fish: add module

Signed-off-by: Vincent Demeester <vincent@sbr.pm>

modules/modules.nix

@@ -34,6 +34,7 @@ let
     ./programs/emacs.nix
     ./programs/feh.nix
     ./programs/firefox.nix
+    ./programs/fish.nix
     ./programs/fzf.nix
     ./programs/git.nix
     ./programs/gnome-terminal.nix

modules/programs/fish.nix

@@ -0,0 +1,114 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.programs.fish;
+
+  abbrsStr = concatStringsSep "\n" (
+    mapAttrsToList (k: v: "abbr --add ${k} '${v}'") cfg.shellAbbrs
+  );
+
+  aliasesStr = concatStringsSep "\n" (
+    mapAttrsToList (k: v: "alias ${k}='${v}'") cfg.shellAliases
+  );
+
+in
+
+{
+  options = {
+    programs.fish = {
+      enable = mkEnableOption "fish friendly interactive shell";
+
+      shellAliases = mkOption {
+        default = {};
+        description = ''
+          Set of aliases for fish shell. See <option>environment.shellAliases</option>
+          for an option format description.
+        '';
+        type = types.attrs;
+      };
+      
+      shellAbbrs = mkOption {
+        default = {};
+        description = ''
+          Set of abbreviations for fish shell.
+        '';
+        type = types.attrs;
+      };
+
+      shellInit = mkOption {
+        default = "";
+        description = ''
+          Shell script code called during fish shell initialisation.
+        '';
+        type = types.lines;
+      };
+
+      loginShellInit = mkOption {
+        default = "";
+        description = ''
+          Shell script code called during fish login shell initialisation.
+        '';
+        type = types.lines;
+      };
+
+      interactiveShellInit = mkOption {
+        default = "";
+        description = ''
+          Shell script code called during interactive fish shell initialisation.
+        '';
+        type = types.lines;
+      };
+
+      promptInit = mkOption {
+        default = "";
+        description = ''
+          Shell script code used to initialise fish prompt.
+        '';
+        type = types.lines;
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    home.packages = with pkgs; [ fish ];
+    xdg.configFile."fish/config.fish".text = ''
+      # ~/.config/fish/config.fish: DO NOT EDIT -- this file has been generated automatically.
+      # if we haven't sourced the general config, do it
+      if not set -q __fish_general_config_sourced
+        
+        ${cfg.shellInit}
+        # and leave a note so we don't source this config section again from
+        # this very shell (children will source the general config anew)
+        set -g __fish_general_config_sourced 1
+      end
+      # if we haven't sourced the login config, do it
+      status --is-login; and not set -q __fish_login_config_sourced
+      and begin
+
+        ${cfg.loginShellInit}
+        # and leave a note so we don't source this config section again from
+        # this very shell (children will source the general config anew)
+        set -g __fish_login_config_sourced 1
+      end
+      # if we haven't sourced the interactive config, do it
+      status --is-interactive; and not set -q __fish_interactive_config_sourced
+      and begin    
+        # Abbrs
+        ${abbrsStr}
+  
+        # Aliases
+        ${aliasesStr}
+        
+        ${cfg.promptInit}
+        ${cfg.interactiveShellInit}
+        # and leave a note so we don't source this config section again from
+        # this very shell (children will source the general config anew,
+        # allowing configuration changes in, e.g, aliases, to propagate)
+        set -g __fish_interactive_config_sourced 1
+      end
+    '';
+  };
+}