public async Task GitPullFromRepositoryAsync(string repositoryPath, string localDir, string branch, CancellationToken cancel = default)
    {
        string gitUrl = this.Settings.GitLabBaseUrl._CombineUrl(repositoryPath + ".git").ToString();

        gitUrl = gitUrl._ReplaceStr("https://", $"https://*****:*****@");

        await Lfs.CreateDirectoryAsync(localDir);

        // localDir ディレクトリに .git ディレクトリは存在するか?
        string dotgitDir = localDir._CombinePath(".git");

        bool init = false;

        StrDictionary <string> envVars = new StrDictionary <string>();

        // empty config
        string emptyCfgPath = Env.MyLocalTempDir._CombinePath("empty.txt");

        using (await Lock1.LockWithAwait(cancel))
        {
            if (await Lfs.IsFileExistsAsync(emptyCfgPath, cancel) == false)
            {
                await Lfs.WriteStringToFileAsync(emptyCfgPath, "\n\n", cancel : cancel);
            }
        }

        envVars.Add("GIT_CONFIG_GLOBAL", emptyCfgPath);
        envVars.Add("GIT_CONFIG_SYSTEM", emptyCfgPath);

        if (await Lfs.IsDirectoryExistsAsync(dotgitDir, cancel))
        {
            try
            {
                // update を試みる
                await EasyExec.ExecAsync(this.GitExe, $"pull origin {branch}", localDir, cancel : cancel, additionalEnvVars : envVars);
            }
            catch (Exception ex)
            {
                ex._Error();
                init = true;
            }
        }
        else
        {
            init = true;
        }

        if (init)
        {
            // 初期化する
            await Lfs.DeleteDirectoryAsync(localDir, true, cancel : cancel, forcefulUseInternalRecursiveDelete : true);

            // git clone をする
            await EasyExec.ExecAsync(this.GitExe, $"clone {gitUrl} {localDir}", cancel : cancel, additionalEnvVars : envVars);

            // update を試みる
            await EasyExec.ExecAsync(this.GitExe, $"pull origin {branch}", localDir, cancel : cancel, additionalEnvVars : envVars);
        }
    }