How is filter_dir supposed to work?

[HiPhish]

Hi,

I'm writing a new adapter and I don't understand how filter_dir is supposed to work. It accepts three arguments: name, rel_path and root. The root parameter is clear: it's the absolute path to the result of calling the adapter's root function; normally the root of the project.

What about the other two? Supposed I have a Lua project that uses busted, then I have a .busted file at the top of the project directory. This will be my root. Now supposed I want to split my tests into unit tests and integration tests. The .busted file would look like this:

return {
	_all = {
		coverage = false,
		lua = './test/nvim-shim'
	},
	default = {
		verbose = true,
	},
	unit = {
		ROOT = {'./test/unit/'},
	},
	integration = {
		ROOT = {'./test/integration/'},
		pattern = '',  -- No fancy pattern for integration tests
	},
}

This means any directory under and including test/unit and test/integration is a test directory, but a directory like test/data or lua is not. Suppose I wanted to filter test/unit/herp/derp, what would be the name and what would be the rel_path? What would be the name and rel_path of test alone? What about other directories like lua or doc?