Modules/Fish: Add mechanism to load/unload fish environment shells with direnv

home/homemodules/default.nix

@@ -39,6 +39,7 @@
     inputs.nixvim.homeModules.nixvim
     inputs.textfox.homeManagerModules.default
     inputs.walker.homeManagerModules.default
+    inputs.direnv-instant.homeModules.direnv-instant
     # inputs.niri.homeModules.niri # Imported by system module
     # inputs.noctalia.homeModules.default
     # inputs.caelestia.homeManagerModules.default

home/homemodules/fish/default.nix

@@ -87,6 +87,40 @@ in {
           shellInit = ''
             set fish_greeting
             yes | fish_config theme save "system-theme"
+
+            # Because we can't source that in a project flake's shellHook (is POSIX), source it here
+            function __project_shell_reload --on-variable INIT_PROJECT_SHELL
+                # Leaving the environment
+                if not set -q INIT_PROJECT_SHELL; or test -z "$INIT_PROJECT_SHELL"
+                    if test -n "$__last_unload_project_shell"; and test -f "$__last_unload_project_shell"
+                        source "$__last_unload_project_shell"
+                    end
+                    set -e __last_init_project_shell
+                    set -e __last_unload_project_shell
+                    return
+                end
+
+                # Entering or switching environments
+                if test "$INIT_PROJECT_SHELL" != "$__last_init_project_shell"
+                    # Cleanup the previous environment
+                    if test -n "$__last_unload_project_shell"; and test -f "$__last_unload_project_shell"
+                        source "$__last_unload_project_shell"
+                    end
+
+                    # Store into variables to persist until next environment switch in the same shell
+                    set -g __last_init_project_shell "$INIT_PROJECT_SHELL"
+                    if set -q UNLOAD_PROJECT_SHELL; and test -f "$UNLOAD_PROJECT_SHELL"
+                        set -g __last_unload_project_shell "$UNLOAD_PROJECT_SHELL"
+                    else
+                        set -e __last_unload_project_shell
+                    end
+
+                    # Source the new environment
+                    if test -f "$INIT_PROJECT_SHELL"
+                        source "$INIT_PROJECT_SHELL"
+                    end
+                end
+            end
           '';
 
           functions = lib.mergeAttrsList [

home/homemodules/kitty/default.nix

@@ -31,8 +31,8 @@ in {
       settings = lib.mkMerge [
         # Linux config
         (lib.mkIf pkgs.stdenv.isLinux {
-          allow_remote_control = "yes"; # For nnn file preview or nvim scrollback
-          listen_on = "unix:@mykitty";
+          allow_remote_control = true; # For nnn file preview or nvim scrollback
+          listen_on = lib.mkDefault "unix:@mykitty"; # This conflicts with direnv-instant
         })
 
         # Common config

home/homemodules/packages/default.nix

@@ -204,9 +204,19 @@ in {
 
       direnv = {
         enable = true;
+        enableFishIntegration = !config.programs.direnv-instant.enable;
+        silent = true;
         nix-direnv.enable = true;
       };
 
+      # This replaces the normal direnv.enableFishIntegration.
+      # direnv-instant = {
+      #   enable = true;
+      #   enableFishIntegration = true;
+      #   enableKittyIntegration = true;
+      #   settings.use_cache = true;
+      # };
+
       eza = {
         enable = true;
         enableFishIntegration = config.homemodules.fish.enable;