Handle insufficient neovim-versions.

lua/luasnip/extras/treesitter_postfix.lua

@@ -1,3 +1,9 @@
+if vim.version().major == 0 and vim.version().minor < 9 then
+	-- need LanguageTree:tree_for_range and don't want to go through the hassle
+	-- of differentiating multiple version of query.get/parse.
+	error("treesitter_postfix does not support neovim < 0.9")
+end
+
 local snip = require("luasnip.nodes.snippet").S
 local ts = require("luasnip.extras._treesitter")
 local node_util = require("luasnip.nodes.util")

tests/integration/treesitter_postfix_spec.lua

@@ -25,6 +25,12 @@ describe("treesitter-postfix", function()
 
 	for _, reparse_mode in ipairs({[["live"]], [["copy"]], [[nil]]}) do
 		it(("Default-case works [%s]"):format(reparse_mode), function()
+			-- don't run these tests for earlier nvim-versions.
+			if exec_lua([[return vim.version().major == 0 and vim.version().minor < 9]]) then
+				print("Skipping Test due to insufficient version.")
+				return
+			end
+
 			ls_helpers.session_setup_luasnip({
 				setup_parsers = true,
 			})