org.eclipse.jgit.api.CloneCommand.java Source code

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/*
 * Copyright (C) 2011, 2017 Chris Aniszczyk <caniszczyk@gmail.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.File;
import java.io.IOException;
import java.net.URISyntaxException;
import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;

import org.eclipse.jgit.annotations.Nullable;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.api.errors.InvalidRemoteException;
import org.eclipse.jgit.api.errors.JGitInternalException;
import org.eclipse.jgit.dircache.DirCache;
import org.eclipse.jgit.dircache.DirCacheCheckout;
import org.eclipse.jgit.errors.IncorrectObjectTypeException;
import org.eclipse.jgit.errors.MissingObjectException;
import org.eclipse.jgit.internal.JGitText;
import org.eclipse.jgit.lib.AnyObjectId;
import org.eclipse.jgit.lib.BranchConfig.BranchRebaseMode;
import org.eclipse.jgit.lib.ConfigConstants;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.NullProgressMonitor;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ProgressMonitor;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.RefUpdate;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.revwalk.RevWalk;
import org.eclipse.jgit.submodule.SubmoduleWalk;
import org.eclipse.jgit.transport.FetchResult;
import org.eclipse.jgit.transport.RefSpec;
import org.eclipse.jgit.transport.RemoteConfig;
import org.eclipse.jgit.transport.TagOpt;
import org.eclipse.jgit.transport.URIish;
import org.eclipse.jgit.util.FS;
import org.eclipse.jgit.util.FileUtils;

/**
 * Clone a repository into a new working directory
 *
 * @see <a href="http://www.kernel.org/pub/software/scm/git/docs/git-clone.html"
 *      >Git documentation about Clone</a>
 */
public class CloneCommand extends TransportCommand<CloneCommand, Git> {

    private String uri;

    private File directory;

    private File gitDir;

    private boolean bare;

    private FS fs;

    private String remote = Constants.DEFAULT_REMOTE_NAME;

    private String branch = Constants.HEAD;

    private ProgressMonitor monitor = NullProgressMonitor.INSTANCE;

    private FETCH_TYPE fetchType = FETCH_TYPE.ALL_BRANCHES;

    private boolean cloneSubmodules;

    private boolean noCheckout;

    private Collection<String> branchesToClone;

    private Callback callback;

    private boolean directoryExistsInitially;

    private boolean gitDirExistsInitially;

    private enum FETCH_TYPE {
        MULTIPLE_BRANCHES, ALL_BRANCHES, MIRROR
    }

    /**
     * Callback for status of clone operation.
     *
     * @since 4.8
     */
    public interface Callback {
        /**
         * Notify initialized submodules.
         *
         * @param submodules
         *            the submodules
         *
         */
        void initializedSubmodules(Collection<String> submodules);

        /**
         * Notify starting to clone a submodule.
         *
         * @param path
         *            the submodule path
         */
        void cloningSubmodule(String path);

        /**
         * Notify checkout of commit
         *
         * @param commit
         *            the id of the commit being checked out
         * @param path
         *            the submodule path
         */
        void checkingOut(AnyObjectId commit, String path);
    }

    /**
     * Create clone command with no repository set
     */
    public CloneCommand() {
        super(null);
    }

    /**
     * Get the git directory. This is primarily used for tests.
     *
     * @return the git directory
     */
    @Nullable
    File getDirectory() {
        return directory;
    }

    /**
     * {@inheritDoc}
     * <p>
     * Executes the {@code Clone} command.
     *
     * The Git instance returned by this command needs to be closed by the
     * caller to free resources held by the underlying {@link Repository}
     * instance. It is recommended to call this method as soon as you don't need
     * a reference to this {@link Git} instance and the underlying
     * {@link Repository} instance anymore.
     */
    @Override
    public Git call()
            throws GitAPIException, InvalidRemoteException, org.eclipse.jgit.api.errors.TransportException {
        URIish u = null;
        try {
            u = new URIish(uri);
            verifyDirectories(u);
        } catch (URISyntaxException e) {
            throw new InvalidRemoteException(MessageFormat.format(JGitText.get().invalidURL, uri));
        }
        @SuppressWarnings("resource") // Closed by caller
        Repository repository = init();
        FetchResult fetchResult = null;
        Thread cleanupHook = new Thread(() -> cleanup());
        Runtime.getRuntime().addShutdownHook(cleanupHook);
        try {
            fetchResult = fetch(repository, u);
        } catch (IOException ioe) {
            if (repository != null) {
                repository.close();
            }
            cleanup();
            throw new JGitInternalException(ioe.getMessage(), ioe);
        } catch (URISyntaxException e) {
            if (repository != null) {
                repository.close();
            }
            cleanup();
            throw new InvalidRemoteException(MessageFormat.format(JGitText.get().invalidRemote, remote));
        } catch (GitAPIException | RuntimeException e) {
            if (repository != null) {
                repository.close();
            }
            cleanup();
            throw e;
        } finally {
            Runtime.getRuntime().removeShutdownHook(cleanupHook);
        }
        if (!noCheckout) {
            try {
                checkout(repository, fetchResult);
            } catch (IOException ioe) {
                repository.close();
                throw new JGitInternalException(ioe.getMessage(), ioe);
            } catch (GitAPIException | RuntimeException e) {
                repository.close();
                throw e;
            }
        }
        return new Git(repository, true);
    }

    private static boolean isNonEmptyDirectory(File dir) {
        if (dir != null && dir.exists()) {
            File[] files = dir.listFiles();
            return files != null && files.length != 0;
        }
        return false;
    }

    void verifyDirectories(URIish u) {
        if (directory == null && gitDir == null) {
            directory = new File(u.getHumanishName() + (bare ? Constants.DOT_GIT_EXT : "")); //$NON-NLS-1$
        }
        directoryExistsInitially = directory != null && directory.exists();
        gitDirExistsInitially = gitDir != null && gitDir.exists();
        validateDirs(directory, gitDir, bare);
        if (isNonEmptyDirectory(directory)) {
            throw new JGitInternalException(
                    MessageFormat.format(JGitText.get().cloneNonEmptyDirectory, directory.getName()));
        }
        if (isNonEmptyDirectory(gitDir)) {
            throw new JGitInternalException(
                    MessageFormat.format(JGitText.get().cloneNonEmptyDirectory, gitDir.getName()));
        }
    }

    private Repository init() throws GitAPIException {
        InitCommand command = Git.init();
        command.setBare(bare);
        if (fs != null) {
            command.setFs(fs);
        }
        if (directory != null) {
            command.setDirectory(directory);
        }
        if (gitDir != null) {
            command.setGitDir(gitDir);
        }
        return command.call().getRepository();
    }

    private FetchResult fetch(Repository clonedRepo, URIish u) throws URISyntaxException,
            org.eclipse.jgit.api.errors.TransportException, IOException, GitAPIException {
        // create the remote config and save it
        RemoteConfig config = new RemoteConfig(clonedRepo.getConfig(), remote);
        config.addURI(u);

        boolean fetchAll = fetchType == FETCH_TYPE.ALL_BRANCHES || fetchType == FETCH_TYPE.MIRROR;

        config.setFetchRefSpecs(calculateRefSpecs(fetchType, config.getName()));
        config.setMirror(fetchType == FETCH_TYPE.MIRROR);
        config.update(clonedRepo.getConfig());

        clonedRepo.getConfig().save();

        // run the fetch command
        FetchCommand command = new FetchCommand(clonedRepo);
        command.setRemote(remote);
        command.setProgressMonitor(monitor);
        command.setTagOpt(fetchAll ? TagOpt.FETCH_TAGS : TagOpt.AUTO_FOLLOW);
        configure(command);

        return command.call();
    }

    private List<RefSpec> calculateRefSpecs(FETCH_TYPE type, String remoteName) {
        List<RefSpec> specs = new ArrayList<>();
        if (type == FETCH_TYPE.MIRROR) {
            specs.add(new RefSpec().setForceUpdate(true).setSourceDestination(Constants.R_REFS + '*',
                    Constants.R_REFS + '*'));
        } else {
            RefSpec heads = new RefSpec();
            heads = heads.setForceUpdate(true);
            final String dst = (bare ? Constants.R_HEADS : Constants.R_REMOTES + remoteName + '/') + '*';
            heads = heads.setSourceDestination(Constants.R_HEADS + '*', dst);
            if (type == FETCH_TYPE.MULTIPLE_BRANCHES) {
                RefSpec tags = new RefSpec().setForceUpdate(true).setSourceDestination(Constants.R_TAGS + '*',
                        Constants.R_TAGS + '*');
                for (String selectedRef : branchesToClone) {
                    if (heads.matchSource(selectedRef)) {
                        specs.add(heads.expandFromSource(selectedRef));
                    } else if (tags.matchSource(selectedRef)) {
                        specs.add(tags.expandFromSource(selectedRef));
                    }
                }
            } else {
                // We'll fetch the tags anyway.
                specs.add(heads);
            }
        }
        return specs;
    }

    private void checkout(Repository clonedRepo, FetchResult result)
            throws MissingObjectException, IncorrectObjectTypeException, IOException, GitAPIException {

        Ref head = null;
        if (branch.equals(Constants.HEAD)) {
            Ref foundBranch = findBranchToCheckout(result);
            if (foundBranch != null)
                head = foundBranch;
        }
        if (head == null) {
            head = result.getAdvertisedRef(branch);
            if (head == null)
                head = result.getAdvertisedRef(Constants.R_HEADS + branch);
            if (head == null)
                head = result.getAdvertisedRef(Constants.R_TAGS + branch);
        }

        if (head == null || head.getObjectId() == null)
            return; // TODO throw exception?

        if (head.getName().startsWith(Constants.R_HEADS)) {
            final RefUpdate newHead = clonedRepo.updateRef(Constants.HEAD);
            newHead.disableRefLog();
            newHead.link(head.getName());
            addMergeConfig(clonedRepo, head);
        }

        final RevCommit commit = parseCommit(clonedRepo, head);

        boolean detached = !head.getName().startsWith(Constants.R_HEADS);
        RefUpdate u = clonedRepo.updateRef(Constants.HEAD, detached);
        u.setNewObjectId(commit.getId());
        u.forceUpdate();

        if (!bare) {
            DirCache dc = clonedRepo.lockDirCache();
            DirCacheCheckout co = new DirCacheCheckout(clonedRepo, dc, commit.getTree());
            co.setProgressMonitor(monitor);
            co.checkout();
            if (cloneSubmodules)
                cloneSubmodules(clonedRepo);
        }
    }

    private void cloneSubmodules(Repository clonedRepo) throws IOException, GitAPIException {
        SubmoduleInitCommand init = new SubmoduleInitCommand(clonedRepo);
        Collection<String> submodules = init.call();
        if (submodules.isEmpty()) {
            return;
        }
        if (callback != null) {
            callback.initializedSubmodules(submodules);
        }

        SubmoduleUpdateCommand update = new SubmoduleUpdateCommand(clonedRepo);
        configure(update);
        update.setProgressMonitor(monitor);
        update.setCallback(callback);
        if (!update.call().isEmpty()) {
            SubmoduleWalk walk = SubmoduleWalk.forIndex(clonedRepo);
            while (walk.next()) {
                try (Repository subRepo = walk.getRepository()) {
                    if (subRepo != null) {
                        cloneSubmodules(subRepo);
                    }
                }
            }
        }
    }

    private Ref findBranchToCheckout(FetchResult result) {
        final Ref idHEAD = result.getAdvertisedRef(Constants.HEAD);
        ObjectId headId = idHEAD != null ? idHEAD.getObjectId() : null;
        if (headId == null) {
            return null;
        }

        Ref master = result.getAdvertisedRef(Constants.R_HEADS + Constants.MASTER);
        ObjectId objectId = master != null ? master.getObjectId() : null;
        if (headId.equals(objectId)) {
            return master;
        }

        Ref foundBranch = null;
        for (Ref r : result.getAdvertisedRefs()) {
            final String n = r.getName();
            if (!n.startsWith(Constants.R_HEADS))
                continue;
            if (headId.equals(r.getObjectId())) {
                foundBranch = r;
                break;
            }
        }
        return foundBranch;
    }

    private void addMergeConfig(Repository clonedRepo, Ref head) throws IOException {
        String branchName = Repository.shortenRefName(head.getName());
        clonedRepo.getConfig().setString(ConfigConstants.CONFIG_BRANCH_SECTION, branchName,
                ConfigConstants.CONFIG_KEY_REMOTE, remote);
        clonedRepo.getConfig().setString(ConfigConstants.CONFIG_BRANCH_SECTION, branchName,
                ConfigConstants.CONFIG_KEY_MERGE, head.getName());
        String autosetupRebase = clonedRepo.getConfig().getString(ConfigConstants.CONFIG_BRANCH_SECTION, null,
                ConfigConstants.CONFIG_KEY_AUTOSETUPREBASE);
        if (ConfigConstants.CONFIG_KEY_ALWAYS.equals(autosetupRebase)
                || ConfigConstants.CONFIG_KEY_REMOTE.equals(autosetupRebase))
            clonedRepo.getConfig().setEnum(ConfigConstants.CONFIG_BRANCH_SECTION, branchName,
                    ConfigConstants.CONFIG_KEY_REBASE, BranchRebaseMode.REBASE);
        clonedRepo.getConfig().save();
    }

    private RevCommit parseCommit(Repository clonedRepo, Ref ref)
            throws MissingObjectException, IncorrectObjectTypeException, IOException {
        final RevCommit commit;
        try (RevWalk rw = new RevWalk(clonedRepo)) {
            commit = rw.parseCommit(ref.getObjectId());
        }
        return commit;
    }

    /**
     * Set the URI to clone from
     *
     * @param uri
     *            the URI to clone from, or {@code null} to unset the URI. The
     *            URI must be set before {@link #call} is called.
     * @return this instance
     */
    public CloneCommand setURI(String uri) {
        this.uri = uri;
        return this;
    }

    /**
     * The optional directory associated with the clone operation. If the
     * directory isn't set, a name associated with the source uri will be used.
     *
     * @see URIish#getHumanishName()
     * @param directory
     *            the directory to clone to, or {@code null} if the directory
     *            name should be taken from the source uri
     * @return this instance
     * @throws java.lang.IllegalStateException
     *             if the combination of directory, gitDir and bare is illegal.
     *             E.g. if for a non-bare repository directory and gitDir point
     *             to the same directory of if for a bare repository both
     *             directory and gitDir are specified
     */
    public CloneCommand setDirectory(File directory) {
        validateDirs(directory, gitDir, bare);
        this.directory = directory;
        return this;
    }

    /**
     * Set the repository meta directory (.git)
     *
     * @param gitDir
     *            the repository meta directory, or {@code null} to choose one
     *            automatically at clone time
     * @return this instance
     * @throws java.lang.IllegalStateException
     *             if the combination of directory, gitDir and bare is illegal.
     *             E.g. if for a non-bare repository directory and gitDir point
     *             to the same directory of if for a bare repository both
     *             directory and gitDir are specified
     * @since 3.6
     */
    public CloneCommand setGitDir(File gitDir) {
        validateDirs(directory, gitDir, bare);
        this.gitDir = gitDir;
        return this;
    }

    /**
     * Set whether the cloned repository shall be bare
     *
     * @param bare
     *            whether the cloned repository is bare or not
     * @return this instance
     * @throws java.lang.IllegalStateException
     *             if the combination of directory, gitDir and bare is illegal.
     *             E.g. if for a non-bare repository directory and gitDir point
     *             to the same directory of if for a bare repository both
     *             directory and gitDir are specified
     */
    public CloneCommand setBare(boolean bare) throws IllegalStateException {
        validateDirs(directory, gitDir, bare);
        this.bare = bare;
        return this;
    }

    /**
     * Set the file system abstraction to be used for repositories created by
     * this command.
     *
     * @param fs
     *            the abstraction.
     * @return {@code this} (for chaining calls).
     * @since 4.10
     */
    public CloneCommand setFs(FS fs) {
        this.fs = fs;
        return this;
    }

    /**
     * The remote name used to keep track of the upstream repository for the
     * clone operation. If no remote name is set, the default value of
     * <code>Constants.DEFAULT_REMOTE_NAME</code> will be used.
     *
     * @see Constants#DEFAULT_REMOTE_NAME
     * @param remote
     *            name that keeps track of the upstream repository.
     *            {@code null} means to use DEFAULT_REMOTE_NAME.
     * @return this instance
     */
    public CloneCommand setRemote(String remote) {
        if (remote == null) {
            remote = Constants.DEFAULT_REMOTE_NAME;
        }
        this.remote = remote;
        return this;
    }

    /**
     * Set the initial branch
     *
     * @param branch
     *            the initial branch to check out when cloning the repository.
     *            Can be specified as ref name (<code>refs/heads/master</code>),
     *            branch name (<code>master</code>) or tag name
     *            (<code>v1.2.3</code>). The default is to use the branch
     *            pointed to by the cloned repository's HEAD and can be
     *            requested by passing {@code null} or <code>HEAD</code>.
     * @return this instance
     */
    public CloneCommand setBranch(String branch) {
        if (branch == null) {
            branch = Constants.HEAD;
        }
        this.branch = branch;
        return this;
    }

    /**
     * The progress monitor associated with the clone operation. By default,
     * this is set to <code>NullProgressMonitor</code>
     *
     * @see NullProgressMonitor
     * @param monitor
     *            a {@link org.eclipse.jgit.lib.ProgressMonitor}
     * @return {@code this}
     */
    public CloneCommand setProgressMonitor(ProgressMonitor monitor) {
        if (monitor == null) {
            monitor = NullProgressMonitor.INSTANCE;
        }
        this.monitor = monitor;
        return this;
    }

    /**
     * Set whether all branches have to be fetched.
     * <p>
     * If {@code false}, use {@link #setBranchesToClone(Collection)} to define
     * what will be cloned. If neither are set, all branches will be cloned.
     * </p>
     *
     * @param cloneAllBranches
     *            {@code true} when all branches have to be fetched (indicates
     *            wildcard in created fetch refspec), {@code false} otherwise.
     * @return {@code this}
     */
    public CloneCommand setCloneAllBranches(boolean cloneAllBranches) {
        this.fetchType = cloneAllBranches ? FETCH_TYPE.ALL_BRANCHES : this.fetchType;
        return this;
    }

    /**
     * Set up a mirror of the source repository. This implies that a bare
     * repository will be created. Compared to {@link #setBare},
     * {@code #setMirror} not only maps local branches of the source to local
     * branches of the target, it maps all refs (including remote-tracking
     * branches, notes etc.) and sets up a refspec configuration such that all
     * these refs are overwritten by a git remote update in the target
     * repository.
     *
     * @param mirror
     *            whether to mirror all refs from the source repository
     *
     * @return {@code this}
     * @since 5.6
     */
    public CloneCommand setMirror(boolean mirror) {
        if (mirror) {
            this.fetchType = FETCH_TYPE.MIRROR;
            setBare(true);
        }
        return this;
    }

    /**
     * Set whether to clone submodules
     *
     * @param cloneSubmodules
     *            true to initialize and update submodules. Ignored when
     *            {@link #setBare(boolean)} is set to true.
     * @return {@code this}
     */
    public CloneCommand setCloneSubmodules(boolean cloneSubmodules) {
        this.cloneSubmodules = cloneSubmodules;
        return this;
    }

    /**
     * Set the branches or tags to clone.
     * <p>
     * This is ignored if {@link #setCloneAllBranches(boolean)
     * setCloneAllBranches(true)} is used. If {@code branchesToClone} is
     * {@code null} or empty, it's also ignored and all branches will be cloned.
     * </p>
     *
     * @param branchesToClone
     *            collection of branches to clone. Must be specified as full ref
     *            names (e.g. {@code refs/heads/master} or
     *            {@code refs/tags/v1.0.0}).
     * @return {@code this}
     */
    public CloneCommand setBranchesToClone(Collection<String> branchesToClone) {
        if (branchesToClone == null || branchesToClone.isEmpty()) {
            // fallback to default
            fetchType = FETCH_TYPE.ALL_BRANCHES;
        } else {
            this.fetchType = FETCH_TYPE.MULTIPLE_BRANCHES;
            this.branchesToClone = branchesToClone;
        }
        return this;
    }

    /**
     * Set whether to skip checking out a branch
     *
     * @param noCheckout
     *            if set to <code>true</code> no branch will be checked out
     *            after the clone. This enhances performance of the clone
     *            command when there is no need for a checked out branch.
     * @return {@code this}
     */
    public CloneCommand setNoCheckout(boolean noCheckout) {
        this.noCheckout = noCheckout;
        return this;
    }

    /**
     * Register a progress callback.
     *
     * @param callback
     *            the callback
     * @return {@code this}
     * @since 4.8
     */
    public CloneCommand setCallback(Callback callback) {
        this.callback = callback;
        return this;
    }

    private static void validateDirs(File directory, File gitDir, boolean bare) throws IllegalStateException {
        if (directory != null) {
            if (directory.exists() && !directory.isDirectory()) {
                throw new IllegalStateException(
                        MessageFormat.format(JGitText.get().initFailedDirIsNoDirectory, directory));
            }
            if (gitDir != null && gitDir.exists() && !gitDir.isDirectory()) {
                throw new IllegalStateException(
                        MessageFormat.format(JGitText.get().initFailedGitDirIsNoDirectory, gitDir));
            }
            if (bare) {
                if (gitDir != null && !gitDir.equals(directory))
                    throw new IllegalStateException(MessageFormat
                            .format(JGitText.get().initFailedBareRepoDifferentDirs, gitDir, directory));
            } else {
                if (gitDir != null && gitDir.equals(directory))
                    throw new IllegalStateException(
                            MessageFormat.format(JGitText.get().initFailedNonBareRepoSameDirs, gitDir, directory));
            }
        }
    }

    private void cleanup() {
        try {
            if (directory != null) {
                if (!directoryExistsInitially) {
                    FileUtils.delete(directory,
                            FileUtils.RECURSIVE | FileUtils.SKIP_MISSING | FileUtils.IGNORE_ERRORS);
                } else {
                    deleteChildren(directory);
                }
            }
            if (gitDir != null) {
                if (!gitDirExistsInitially) {
                    FileUtils.delete(gitDir,
                            FileUtils.RECURSIVE | FileUtils.SKIP_MISSING | FileUtils.IGNORE_ERRORS);
                } else {
                    deleteChildren(gitDir);
                }
            }
        } catch (IOException e) {
            // Ignore; this is a best-effort cleanup in error cases, and
            // IOException should not be raised anyway
        }
    }

    private void deleteChildren(File file) throws IOException {
        File[] files = file.listFiles();
        if (files == null) {
            return;
        }
        for (File child : files) {
            FileUtils.delete(child, FileUtils.RECURSIVE | FileUtils.SKIP_MISSING | FileUtils.IGNORE_ERRORS);
        }
    }
}