zsh: cleanup empty / wrong generated lines

We currently just insert a ton of empty lines when not using certain
options. We also incorrectly generate some notes for options not being
used.

modules/programs/zsh.nix

@@ -627,16 +627,18 @@ in
       programs.zsh.initContent = lib.mkMerge [
         # zprof must be loaded before everything else, since it
         # benchmarks the shell initialization.
-        (mkOrder 400 (optionalString cfg.zprof.enable ''
+        (lib.mkIf cfg.zprof.enable (mkOrder 400 ''
           zmodload zsh/zprof
         ''))
 
-        (mkOrder 550 cfg.initExtraFirst)
+        (lib.mkIf (cfg.initExtraFirst != "") (mkOrder 550 cfg.initExtraFirst))
+
         (mkOrder 600 "typeset -U path cdpath fpath manpath")
 
-        (mkOrder 650 (optionalString (cfg.cdpath != [ ]) ''
+        (lib.mkIf (cfg.cdpath != [ ]) (mkOrder 650 ''
           cdpath+=(${concatStringsSep " " cfg.cdpath})
         ''))
+
         (mkOrder 700 ''
           for profile in ''${(z)NIX_PROFILES}; do
             fpath+=($profile/share/zsh/site-functions $profile/share/zsh/$ZSH_VERSION/functions $profile/share/zsh/vendor-completions)
@@ -645,41 +647,38 @@ in
           HELPDIR="${cfg.package}/share/zsh/$ZSH_VERSION/help"
         '')
 
-        (mkOrder 750 (optionalString (cfg.defaultKeymap != null) ''
+        (lib.mkIf (cfg.defaultKeymap != null) (mkOrder 750 ''
           # Use ${cfg.defaultKeymap} keymap as the default.
           ${lib.getAttr cfg.defaultKeymap bindkeyCommands}
         ''))
 
-        (mkOrder 800 localVarsStr)
+        (lib.mkIf (localVarsStr != "") (mkOrder 800 localVarsStr))
-        (mkOrder 850 cfg.initExtraBeforeCompInit)
 
-        (mkOrder 900 (lib.concatStrings (map (plugin: ''
+        (lib.mkIf (cfg.initExtraBeforeCompInit != "") (mkOrder 850 cfg.initExtraBeforeCompInit))
+
+        (lib.mkIf (cfg.plugins != []) (mkOrder 900 (lib.concatStrings (map (plugin: ''
           path+="$HOME/${pluginsDir}/${plugin.name}"
           fpath+="$HOME/${pluginsDir}/${plugin.name}"
-        '') cfg.plugins)))
+        '') cfg.plugins))))
 
-        (mkOrder 950 ''
+        # NOTE: Oh-My-Zsh/Prezto calls compinit during initialization,
-          # Oh-My-Zsh/Prezto calls compinit during initialization,
+        # calling it twice causes slight start up slowdown
-          # calling it twice causes slight start up slowdown
+        # as all $fpath entries will be traversed again.
-          # as all $fpath entries will be traversed again.
+        (lib.mkIf (cfg.enableCompletion && !cfg.oh-my-zsh.enable && !cfg.prezto.enable)
-          ${optionalString
+          (mkOrder 950 cfg.completionInit))
-          (cfg.enableCompletion && !cfg.oh-my-zsh.enable && !cfg.prezto.enable)
-          cfg.completionInit}'')
 
-        (mkOrder 1000 (optionalString cfg.autosuggestion.enable ''
+        (lib.mkIf cfg.autosuggestion.enable (mkOrder 1000 ''
           source ${pkgs.zsh-autosuggestions}/share/zsh-autosuggestions/zsh-autosuggestions.zsh
           ${optionalString (cfg.autosuggestion.strategy != [ ]) ''
             ZSH_AUTOSUGGEST_STRATEGY=(${
               concatStringsSep " " cfg.autosuggestion.strategy
             })
+          ''}${optionalString (cfg.autosuggestion.highlight != null) ''
+            ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE="${cfg.autosuggestion.highlight}"
           ''}
         ''))
-        (mkOrder 1050 (optionalString
-          (cfg.autosuggestion.enable && cfg.autosuggestion.highlight != null) ''
-            ZSH_AUTOSUGGEST_HIGHLIGHT_STYLE="${cfg.autosuggestion.highlight}"
-          ''))
 
-        (mkOrder 1100 (optionalString cfg.oh-my-zsh.enable ''
+        (lib.mkIf cfg.oh-my-zsh.enable (mkOrder 1100 ''
           # oh-my-zsh extra settings for plugins
           ${cfg.oh-my-zsh.extraConfig}
           # oh-my-zsh configuration generated by NixOS
@@ -691,16 +690,14 @@ in
           ''ZSH_THEME="${cfg.oh-my-zsh.theme}"''}
           source $ZSH/oh-my-zsh.sh
         ''))
-        (mkOrder 1150 ''
-          ${optionalString cfg.prezto.enable (builtins.readFile
-            "${cfg.prezto.package}/share/zsh-prezto/runcoms/zshrc")}
 
-          ${lib.concatStrings (map (plugin: ''
+        (mkOrder 1150 ((optionalString cfg.prezto.enable (builtins.readFile
+          "${cfg.prezto.package}/share/zsh-prezto/runcoms/zshrc"))
+          + (lib.concatStrings (map (plugin: ''
             if [[ -f "$HOME/${pluginsDir}/${plugin.name}/${plugin.file}" ]]; then
               source "$HOME/${pluginsDir}/${plugin.name}/${plugin.file}"
             fi
-          '') cfg.plugins)}
+          '') cfg.plugins)) + ''
-
           # History options should be set in .zshrc and after oh-my-zsh sourcing.
           # See https://github.com/nix-community/home-manager/issues/177.
           HISTSIZE="${toString cfg.history.size}"
@@ -727,21 +724,23 @@ in
           ${if cfg.history.share then "setopt" else "unsetopt"} SHARE_HISTORY
           ${if cfg.history.extended then "setopt" else "unsetopt"} EXTENDED_HISTORY
           ${if cfg.autocd != null then "${if cfg.autocd then "setopt" else "unsetopt"} autocd" else ""}
-        '')
+        ''))
 
-        (mkOrder 1200 cfg.initExtra)
+        (lib.mkIf (cfg.initExtra != "") (mkOrder 1200 cfg.initExtra))
 
-        # Aliases
+        (lib.mkIf (aliasesStr != "" || cfg.shellGlobalAliases != {}) (mkOrder 1250
-        (mkOrder 1250 aliasesStr)
+          ((optionalString (aliasesStr != "") aliasesStr) +
-        (mkOrder 1250 (concatStringsSep "\n" (lib.mapAttrsToList
+           (optionalString (cfg.shellGlobalAliases != {})
-          (k: v: "alias -g -- ${lib.escapeShellArg k}=${lib.escapeShellArg v}")
+             (concatStringsSep "\n" (lib.mapAttrsToList
-          cfg.shellGlobalAliases)))
+               (k: v: "alias -g -- ${lib.escapeShellArg k}=${lib.escapeShellArg v}")
-        (mkOrder 1300 ''
+               cfg.shellGlobalAliases))))))
+
+        (lib.mkIf (dirHashesStr != "") (mkOrder 1300 ''
           # Named Directory Hashes
           ${dirHashesStr}
-        '')
+        ''))
 
-        (mkOrder 1350 (optionalString cfg.syntaxHighlighting.enable
+        (lib.mkIf cfg.syntaxHighlighting.enable (mkOrder 1350
           # Load zsh-syntax-highlighting after all custom widgets have been created
           # https://github.com/zsh-users/zsh-syntax-highlighting#faq
           ''
@@ -759,8 +758,7 @@ in
             )}
           ''))
 
-        (mkOrder 1400 (optionalString
+        (lib.mkIf (cfg.historySubstringSearch.enable or false) (mkOrder 1400
-          (cfg.historySubstringSearch.enable or false)
           # Load zsh-history-substring-search after zsh-syntax-highlighting
           # https://github.com/zsh-users/zsh-history-substring-search#usage
           ''
@@ -773,9 +771,7 @@ in
             (lib.toList cfg.historySubstringSearch.searchDownKey)}
           ''))
 
-        (mkOrder 1450 (optionalString cfg.zprof.enable ''
+        (lib.mkIf cfg.zprof.enable (mkOrder 1450 "zprof"))
-          zprof
-        ''))
       ];
 
       home.file."${relToDotDir ".zshrc"}".text = cfg.initContent;