git.py 文件源码

def predictLiveBuildId(self):
        if self.__commit:
            return [ bytes.fromhex(self.__commit) ]

        if self.__tag:
            # Annotated tags are objects themselves. We need the commit object!
            refs = ["refs/tags/" + self.__tag + '^{}', "refs/tags/" + self.__tag]
        else:
            refs = ["refs/heads/" + self.__branch]
        cmdLine = ['git', 'ls-remote', self.__url] + refs
        try:
            output = subprocess.check_output(cmdLine, universal_newlines=True,
                stderr=subprocess.DEVNULL).strip()
        except subprocess.CalledProcessError as e:
            return [None]

        # have we found anything at all?
        if not output:
            return [None]

        # See if we got one of our intended refs. Git is generating lines with
        # the following format:
        #
        #   <sha1>\t<refname>
        #
        # Put the output into a dict with the refname as key. Be extra careful
        # and strip out lines not matching this pattern.
        output = {
            commitAndRef[1].strip() : bytes.fromhex(commitAndRef[0].strip())
            for commitAndRef
            in (line.split('\t') for line in output.split('\n'))
            if len(commitAndRef) == 2 }
        for ref in refs:
            if ref in output: return [output[ref]]

        # uhh, should not happen...
        return [None]