fish: support flexible abbreviations

https://github.com/fish-shell/fish-shell/releases/tag/3.6.0

modules/programs/fish.nix

@@ -138,9 +138,76 @@ let
     };
   };
 
-  abbrsStr = concatStringsSep "\n"
-    (mapAttrsToList (k: v: "abbr --add --global -- ${k} ${escapeShellArg v}")
-      cfg.shellAbbrs);
+  abbrModule = types.submodule {
+    options = {
+      expansion = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        description = ''
+          The command expanded by an abbreviation.
+        '';
+      };
+
+      position = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        example = "anywhere";
+        description = ''
+          If the position is "command", the abbreviation expands only if
+          the position is a command. If it is "anywhere", the abbreviation
+          expands anywhere.
+        '';
+      };
+
+      regex = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        description = ''
+          The regular expression pattern matched instead of the literal name.
+        '';
+      };
+
+      setCursor = mkOption {
+        type = with types; (either bool str);
+        default = false;
+        description = ''
+          The marker indicates the position of the cursor when the abbreviation
+          is expanded. When setCursor is true, the marker is set with a default
+          value of "%".
+        '';
+      };
+
+      function = mkOption {
+        type = with types; nullOr str;
+        default = null;
+        description = ''
+          The fish function expanded instead of a literal string.
+        '';
+      };
+    };
+  };
+
+  abbrsStr = concatStringsSep "\n" (mapAttrsToList (name: def:
+    let
+      mods = with def;
+        cli.toGNUCommandLineShell {
+          mkOption = k: v:
+            if v == null then
+              [ ]
+            else if k == "set-cursor" then
+              [ "--${k}=${lib.generators.mkValueStringDefault { } v}" ]
+            else [
+              "--${k}"
+              (lib.generators.mkValueStringDefault { } v)
+            ];
+        } {
+          inherit position regex function;
+          set-cursor = setCursor;
+        };
+      modifiers = if isAttrs def then mods else "";
+      expansion = if isAttrs def then def.expansion else def;
+    in "abbr --add ${modifiers} -- ${name}"
+    + optionalString (expansion != null) " \"${expansion}\"") cfg.shellAbbrs);
 
   aliasesStr = concatStringsSep "\n"
     (mapAttrsToList (k: v: "alias ${k} ${escapeShellArg v}") cfg.shellAliases);
@@ -199,12 +266,18 @@ in {
       };
 
       shellAbbrs = mkOption {
-        type = with types; attrsOf str;
+        type = with types; attrsOf (either str abbrModule);
         default = { };
-        example = {
-          l = "less";
-          gco = "git checkout";
-        };
+        example = literalExpression ''
+          {
+            l = "less";
+            gco = "git checkout";
+            "-C" = {
+              position = "anywhere";
+              expansion = "--color";
+            };
+          }
+        '';
         description = ''
           An attribute set that maps aliases (the top level attribute names
           in this option) to abbreviations. Abbreviations are expanded with