treesitter: remove foldByDefault

docs/manual/release-notes/rl-0.9.md

@@ -29,6 +29,10 @@
   is unlikely to cause any noticeable change in behavior or breakage, it's
   mentioned just in case.
 
+- `vim.treesitter.foldByDefault` is removed. Folding behavior should be
+  controlled via `vim.options.foldenable` directly instead. RIP
+  `vim.treesitter.foldByDefault` 2026-03-19 - 2026-03-19.
+
 [Snoweuph](https://github.com/snoweuph)
 
 - "Correct `languages.go.treesitter` to contain all Go file types.

modules/extra/deprecations.nix

@@ -342,5 +342,10 @@ in {
         Incremental selection configuration has been removed from nvim-treesitter.
       '')
     ]
+
+    # 2026-03-19
+    [
+      (mkRenamedOptionModule ["vim" "treesitter" "foldByDefault"] ["vim" "options" "foldenable"])
+    ]
   ];
 }

modules/plugins/treesitter/config.nix

@@ -6,7 +6,6 @@
   inherit (lib.modules) mkIf;
   inherit (lib.lists) optionals;
   inherit (lib.nvim.dag) entryAfter;
-  inherit (lib.trivial) boolToString;
 
   cfg = config.vim.treesitter;
 in {
@@ -55,7 +54,6 @@ in {
             callback = function()
               vim.wo[0][0].foldmethod = "expr"
               vim.wo[0][0].foldexpr = "v:lua.vim.treesitter.foldexpr()"
-              vim.o.foldenable = ${boolToString cfg.foldByDefault}
             end,
           })
         ''}

modules/plugins/treesitter/treesitter.nix

@@ -10,7 +10,6 @@ in {
     enable = mkEnableOption "treesitter, also enabled automatically through language options";
 
     fold = mkEnableOption "fold with treesitter";
-    foldByDefault = mkEnableOption "folding by default when a file is opened";
     autotagHtml = mkEnableOption "autoclose and rename html tag";
 
     grammars = mkOption {