wip improve path handling

modules/programs/zsh.nix

@@ -3,29 +3,33 @@
 with lib;
 
 let
+  homeDir = config.home.homeDirectory;
   cfg = config.programs.zsh;
 
-  relToDotDir = file: (optionalString (cfg.dotDir != null) (cfg.dotDir + "/")) + file;
+  dotDirParsed =
+    escapeShellArg (
+      removeSuffix "/" (
+        (optionalString (!hasPrefix "/" cfg.dotDir) homeDir) + "/${cfg.dotDir}"
+      )
+    );
 
-  pluginsDir = if cfg.dotDir != null then
+  dotDirRelToHome = removePrefix "${homeDir}/" dotDirParsed;
-    relToDotDir "plugins" else ".zsh/plugins";
+
+  pluginsDir = dotDirParsed
+    + (optionalString homeDir == dotDirParsed "/.zsh")
+    + "/plugins";
 
   envVarsStr = config.lib.zsh.exportAll cfg.sessionVariables;
   localVarsStr = config.lib.zsh.defineAll cfg.localVariables;
 
   aliasesStr = concatStringsSep "\n" (
-    mapAttrsToList (k: v: "alias -- ${lib.escapeShellArg k}=${lib.escapeShellArg v}") cfg.shellAliases
+    mapAttrsToList (k: v: "alias -- ${escapeShellArg k}=${escapeShellArg v}") cfg.shellAliases
   );
 
   dirHashesStr = concatStringsSep "\n" (
     mapAttrsToList (k: v: ''hash -d ${k}="${v}"'') cfg.dirHashes
   );
 
-  # Absolute paths are assigned unmutated, relative paths
-  # are prepended with the user's home directory.
-  zdotdir = (strings.optionalString (!strings.hasPrefix "/" cfg.dotDir)
-    config.home.homeDirectory) + escapeShellArg cfg.dotDir;
-
   bindkeyCommands = {
     emacs = "bindkey -e";
     viins = "bindkey -v";
@@ -66,14 +70,9 @@ let
 
       path = mkOption {
         type = types.str;
-        default = if versionAtLeast stateVersion "20.03"
+        default = "${dotDirParsed}/.zsh_history";
-          then "$HOME/.zsh_history"
+        defaultText = "`\${config.programs.zsh.dotDir}/.zsh_history`";
-          else relToDotDir ".zsh_history";
+        example = "`\${config.xdg.dataHome}/zsh/zsh_history`";
-        defaultText = literalExpression ''
-          "$HOME/.zsh_history" if state version ≥ 20.03,
-          "$ZDOTDIR/.zsh_history" otherwise
-        '';
-        example = literalExpression ''"''${config.xdg.dataHome}/zsh/zsh_history"'';
         description = "History file location";
       };
 
@@ -183,7 +182,7 @@ let
       custom = mkOption {
         default = "";
         type = types.str;
-        example = "$HOME/my_customizations";
+        example = "\${config.home.homeDirectory}/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>
@@ -307,12 +306,14 @@ in
       };
 
       dotDir = mkOption {
-        default = null;
+        default = homeDir;
-        example = ".config/zsh";
+        defaultText = "`config.home.homeDirectory`";
+        example = "`\${config.xdg.configHome}/zsh`";
         description = ''
-          Directory where the zsh configuration should be located. The default
+          Custom directory for zsh configuration and data. If unset, .zshrc,
-          is the home directory. This option accepts absolute paths, or paths
+          .zshenv and similar are stored in the user's home directory, while
-          relative to `config.home.homeDirectory`.
+          plugins and other data are stored in `.zsh/`. This option accepts
+          absolute paths, or paths relative to the user's home directory.
         '';
         type = types.nullOr types.str;
       };
@@ -351,9 +352,9 @@ in
         default = {};
         example = literalExpression ''
           {
-            docs  = "$HOME/Documents";
+            docs  = "''${config.home.homeDirectory}/Documents";
-            vids  = "$HOME/Videos";
+            vids  = "''${config.home.homeDirectory}/Videos";
-            dl    = "$HOME/Downloads";
+            dl    = "''${config.home.homeDirectory)/Downloads";
           }
         '';
         description = ''
@@ -544,31 +545,31 @@ in
 
   config = mkIf cfg.enable (mkMerge [
     (mkIf (cfg.envExtra != "") {
-      home.file."${relToDotDir ".zshenv"}".text = cfg.envExtra;
+      home.file."${dotDirRelToHome}/.zshenv".text = cfg.envExtra;
     })
 
     (mkIf (cfg.profileExtra != "") {
-      home.file."${relToDotDir ".zprofile"}".text = cfg.profileExtra;
+      home.file."${dotDirRelToHome}/.zprofile".text = cfg.profileExtra;
     })
 
     (mkIf (cfg.loginExtra != "") {
-      home.file."${relToDotDir ".zlogin"}".text = cfg.loginExtra;
+      home.file."${dotDirRelToHome}/.zlogin".text = cfg.loginExtra;
     })
 
     (mkIf (cfg.logoutExtra != "") {
-      home.file."${relToDotDir ".zlogout"}".text = cfg.logoutExtra;
+      home.file."${dotDirRelToHome}/.zlogout".text = cfg.logoutExtra;
     })
 
     (mkIf cfg.oh-my-zsh.enable {
-      home.file."${relToDotDir ".zshenv"}".text = ''
+      home.file."${dotDirRelToHome}/.zshenv".text = ''
         ZSH="${cfg.oh-my-zsh.package}/share/oh-my-zsh";
         ZSH_CACHE_DIR="${config.xdg.cacheHome}/oh-my-zsh";
       '';
     })
 
-    (mkIf (cfg.dotDir != null) {
+    (mkIf (dotDirParsed != homeDir) {
-      home.file."${relToDotDir ".zshenv"}".text = ''
+      home.file."${dotDirRelToHome}/.zshenv".text = ''
-        export ZDOTDIR=${zdotdir}
+        export ZDOTDIR=${dotDirParsed}
       '';
 
       # When dotDir is set, only use ~/.zshenv to source ZDOTDIR/.zshenv,
@@ -576,12 +577,12 @@ in
       # already set correctly (by e.g. spawning a zsh inside a zsh), all env
       # vars still get exported
       home.file.".zshenv".text = ''
-        source ${zdotdir}/.zshenv
+        source ${dotDirParsed}/.zshenv
       '';
     })
 
     {
-      home.file."${relToDotDir ".zshenv"}".text = ''
+      home.file."${dotDirRelToHome}/.zshenv".text = ''
         # Environment variables
         . "${config.home.profileDirectory}/etc/profile.d/hm-session-vars.sh"
 
@@ -598,7 +599,7 @@ in
         ++ optional cfg.enableCompletion pkgs.nix-zsh-completions
         ++ optional cfg.oh-my-zsh.enable cfg.oh-my-zsh.package;
 
-      home.file."${relToDotDir ".zshrc"}".text = concatStringsSep "\n" ([
+      home.file."${dotDirRelToHome}/.zshrc".text = concatStringsSep "\n" ([
         # zprof must be loaded before everything else, since it
         # benchmarks the shell initialization.
         (optionalString cfg.zprof.enable ''
@@ -679,7 +680,7 @@ in
         # See https://github.com/nix-community/home-manager/issues/177.
         HISTSIZE="${toString cfg.history.size}"
         SAVEHIST="${toString cfg.history.save}"
-        ${optionalString (cfg.history.ignorePatterns != []) "HISTORY_IGNORE=${lib.escapeShellArg "(${lib.concatStringsSep "|" cfg.history.ignorePatterns})"}"}
+        ${optionalString (cfg.history.ignorePatterns != []) "HISTORY_IGNORE=${escapeShellArg "(${concatStringsSep "|" cfg.history.ignorePatterns})"}"}
         ${if versionAtLeast config.home.stateVersion "20.03"
           then ''HISTFILE="${cfg.history.path}"''
           else ''HISTFILE="$HOME/${cfg.history.path}"''}
@@ -701,7 +702,7 @@ in
         ${aliasesStr}
         ''
       ]
-      ++ (mapAttrsToList (k: v: "alias -g -- ${lib.escapeShellArg k}=${lib.escapeShellArg v}") cfg.shellGlobalAliases)
+      ++ (mapAttrsToList (k: v: "alias -g -- ${escapeShellArg k}=${escapeShellArg v}") cfg.shellGlobalAliases)
       ++ [ (''
         # Named Directory Hashes
         ${dirHashesStr}
@@ -730,13 +731,13 @@ in
           # https://github.com/zsh-users/zsh-history-substring-search#usage
         ''
           source ${pkgs.zsh-history-substring-search}/share/zsh-history-substring-search/zsh-history-substring-search.zsh
-          ${lib.concatMapStringsSep "\n"
+          ${concatMapStringsSep "\n"
             (upKey: "bindkey \"${upKey}\" history-substring-search-up")
-            (lib.toList cfg.historySubstringSearch.searchUpKey)
+            (toList cfg.historySubstringSearch.searchUpKey)
           }
-          ${lib.concatMapStringsSep "\n"
+          ${concatMapStringsSep "\n"
             (downKey: "bindkey \"${downKey}\" history-substring-search-down")
-            (lib.toList cfg.historySubstringSearch.searchDownKey)
+            (toList cfg.historySubstringSearch.searchDownKey)
           }
         '')