oh-my-zsh: add module

modules/default.nix

@@ -24,6 +24,7 @@ let
     ./programs/htop.nix
     ./programs/info.nix
     ./programs/lesspipe.nix
+    ./programs/oh-my-zsh.nix
     ./programs/ssh.nix
     ./programs/texlive.nix
     ./programs/zsh.nix

modules/programs/oh-my-zsh.nix

@@ -0,0 +1,63 @@
+{ config, lib, pkgs, ... }:
+
+with lib;
+
+let
+
+  cfg = config.programs.zsh.oh-my-zsh;
+
+in
+
+{
+  options = {
+    programs.zsh.oh-my-zsh = {
+      enable = mkEnableOption "oh-my-zsh";
+
+      plugins = mkOption {
+        default = [];
+        example = [ "git" "sudo" ];
+        type = types.listOf(types.str);
+        description = ''
+          List of oh-my-zsh plugins
+        '';
+      };
+
+      custom = mkOption {
+        default = "";
+        type = types.str;
+        example = "$HOME/my_customizations";
+        description = ''
+          Path to a custom oh-my-zsh package to override config of oh-my-zsh.
+          See: https://github.com/robbyrussell/oh-my-zsh/wiki/Customization
+        '';
+      };
+
+      theme = mkOption {
+        default = "";
+        example = "robbyrussell";
+        type = types.str;
+        description = ''
+          Name of the theme to be used by oh-my-zsh.
+        '';
+      };
+    };
+  };
+
+  config = mkIf cfg.enable {
+    home.packages = [ pkgs.oh-my-zsh ];
+    programs.zsh.initExtra = with pkgs; ''
+      # oh-my-zsh configuration generated by NixOS
+      export ZSH=${oh-my-zsh}/share/oh-my-zsh
+      ${optionalString (cfg.plugins != [])
+        "plugins=(${concatStringsSep " " cfg.plugins})"
+      }
+      ${optionalString (cfg.custom != "")
+        "ZSH_CUSTOM=\"${cfg.custom}\""
+      }
+      ${optionalString (cfg.theme != "")
+        "ZSH_THEME=\"${cfg.theme}\""
+      }
+      source $ZSH/oh-my-zsh.sh
+    '';
+  };
+}