Issue description

On NixOS 19.03

When running the Awesome Window Manager, if it's restarted within the same X session (e.g. by sending a SIGHUP or with the default shortcut Ctrl+Mod4+R), the same --search options are added to the command line.

Example of relevant NixOS configuration:

services.xserver = {
      enable = true;

      displayManager = {
      sddm.enable = true;
     };

      desktopManager = {
            default = "none";
            xterm.enable = true;
     };

      windowManager.awesome.enable = true;
};

Steps to reproduce

1. Login using sddm into an X session that uses the awesome+none
2. Open a terminal and run ps aux | grep awesome | grep --color lgi
3. Observe that lgi is highlighted twice in line with

   nixpkgs/pkgs/applications/window-managers/awesome/default.nix

   Line 51 in 1746dc2

   --add-flags '--search ${lgi}/lib/lua/${lua.luaversion}' \

   nixpkgs/pkgs/applications/window-managers/awesome/default.nix

   Line 52 in 1746dc2

   --add-flags '--search ${lgi}/share/lua/${lua.luaversion}' \

4. Restart awesome, e.g. by pressing Ctrl+Mod4+R
5. Run ps aux | grep awesome | grep --color lgi
6. Observe that the number of times that lgi is highlighted has doubled, i.e. the --search options have been appended to the previous command.

Note that windowManager.awesome.luaModules is not affected, i.e. the --search options for those modules is not re-appended on restarts:

Technical details

NixOS

• system: "x86_64-linux"
• host os: Linux 4.19.36-hardened, NixOS, 19.03.172312.330b9fac600 (Koi)
• multi-user?: yes
• sandbox: yes
• version: nix-env (Nix) 2.2.2
• channels(root): "nixos-19.03.172312.330b9fac600"
• channels(user): "unstable-19.09pre176329.d2602779281"
• nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos

awesome 4.3 (Too long)

• Compiled against Lua 5.2.4 (running with Lua 5.2)
• D-Bus support: ✔
• execinfo support: ✔
• xcb-randr version: 1.6
• LGI version: 0.9.2