This one require a few dependencies at runtime which needs fixing:

• Needs typelib from vte, so needs something similar to eg. this but for vte

  nixpkgs/pkgs/desktops/gnome-3/core/gnome-shell-extensions/default.nix

  Lines 20 to 25 in 373f59f

  	patches = [
  	(substituteAll {
  	src = ./fix_gmenu.patch;
  	gmenu_path = "${gnome-menus}/lib/girepository-1.0";
  	})
  	];

• It runs stuff with gjs so that needs an absolute path, so similar to eg. this:

  nixpkgs/pkgs/applications/backup/deja-dup/fix-paths.patch

  Lines 7 to 8 in 373f59f

  	- Posix.system("/bin/rm -f " + Shell.quote(cache_dir) + "/*/lockfile.lock");
  	+ Posix.system("@coreutils@/bin/rm -f " + Shell.quote(cache_dir) + "/*/lockfile.lock");

@hedning
I dont know how I can perform this changes. For the first one, Do I need to create a patch for my pkg and in this other pkg, somehow download and install this typelib from vte?

And for the second, I should change in the instalPhase to use absolutePath right? I tried to use inside the installPhase Posix.system("@coreutils@/bin/mkdir -p $out/share/gnome-shell/extensions"); but is not working :/

Ah, right, I only meant that the fixes needed here are the same kind of fixes that I referenced.

So the patch will look something like this:

modified   drop-down-terminal@gs-extensions.zzrough.org/extension.js
@@ -15,6 +15,8 @@
 
 // Author: Stéphane Démurget <stephane.demurget@free.fr>
 
+imports.gi.GIRepository.Repository.prepend_search_path('@vte@/lib/lib/girepository-1.0')
+
 const Lang = imports.lang;
 const Gettext = imports.gettext.domain("drop-down-terminal");
 const Mainloop = imports.mainloop;
@@ -653,7 +655,7 @@ const DropDownTerminalExtension = new Lang.Class({
         this._killingChild = false;
 
         // finds the forking arguments
-        let args = ["gjs", GLib.build_filenamev([Me.path, "terminal.js"]), Me.path];
+        let args = ["@gjs@/bin/gjs", GLib.build_filenamev([Me.path, "terminal.js"]), Me.path];
 
         // forks the process
         debug("forking '" + args.join(" ") + "'");

And then @vte@ and @gjs@ just needs to be replaced with the correct paths when building. We have a convenient utility for this. This will find occurrences of the names to the left surrounded with @ and replace them with the expression to the right. So in nix eg. the package vte simply expands to its nix store path when used as a string (This can be seen in action using nix eval nixpkgs.vte --raw):

patches = [
  (substituteAll {
    src = ./fix_paths.patch;
    vte = vte;
    gjs = gnome3.gjs;
  }

Does that make sense?

@hedning
Yep, makes total sense, I'm new to this nix world, but I think I got it how this works now.
I created the patch with the diff, let me know if something is missing.

One question, how do you test this and know that some libs needs absolutePath? I'm just running nix-build -A 'gnomeExtensions.drop-down-terminal' to check if everything its alright

Right, you basically need to run things and see if they work. For regular programs that's usually as simple as result/bin/program.

In the case of gnome-shell extensions we need to run gnome-shell and activate the extension. Doing this in your current gnome-shell can be a bit annoying. To solve that there's two options:

• run a virtual machine
• run a nested gnome-shell session

Building a virtual machine can be very useful in general. Put something like into vm.nix in your nixpkgs repo:

{ pkgs, config, ... }:
{
  environment.systemPackages = with pkgs; [
    gnomeExtensions.drop-down-terminal
  ];

  services.openssh.enable = true;
  boot.cleanTmpDir = true;

  services.xserver = {
    enable = true;

    desktopManager = {
      gnome3.enable = true;
      gnome3.debug = true;
    };

    displayManager = {
      gdm.enable = true;
      gdm.debug = true;
    };
  };

  users.users.foo = {
    isNormalUser = true;
    uid = 1000;
    password = "foobar";
    extraGroups = [ "wheel" "networkmanager" ];
    openssh.authorizedKeys.keys = [
      # put your machines public key here to get ssh access
    ];
  };

  system.stateVersion = "16.09";
}

And then build and run the VM like this for instance:

nixos-rebuild build-vm -I nixpkgs=./. -I nixos-config=./vm.nix
QEMU_NET_OPTS="hostfwd=tcp::2222-:22" ./result/bin/run-*-vm -m 2500

Then you can log in and activate the extension with gnome-tweaks.

Now that takes a while. I use this script through emacs (session.sh) to easily launch nested gnome-shells to test and develop extensions. For that something like this should work:

nix build -f. gnomeExtensions.drop-down-terminal
session.sh wayland result/share/gnome-shell/extensions/drop-down-terminal@gs-extensions.zzrough.org/ drop-down-terminal@gs-extensions.zzrough.org

Uow, its a great way to test, I'll try to setup this and test this whole thing, thank you!

I fixed the vte path, but this time, ther is no error message, so i cannot figure out what is wrong...

When I activate the extension, only this message shows:

And on Looking-glass, there's no error message:

Right, looks like terminal.js also needs the imports.gi.GIRepository.Repository.prepend_search_path('@vte@/lib/girepository-1.0') preamble, as it's run in a separate process.

Finally worked!
Thank you for the incredible help and teach @hedning :)

@ericdallo It appears you're trying to merge this into release-19.03 and all contributions should go to master first. You probably want this in the current stable release, so we can backport it after it's merged to master.

hum, makes sense @worldofpeace , so i need to open the PR to the master, right?

@ericdallo Likely, it's the easiest route. It also appears you're working directly on the release-19.03 branch and not a feature one.

Best to do

git checkout upstream/master
git checkout -b some-branch-name

Got it, I'll create a branch from updated master, open a new PR with theese changes and link it here. Thank you @worldofpeace

Right and squash everything into one commit :)

New PR with commits squashed #70042