build: added plenary test runner

.gitignore

@@ -1 +1,3 @@
 tt.lua
+.tests
+doc/tags

tests/init.lua

@@ -0,0 +1,32 @@
+local M = {}
+
+function M.root(root)
+  local f = debug.getinfo(1, "S").source:sub(2)
+  return vim.fn.fnamemodify(f, ":p:h:h") .. "/" .. (root or "")
+end
+
+---@param plugin string
+function M.load(plugin)
+  local name = plugin:match(".*/(.*)")
+  local package_root = M.root(".tests/site/pack/deps/start/")
+  if not vim.loop.fs_stat(package_root .. name) then
+    print("Installing " .. plugin)
+    vim.fn.mkdir(package_root, "p")
+    vim.fn.system({
+      "git",
+      "clone",
+      "--depth=1",
+      "https://github.com/" .. plugin .. ".git",
+      package_root .. "/" .. name,
+    })
+  end
+end
+
+function M.setup()
+  vim.cmd([[set runtimepath=$VIMRUNTIME]])
+  vim.opt.runtimepath:append(M.root())
+  vim.opt.packpath = { M.root(".tests/site") }
+  M.load("nvim-lua/plenary.nvim")
+end
+
+M.setup()

tests/run

@@ -0,0 +1,3 @@
+#!/bin/sh
+
+nvim --headless -u tests/init.lua -c "PlenaryBustedDirectory tests/ {minimal_init = 'tests/init.lua', sequential = true}"