问个 nginx 配置问题

抄来的 nginx 配置，第 1 个 location 的正则表达式不太确定是否正确。按照 AI 的解答，用于匹配下面这几种路径。实测下来，http git clone 也是失败的，未匹配第 1 个 location 。有几个疑点：

1. 类似这种多行的正则，每一行之间是什么关系？按照 AI 的解答看上去是或的关系，但是没找到正则规则的依据。
2. 每一行正则结尾是 空格 + 单引号，这个不知道又是什么规则？

• /git/xxx/HEAD （获取仓库的 HEAD 文件）
• /git/xxx/info/refs （获取仓库引用信息）
• /git/xxx/objects/...（处理 Git 对象）
• /git/xxx/git-upload-pack

location ~ "(?x)^/git(?<path>/.*/(?:HEAD '
                             info/refs '
                             objects/(?:info/[^/]+ '
                                        [0-9a-f]{2}/[0-9a-f]{38} '
                                        pack/pack-[0-9a-f]{40}\.(?:pack '
                                                                   idx)) '
                             git-upload-pack))$" {
        error_page 491 = @auth;
        if ($query_string = service=git-receive-pack) {
                return 491;
        }
        client_max_body_size                    0;

        fastcgi_param   SCRIPT_FILENAME         /usr/lib/git-core/git-http-backend;
        include         fastcgi_params;
        fastcgi_param   GIT_HTTP_EXPORT_ALL     "";
        fastcgi_param   GIT_PROJECT_ROOT        /srv/git;
        fastcgi_param   PATH_INFO               $path;

        fastcgi_param   REMOTE_USER             $remote_user;
        fastcgi_pass    unix:/var/run/fcgiwrap.socket;
}
location ~ "^/git(?<path>/.*/git-receive-pack)$" {
        error_page 491 = @auth;
        return 491;
}
location @auth {
        auth_basic            "Git write access";
        auth_basic_user_file  /srv/git/.htpasswd;

        client_max_body_size                    0;

        fastcgi_param   SCRIPT_FILENAME         /usr/lib/git-core/git-http-backend;
        include         fastcgi_params;
        fastcgi_param   GIT_HTTP_EXPORT_ALL     "";
        fastcgi_param   GIT_PROJECT_ROOT        /srv/git;
        fastcgi_param   PATH_INFO               $path;

        fastcgi_param   REMOTE_USER             $remote_user;
        fastcgi_pass    unix:/var/run/fcgiwrap.socket;
}
location ~ ^/git(?<path>/.*)$ {
        alias /usr/share/cgit;
        try_files $1 @cgit;
}
location @cgit {
        include         fastcgi_params;
        fastcgi_param   SCRIPT_FILENAME /usr/lib/cgit/cgit.cgi;
        fastcgi_param   PATH_INFO       $path;
        fastcgi_param   QUERY_STRING    $args;
        fastcgi_param   HTTP_HOST       $server_name;

        fastcgi_param   CGIT_CONFIG     /srv/git/.cgitrc;

        fastcgi_pass    unix:/var/run/fcgiwrap.socket;
}