plugins/telescope.extensions.undo: init + (#654)

* new plugin

* add content

* add content

* Update plugins/telescope/undo.nix

Co-authored-by: Gaétan Lepage <33058747+GaetanLepage@users.noreply.github.com>

* Update plugins/telescope/undo.nix

Co-authored-by: Gaétan Lepage <33058747+GaetanLepage@users.noreply.github.com>

* add test

* Update plugins/telescope/undo.nix

Co-authored-by: Gaétan Lepage <33058747+GaetanLepage@users.noreply.github.com>

* fix per pr comments

* fix per pr comments

* fix per pr comments

---------

Co-authored-by: Haseeb Majid <haseeb.majid@imaginecurve.com>
Co-authored-by: Gaétan Lepage <33058747+GaetanLepage@users.noreply.github.com>

plugins/telescope/default.nix

@@ -15,6 +15,7 @@ in {
     ./fzy-native.nix
     ./media-files.nix
     ./project-nvim.nix
+    ./undo.nix
   ];
 
   # TODO:add support for aditional filetypes. This requires autocommands!

plugins/telescope/undo.nix

@@ -0,0 +1,137 @@
+{
+  pkgs,
+  config,
+  lib,
+  ...
+}:
+with lib; let
+  cfg = config.plugins.telescope.extensions.undo;
+  helpers = import ../helpers.nix {inherit lib;};
+in {
+  options.plugins.telescope.extensions.undo = {
+    enable = mkEnableOption "undo";
+
+    package = helpers.mkPackageOption "telescope extension undo" pkgs.vimPlugins.telescope-undo-nvim;
+
+    useDelta = mkOption {
+      type = types.nullOr types.bool;
+      description = ''
+        When set to true, [delta](https://github.com/dandavison/delta) is used for fancy diffs in the preview section.
+        If set to false, `telescope-undo` will not use `delta` even when available and fall back to a plain diff with
+        treesitter highlights.
+      '';
+      default = true;
+    };
+
+    useCustomCommand = mkOption {
+      type = types.nullOr (types.listOf types.str);
+      description = ''
+        should be in this format: [ "bash" "-c" "echo '$DIFF' | delta" ]
+      '';
+      default = null;
+    };
+
+    sideBySide = mkOption {
+      type = types.nullOr types.bool;
+      description = ''
+        If set to true tells `delta` to render diffs side-by-side. Thus, requires `delta` to be
+        used. Be aware that `delta` always uses its own configuration, so it might be that you're getting
+        the side-by-side view even if this is set to false.
+      '';
+      default = false;
+    };
+
+    diffContextLines = mkOption {
+      type = with types;
+        either ints.unsigned str;
+      description = ''Defaults to the scrolloff'';
+      default = "vim.o.scrolloff";
+    };
+
+    entryFormat = mkOption {
+      type = types.nullOr types.str;
+      description = ''The format to show on telescope for the different versions of the file.'';
+      default = "state #$ID, $STAT, $TIME";
+    };
+
+    timeFormat = mkOption {
+      type = types.nullOr types.str;
+      description = ''
+        Can be set to a [Lua date format string](https://www.lua.org/pil/22.1.html).
+      '';
+      default = "";
+    };
+
+    mappings = {
+      i =
+        helpers.defaultNullOpts.mkNullable
+        (
+          with types;
+            attrsOf str
+        )
+        ''
+          {
+               "<cr>" = "yank_additions";
+               "<s-cr>" = "yank_deletions";
+               "<c-cr>" = "restore";
+          }
+        ''
+        "Keymaps in insert mode";
+      n =
+        helpers.defaultNullOpts.mkNullable
+        (
+          with types;
+            attrsOf str
+        )
+        ''
+           {
+                 "y" = "yank_additions";
+                 "Y" = "yank_deletions";
+                 "u" = "restore";
+          }
+        ''
+        "Keymaps in normal mode";
+    };
+  };
+
+  config = let
+    configuration = with cfg; {
+      use_delta = useDelta;
+      use_custom_command = useCustomCommand;
+      side_by_side = sideBySide;
+      diff_context_lines =
+        if isInt diffContextLines
+        then helpers.mkRaw "diffContextLines"
+        else diffContextLines;
+      entry_format = entryFormat;
+      time_format = timeFormat;
+      mappings = with mappings; {
+        i =
+          helpers.ifNonNull' i
+          (
+            mapAttrs
+            (key: action:
+              helpers.mkRaw "require('telescope-undo.actions').${action}")
+            i
+          );
+
+        n =
+          helpers.ifNonNull' n
+          (
+            mapAttrs
+            (key: action:
+              helpers.mkRaw "require('telescope-undo.actions').${action}")
+            n
+          );
+      };
+    };
+  in
+    mkIf
+    cfg.enable
+    {
+      extraPlugins = [cfg.package];
+
+      plugins.telescope.enabledExtensions = ["undo"];
+      plugins.telescope.extensionConfig."undo" = configuration;
+    };
+}

tests/test-sources/plugins/telescope/undo.nix

@@ -0,0 +1,34 @@
+{
+  empty = {
+    plugins.telescope.enable = true;
+  };
+
+  example = {
+    plugins.telescope = {
+      enable = true;
+
+      extensions.undo = {
+        enable = true;
+
+        useDelta = true;
+        useCustomCommand = ["bash" "-c" "echo '$DIFF' | delta"];
+        sideBySide = true;
+        diffContextLines = 8;
+        entryFormat = "state #$ID";
+        timeFormat = "!%Y-%m-%dT%TZ";
+        mappings = {
+          i = {
+            "<cr>" = "yank_additions";
+            "<s-cr>" = "yank_deletions";
+            "<c-cr>" = "restore";
+          };
+          n = {
+            "y" = "yank_additions";
+            "Y" = "yank_deletions";
+            "u" = "restore";
+          };
+        };
+      };
+    };
+  };
+}