From 80ee86a2a81b5f029d5c8a85930cf549f9842635 Mon Sep 17 00:00:00 2001
From: HiPhish <hiphish@posteo.de>
Date: Mon, 15 Jan 2024 23:47:02 +0100
Subject: [PATCH] Avoid reinstalling parser in tests

Uses a custom function in the faker user config.  This function can be
called via RPC in the process under test.
---
 .gitignore                                |  3 ++-
 test/e2e/config.lua                       |  4 ++--
 test/xdg/config/nvim/plugin/ts-ensure.lua | 14 ++++++++++++++
 3 files changed, 18 insertions(+), 3 deletions(-)
 create mode 100644 test/xdg/config/nvim/plugin/ts-ensure.lua

diff --git a/.gitignore b/.gitignore
index a7b6a7d..e3df9c5 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,6 +1,7 @@
 # Tag file created by Vim
 doc/tags
-test/xdg/config/nvim/
+
+# Fake user directory structures
 test/xdg/local/share/nvim/
 test/xdg/local/state/nvim/
 !test/xdg/local/share/nvim/site/pack/testing/start/rainbow-delimiters
diff --git a/test/e2e/config.lua b/test/e2e/config.lua
index 1787dd6..2849514 100644
--- a/test/e2e/config.lua
+++ b/test/e2e/config.lua
@@ -71,7 +71,7 @@ describe('User settings are respected', function()
 			end)
 
 			it('Uses the strategy returned by the thunk', function()
-				request('nvim_command', 'TSInstallSync! lua')
+				request(exec_lua, 'TSEnsure(...)', {'lua'})
 				request(buf_set_lines, 0, 0, -1, true, {'print "Hello world"', '-- vim:ft=lua'})
 				request('nvim_command', 'filetype detect')
 				local attachments = request(exec_lua, 'return the_strategy.attachments[1]', {})
@@ -79,7 +79,7 @@ describe('User settings are respected', function()
 			end)
 
 			it('Does nothing if the thunk returns nil', function()
-				request('nvim_command', 'TSInstallSync! vim')
+				request(exec_lua, 'TSEnsure(...)', {'vim'})
 				request(buf_set_lines, 0, 0, -1, true, {'echo "Hello world"', '" vim:ft=vim'})
 				request('nvim_command', 'filetype detect')
 				local attachments = request(exec_lua, 'return the_strategy.attachments[1]', {})
diff --git a/test/xdg/config/nvim/plugin/ts-ensure.lua b/test/xdg/config/nvim/plugin/ts-ensure.lua
new file mode 100644
index 0000000..8bd783e
--- /dev/null
+++ b/test/xdg/config/nvim/plugin/ts-ensure.lua
@@ -0,0 +1,14 @@
+local get_runtime_file = vim.api.nvim_get_runtime_file
+local parser_pattern = 'parser/%s.*'
+
+---Wrapper around the `:TSinstall` command which will only install a parser if
+---it is not installed yet
+---@param lang string  Language to install
+function TSEnsure(lang, ...)
+	for _, l in ipairs({lang, ...}) do
+		local parsers = get_runtime_file(parser_pattern:format(l), true)
+		if #parsers == 0 then
+			vim.cmd {cmd = 'TSInstallSync', args = {l}}
+		end
+	end
+end