# Compile all `test_cases` cases in one file.
	fun compile do
		# find nitc
		var nitc = toolcontext.find_nitc
		# compile test suite
		var file = test_file
		var module_file = mmodule.location.file
		if module_file == null then
			toolcontext.error(null, "Error: cannot find module file for {mmodule.name}.")
			toolcontext.check_errors
			return
		end
		var include_dir = module_file.filename.dirname
		var cmd = "{nitc} --no-color -q '{file}.nit' -I {include_dir} -o '{file}.bin' > '{file}.out' 2>&1 </dev/null"
		var res = toolcontext.safe_exec(cmd)
		var f = new FileReader.open("{file}.out")
		var msg = f.read_all
		f.close
		if res != 0 then
			failure = msg
		end
	end