plugins/haskell-scope-highlighting: init + test

Add warning for Treesitter dependency

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

add test for highlights, add package

tweak warning message

enable treesitter in tests

suggested change

plugins/default.nix

@@ -46,6 +46,7 @@
 
     ./languages/clangd-extensions.nix
     ./languages/debugprint.nix
+    ./languages/haskell-scope-highlighting.nix
     ./languages/julia/julia-cell.nix
     ./languages/lean.nix
     ./languages/ledger.nix
@@ -61,15 +62,15 @@
     ./languages/tagbar.nix
     ./languages/treesitter/hmts.nix
     ./languages/treesitter/rainbow-delimiters.nix
-    ./languages/treesitter/treesitter.nix
     ./languages/treesitter/treesitter-context.nix
     ./languages/treesitter/treesitter-playground.nix
     ./languages/treesitter/treesitter-refactor.nix
     ./languages/treesitter/treesitter-textobjects.nix
+    ./languages/treesitter/treesitter.nix
     ./languages/treesitter/ts-autotag.nix
     ./languages/treesitter/ts-context-commentstring.nix
-    ./languages/typst/typst-vim.nix
     ./languages/typescript-tools.nix
+    ./languages/typst/typst-vim.nix
     ./languages/vim-slime.nix
     ./languages/vimtex.nix
     ./languages/zig.nix

plugins/languages/haskell-scope-highlighting.nix

@@ -0,0 +1,24 @@
+{
+  lib,
+  pkgs,
+  helpers,
+  config,
+  ...
+}:
+with lib; let
+  cfg = config.plugins.haskell-scope-highlighting;
+in {
+  options.plugins.haskell-scope-highlighting = {
+    enable = mkEnableOption "haskell-scope-highlighting";
+
+    package = helpers.mkPackageOption "haskell-scope-highlighting" pkgs.vimPlugins.haskell-scope-highlighting-nvim;
+  };
+
+  config = mkIf cfg.enable {
+    warnings = optional (!config.plugins.treesitter.enable) ''
+      Nixvim (plugins.haskell-scope-highlighting): haskell-scope-highlighting needs treesitter to function as intended. Please, enable it by setting `plugins.treesitter.enable` to `true`.
+    '';
+
+    extraPlugins = [cfg.package];
+  };
+}

tests/test-sources/plugins/languages/haskell-scope-highlighting.nix

@@ -0,0 +1,24 @@
+{
+  empty = {
+    plugins.haskell-scope-highlighting.enable = true;
+    plugins.treesitter.enable = true;
+  };
+
+  testHaskellHighlights = {
+    plugins.haskell-scope-highlighting.enable = true;
+    plugins.treesitter.enable = true;
+    highlight = {
+      HaskellCurrentScope.bg = "black";
+      HaskellParentScope1.bg = "black";
+      HaskellParentScope2.bg = "black";
+      HaskellParentScope3.bg = "black";
+      HaskellVariableDeclarationWithinScope.bg = "black";
+      HaskellVariableDeclaredWithinFile.bg = "black";
+      HaskellVariableDeclaredWithinParent1.bg = "black";
+      HaskellVariableDeclaredWithinParent2.bg = "black";
+      HaskellVariableDeclaredWithinParent3.bg = "black";
+      HaskellVariableDeclaredWithinScope.bg = "black";
+      HaskellVariableNotDeclaredWithinFile.bg = "black";
+    };
+  };
+}