git.py 文件源码

def obtain(self, dest):
        url, rev = self.get_url_rev()
        if rev:
            rev_options = [rev]
            rev_display = ' (to %s)' % rev
        else:
            rev_options = ['origin/master']
            rev_display = ''
        if self.check_destination(dest, url, rev_options, rev_display):
            logger.info(
                'Cloning %s%s to %s', url, rev_display, display_path(dest),
            )
            self.run_command(['clone', '-q', url, dest])

            if rev:
                rev_options = self.check_rev_options(rev, dest, rev_options)
                # Only do a checkout if rev_options differs from HEAD
                if not self.check_version(dest, rev_options):
                    self.run_command(
                        ['checkout', '-q'] + rev_options,
                        cwd=dest,
                    )
            #: repo may contain submodules
            self.update_submodules(dest)