Add test for ts syn skip cases

lua/treesitter-matchup/internal.lua

@@ -333,7 +333,7 @@ function M.attach(bufnr, lang)
   local config = configs.get_module('matchup')
 
   if opt_tbl_for_lang(config.additional_vim_regex_highlighting, lang)
-      and api.nvim_buf_set_option(bufnr, 'syntax') == '' then
+      and api.nvim_buf_get_option(bufnr, 'syntax') == '' then
     api.nvim_buf_set_option(bufnr, 'syntax', 'ON')
   end
 

test/new/test-syn/Makefile

@@ -0,0 +1,11 @@
+.PHONY: test
+
+MYVIM ?= nvim --headless
+
+INMAKE := 1
+export INMAKE
+
+test:
+	@MODE=0 $(MYVIM) -u test.vim
+	@MODE=1 $(MYVIM) -u test.vim
+	@MODE=2 $(MYVIM) -u test.vim

test/new/test-syn/example.rb

@@ -0,0 +1,7 @@
+describe '#foo' do
+  context 'when foo' do
+    it 'bars' do
+     expect(1).to eq(1)
+    end
+  end
+end

test/new/test-syn/test.vim

@@ -0,0 +1,40 @@
+set nocompatible
+source ../common/bootstrap.vim
+
+if !$TESTS_ENABLE_TREESITTER && $MODE > 0
+  call matchup#test#finished()
+endif
+
+if $MODE == 1
+  lua <<EOF
+  require'nvim-treesitter.configs'.setup {
+    highlight = { enable = true },
+    matchup   = { enable = true }
+  }
+EOF
+elseif $MODE == 2
+  lua <<EOF
+  require'nvim-treesitter.configs'.setup {
+    highlight = { enable = true },
+    matchup   = {
+      enable = true,
+      additional_vim_regex_highlighting = true
+    }
+  }
+EOF
+endif
+
+silent edit example.rb
+
+function! s:match_test(pos, check) abort
+  call matchup#pos#set_cursor(a:pos)
+  normal %
+  let l:curpos = matchup#pos#get_cursor()[1:2]
+  call matchup#test#assert_equal(a:check, l:curpos)
+endfunction
+
+call s:match_test([7, 1], [1, 17])
+call s:match_test([6, 3], [2, 22])
+call s:match_test([5, 5], [3, 15])
+
+call matchup#test#finished()