zsh: improve histfile handling

Previously, a stateVersion check for 20.03 determined whether or not the input to
`programs.zsh.history.path` would be prepended with `$HOME`. However, this was not
communicated in the documentation, which stated the version check determined whether
the default histfile location would be in `programs.zsh.dotDir` or
`home.homeDirectory`.

The current change simplifies matters and brings path handling in-line with that of
the preceding work on dotDir path handling. If a relative path is provided, it is
parsed as being relative to `home.homeDirectory`. Both absolute and relative paths
are supported, and are cleaned before being passed to other functions.

Tests have been rewritten for the new logic, with case handling for reusability.

Signed-off-by: Austin Horstman <khaneliman12@gmail.com>

modules/programs/zsh/history.nix

@@ -8,9 +8,8 @@ let
   cfg = config.programs.zsh;
 
   inherit (lib) literalExpression mkOption types;
-  inherit (config.home) stateVersion;
 
-  relToDotDir = file: (lib.optionalString (cfg.dotDir != null) (cfg.dotDir + "/")) + file;
+  inherit (import ./lib.nix { inherit config lib; }) dotDirAbs mkAbsPathStr;
 in
 {
   options =
@@ -49,16 +48,9 @@ in
 
             path = mkOption {
               type = types.str;
-              default =
-                if lib.versionAtLeast stateVersion "20.03" then
-                  "$HOME/.zsh_history"
-                else
-                  relToDotDir ".zsh_history";
-              defaultText = literalExpression ''
-                "$HOME/.zsh_history" if state version ≥ 20.03,
-                "$ZDOTDIR/.zsh_history" otherwise
-              '';
-              example = literalExpression ''"''${config.xdg.dataHome}/zsh/zsh_history"'';
+              default = "${dotDirAbs}/.zsh_history";
+              defaultText = "`\${config.programs.zsh.dotDir}/.zsh_history`";
+              example = "`\${config.xdg.dataHome}/zsh/zsh_history`";
               description = "History file location";
             };
 
@@ -188,12 +180,7 @@ in
         ${lib.optionalString (
           cfg.history.ignorePatterns != [ ]
         ) "HISTORY_IGNORE=${lib.escapeShellArg "(${lib.concatStringsSep "|" cfg.history.ignorePatterns})"}"}
-        ${
-          if lib.versionAtLeast stateVersion "20.03" then
-            ''HISTFILE="${cfg.history.path}"''
-          else
-            ''HISTFILE="$HOME/${cfg.history.path}"''
-        }
+        HISTFILE="${mkAbsPathStr cfg.history.path}"
         mkdir -p "$(dirname "$HISTFILE")"
 
         setopt HIST_FCNTL_LOCK

tests/modules/programs/zsh/aliases.nix

@@ -28,7 +28,7 @@
       HISTSIZE="10000"
       SAVEHIST="10000"
 
-      HISTFILE="$HOME/.zsh_history"
+      HISTFILE="/home/hm-user/.zsh_history"
       mkdir -p "$(dirname "$HISTFILE")"
 
       setopt HIST_FCNTL_LOCK

tests/modules/programs/zsh/default.nix

@@ -5,10 +5,9 @@
   zsh-dotdir-default = import ./dotdir.nix "default";
   zsh-dotdir-relative = import ./dotdir.nix "relative";
   zsh-history-ignore-pattern = ./history-ignore-pattern.nix;
-  zsh-history-path-new-custom = ./history-path-new-custom.nix;
-  zsh-history-path-new-default = ./history-path-new-default.nix;
-  zsh-history-path-old-default = ./history-path-old-default.nix;
-  zsh-history-path-old-custom = ./history-path-old-custom.nix;
+  zsh-history-path-absolute = import ./history-path.nix "absolute";
+  zsh-history-path-default = import ./history-path.nix "default";
+  zsh-history-path-relative = import ./history-path.nix "relative";
   zsh-history-substring-search = ./history-substring-search.nix;
   zsh-plugins = ./plugins.nix;
   zsh-prezto = ./prezto.nix;

tests/modules/programs/zsh/history-path-new-custom.nix

@@ -1,11 +0,0 @@
-{
-  home.stateVersion = "20.03";
-  programs.zsh = {
-    enable = true;
-    history.path = "$HOME/some/directory/zsh_history";
-  };
-
-  nmt.script = ''
-    assertFileRegex home-files/.zshrc '^HISTFILE="$HOME/some/directory/zsh_history"$'
-  '';
-}

tests/modules/programs/zsh/history-path-new-default.nix

@@ -1,9 +0,0 @@
-{
-  home.stateVersion = "20.03";
-  programs.zsh.enable = true;
-
-  nmt.script = ''
-    assertFileRegex home-files/.zshrc \
-      '^HISTFILE="${config.home.homeDirectory}/.zsh_history"$'
-  '';
-}

tests/modules/programs/zsh/history-path-old-custom.nix

@@ -1,12 +0,0 @@
-{
-  home.stateVersion = "19.09";
-  programs.zsh = {
-    enable = true;
-    history.path = "some/directory/zsh_history";
-  };
-
-  nmt.script = ''
-    assertFileRegex home-files/.zshrc \
-      '^HISTFILE="${config.home.homeDirectory}/some/directory/zsh_history"$'
-  '';
-}

tests/modules/programs/zsh/history-path-old-default.nix

@@ -1,9 +0,0 @@
-{
-  home.stateVersion = "19.03";
-  programs.zsh.enable = true;
-
-  nmt.script = ''
-    assertFileRegex home-files/.zshrc \
-      '^HISTFILE="${config.home.homeDirectory}/.zsh_history"$'
-  '';
-}

tests/modules/programs/zsh/history-path.nix

@@ -0,0 +1,41 @@
+case:
+{ config, ... }:
+
+let
+  homeDir = config.home.homeDirectory;
+
+  histfileName = ".zsh_history";
+
+  customHistRelPath = "some/subdir/${histfileName}";
+  customHistAbsPath = "${homeDir}/${customHistRelPath}";
+
+  # default option isn't exposed by submodule so this won't reflect
+  # changes to the the module and may need to be updated in future
+  defaultHistPath = "${homeDir}/${histfileName}";
+
+  testPath =
+    if case == "absolute" then
+      customHistAbsPath
+    else if case == "relative" then
+      customHistRelPath
+    else if case == "default" then
+      defaultHistPath
+    else
+      abort "Test condition not provided";
+
+  expectedPath = if case == "default" then defaultHistPath else customHistAbsPath;
+in
+{
+  config = {
+    programs.zsh = {
+      enable = true;
+      history.path = testPath;
+    };
+
+    test.stubs.zsh = { };
+
+    nmt.script = ''
+      assertFileRegex home-files/.zshrc '^HISTFILE="${expectedPath}"$'
+    '';
+  };
+}

tests/modules/programs/zsh/zshrc-content-priorities.nix

@@ -46,7 +46,7 @@
           HISTSIZE="10000"
           SAVEHIST="10000"
 
-          HISTFILE="$HOME/.zsh_history"
+          HISTFILE="/home/hm-user/.zsh_history"
           mkdir -p "$(dirname "$HISTFILE")"
 
           setopt HIST_FCNTL_LOCK