cpliakas / git-wrapper

     * @throws \GitWrapper\GitException

     *   Thrown when HEAD does not have a remote tracking branch.

     */

    public function isAhead()

    {

        if (!$this->isTracking()) {

            throw new GitException('Error: HEAD does not have a remote tracking branch. Cannot check if it is ahead.');

        }

        $this->clearOutput();

        $merge_base = (string) $this->run(array('merge-base @ @{u}'));

        $local_sha = (string) $this->run(array('rev-parse @'));

        $remote_sha = (string) $this->run(array('rev-parse @{u}'));

        return $merge_base === $remote_sha && $local_sha !== $remote_sha;

    }

    /**

     * Returns whether HEAD is behind its remote tracking branch.

     * @throws \GitWrapper\GitException

     *   Thrown when HEAD does not have a remote tracking branch.

     */

    public function isBehind()

    {

        if (!$this->isTracking()) {

            throw new GitException('Error: HEAD does not have a remote tracking branch. Cannot check if it is behind.');

        }

        $this->clearOutput();

        $merge_base = (string) $this->run(array('merge-base @ @{u}'));

        $local_sha = (string) $this->run(array('rev-parse @'));

        $remote_sha = (string) $this->run(array('rev-parse @{u}'));

        return $merge_base === $local_sha && $local_sha !== $remote_sha;

    }

    /**

     * Returns whether HEAD needs to be merged with its remote tracking branch.

     * @throws \GitWrapper\GitException

     *   Thrown when HEAD does not have a remote tracking branch.

     */

    public function needsMerge()

    {

        if (!$this->isTracking()) {

            throw new GitException('Error: HEAD does not have a remote tracking branch. Cannot check if it is behind.');

        }

        $this->clearOutput();

        $merge_base = (string) $this->run(array('merge-base @ @{u}'));

        $local_sha = (string) $this->run(array('rev-parse @'));

        $remote_sha = (string) $this->run(array('rev-parse @{u}'));

        return $merge_base !== $local_sha && $merge_base !== $remote_sha;

    }

    /**

     * Returns a GitBranches object containing information on the repository's