Merge pull request #13648 from teto/fix-fold-hl

adds a test to check syntax is taken into account in open folds

contrib/flake.nix

@@ -44,7 +44,7 @@
         pythonEnv = legacyPkgs.python3;
         luacheck = legacyPkgs.luaPackages.luacheck;
       in
-        neovim-debug.overrideAttrs(oa: {
+        (neovim-debug.override({doCheck = true;})).overrideAttrs(oa: {
           cmakeFlags = oa.cmakeFlags ++ [
             "-DLUACHECK_PRG=${luacheck}/bin/luacheck"
             "-DMIN_LOG_LEVEL=0"

test/functional/ui/searchhl_spec.lua

@@ -480,6 +480,11 @@ describe('search highlighting', function()
       {4:search hit BOTTOM, continuing at TOP}    |
     ]])
 
+    -- check hilights work also in folds
+    feed("zf4j")
+    command("%foldopen")
+    screen:expect_unchanged()
+
     feed_command("call clearmatches()")
     screen:expect([[
         very spec{2:^ial te}xt                     |