gitmessenger: init plugin (#154)

lib/helpers.nix

@@ -73,6 +73,8 @@ rec {
     description = desc;
   };
 
+  mkIfNonNull = c: mkIf (!isNull c) c;
+
   defaultNullOpts = rec {
     mkNullable = type: default: desc: mkNullOrOption type (
       let

plugins/default.nix

@@ -18,6 +18,7 @@
 
     ./git/fugitive.nix
     ./git/gitgutter.nix
+    ./git/gitmessenger.nix
     ./git/gitsigns.nix
     ./git/neogit.nix
   

plugins/git/gitmessenger.nix

@@ -0,0 +1,117 @@
+{ pkgs
+, lib
+, config
+, ...
+} @ args:
+with lib; let
+  helpers = import ../helpers.nix args;
+in
+{
+  options.plugins.gitmessenger = {
+    enable = mkEnableOption "Enable the gitmessenger plugin";
+
+    package = helpers.mkPackageOption "git-messenger" pkgs.vimPlugins.git-messenger-vim;
+
+    closeOnCursorMoved = helpers.defaultNullOpts.mkBool true ''
+      A popup window is no longer closed automatically when moving a cursor after the window is
+      shown up.
+    '';
+    includeDiff = helpers.defaultNullOpts.mkEnumFirstDefault [ "none" "current" "all" ] ''
+      When this value is not set to "none", a popup window includes diff hunks of the commit at
+      showing up. "current" includes diff hunks of only current file in the commit. "all" includes
+      all diff hunks in the commit.
+
+      Please note that typing d/D or r/R in popup window toggle showing diff hunks even if this
+      value is set to "none".
+    '';
+    gitCommand =
+      helpers.defaultNullOpts.mkStr "git"
+        "git command to retrieve commit messages.";
+    noDefaultMappings =
+      helpers.defaultNullOpts.mkBool false
+        "When this value is set, it does not define any key mappings";
+    intoPopupAfterShow = helpers.defaultNullOpts.mkBool true ''
+      When this value is set to v:false, running :GitMessenger or <plug>(git-messenger) again after
+      showing a popup does not move the cursor in the window.
+    '';
+    alwaysIntoPopup = helpers.defaultNullOpts.mkBool false ''
+      When this value is set to v:true, the cursor goes into a popup window when running
+      :GitMessenger or <Plug>(git-messenger).
+    '';
+    extraBlameArgs = helpers.defaultNullOpts.mkStr "" ''
+      When this variable is set the contents will be appended to the git blame command. Use it to
+      add options (like -w).
+    '';
+    previewMods = helpers.defaultNullOpts.mkStr "" ''
+      This variable is effective only when opening preview window (on Neovim (0.3.0 or earlier)
+      or Vim).
+
+      Command modifiers for opening preview window. The value will be passed as prefix of :pedit
+      command. For example, setting "botright" to the variable opens a preview window at bottom of
+      the current window. Please see :help <mods> for more details.
+    '';
+
+    maxPopupHeight = mkOption {
+      type = types.nullOr types.int;
+      default = null;
+      description = ''
+        Max lines of popup window in an integer value. Setting null means no limit.
+      '';
+    };
+
+    maxPopupWidth = mkOption {
+      type = types.nullOr types.int;
+      default = null;
+      description = ''
+        Max characters of popup window in an integer value. Setting null means no limit.
+      '';
+    };
+
+    dateFormat = helpers.defaultNullOpts.mkStr "%c" ''
+      String value to format dates in popup window. Please see :help strftime() to know the details
+      of the format.
+    '';
+
+    concealWordDiffMarker = helpers.defaultNullOpts.mkBool true ''
+      When this value is set to v:true, markers for word diffs like [-, -], {+, +} are concealed.
+      Set false when you don't want to hide them.
+
+      Note: Word diff is enabled by typing "r" in a popup window.
+    '';
+
+    floatingWinOps = helpers.defaultNullOpts.mkNullable (types.attrsOf types.anything) "{}" ''
+      Options passed to nvim_open_win() on opening a popup window. This is useful when you want to
+      override some window options.
+    '';
+
+    popupContentMargins = helpers.defaultNullOpts.mkBool true ''
+      Setting true means adding margins in popup window. Blank lines at the top and bottom of popup
+      content are inserted. And every line is indented with one whitespace character. Setting false
+      to this variable removes all the margins.
+    '';
+  };
+
+  config =
+    let
+      cfg = config.plugins.gitmessenger;
+    in
+    mkIf cfg.enable {
+      extraPlugins = [ cfg.package ];
+      globals = {
+        git_messenger_close_on_cursor_moved = cfg.closeOnCursorMoved;
+        git_messenger_include_diff = cfg.includeDiff;
+        git_messenger_git_command = cfg.gitCommand;
+        git_messenger_no_default_mappings = cfg.noDefaultMappings;
+        git_messenger_into_popup_after_show = cfg.intoPopupAfterShow;
+        git_messenger_always_into_popup = cfg.alwaysIntoPopup;
+        git_messenger_extra_blame_args = cfg.extraBlameArgs;
+        git_messenger_preview_mods = cfg.previewMods;
+        git_messenger_max_popup_height = cfg.maxPopupHeight;
+        git_messenger_max_popup_width = cfg.maxPopupWidth;
+        git_messenger_date_format = cfg.dateFormat;
+        git_messenger_conceal_word_diff_marker = cfg.concealWordDiffMarker;
+        git_messenger_floating_win_opts = cfg.floatingWinOps;
+        git_messenger_popup_content_margins = cfg.popupContentMargins;
+      };
+    };
+}