherryPickCommand include(String name, AnyObjectId commit) {
return include(new ObjectIdRef.Unpeeled(Storage.LOOSE, name,
commit.copy()));
}
/**
* Set the name that should be used in the "OURS" place for conflict markers
*
* @param ourCommitName
* the name that should be used in the "OURS" place for conflict
* markers
* @return {@code this}
*/
public CherryPickCommand setOurCommitName(String ourCommitName) {
this.ourCommitName = ourCommitName;
return this;
}
/**
* Set the prefix to use in the reflog.
* <p>
* This is primarily needed for implementing rebase in terms of
* cherry-picking
*
* @param prefix
* including ":"
* @return {@code this}
* @since 3.1
*/
public CherryPickCommand setReflogPrefix(String prefix) {
this.reflogPrefix = prefix;
return this;
}
/**
* Set the {@code MergeStrategy}
*
* @param strategy
* The merge strategy to use during this Cherry-pick.
* @return {@code this}
* @since 3.4
*/
public CherryPickCommand setStrategy(MergeStrategy strategy) {
this.strategy = strategy;
return this;
}
/**
* Sets the content merge strategy to use if the
* {@link #setStrategy(MergeStrategy) merge strategy} is "resolve" or
* "recursive".
*
* @param strategy
* the {@link ContentMergeStrategy} to be used
* @return {@code this}
* @since 5.12
*/
public CherryPickCommand setContentMergeStrategy(
ContentMergeStrategy strategy) {
this.contentStrategy = strategy;
return this;
}
/**
* Set the (1-based) parent number to diff against
*
* @param mainlineParentNumber
* the (1-based) parent number to diff against. This allows
* cherry-picking of merges.
* @return {@code this}
* @since 3.4
*/
public CherryPickCommand setMainlineParentNumber(int mainlineParentNumber) {
this.mainlineParentNumber = Integer.valueOf(mainlineParentNumber);
return this;
}
/**
* Allows cherry-picking changes without committing them.
* <p>
* NOTE: The behavior of cherry-pick is undefined if you pick multiple
* commits or if HEAD does not match the index state before cherry-picking.
*
* @param noCommit
* true to cherry-pick without committing, false to commit after
* each pick (default)
* @return {@code this}
* @since 3.5
*/
public CherryPickCommand setNoCommit(boolean noCommit) {
this.noCommit = noCommit;
return this;
}
/**
* The progress monitor associated with the cherry-pick operation. By
* default, this is set to <code>NullProgressMonitor</code>
*
* @see NullProgressMonitor
* @param monitor
* a {@link org.eclipse.jgit.lib.ProgressMonitor}
* @return {@code this}
* @since 4.11
*/
public CherryPickCommand setProgressMonitor(ProgressMonitor monitor) {
if (monitor == null) {
monitor = NullProgressMonitor.INSTANCE;
}
this.monitor = monitor;
return this;
}
private String calculateOurName(Ref headRef) {
if (ourCommitName != null)
return ourCommitName;
String targetRefName = headRef.getTarget().getName();
String headName = Repository.shortenRefName(targetRefName);
return headName;
}
/** {@inheritDoc} */
@SuppressWarnings("nls")
@Override
public String toString() {
return "CherryPickCommand [repo=" + repo + ",\ncommits=" + commits
+ ",\nmainlineParentNumber=" + mainlineParentNumber
+ ", noCommit=" + noCommit + ", ourCommitName=" + ourCommitName
+ ", reflogPrefix=" + reflogPrefix + ", strategy=" + strategy
+ "]";
}
}