import jedi
from jedi import common


def test_preload_modules():
    def check_loaded(*modules):
        # + 1 for builtin, +1 for None module (currently used)
        assert len(new) == len(modules) + 2
        for i in modules + ('__builtin__',):
            assert [i in k for k in new.keys() if k is not None]

    from jedi import cache
    temp_cache, cache.parser_cache = cache.parser_cache, {}
    new = cache.parser_cache
    with common.ignored(KeyError): # performance of tests -> no reload
        new['__builtin__'] = temp_cache['__builtin__']

    jedi.preload_module('datetime')
    check_loaded('datetime')
    jedi.preload_module('json', 'token')
    check_loaded('datetime', 'json', 'token')

    cache.parser_cache = temp_cache