django - 使用模拟测试 django-admin 命令

Question

I have a command (let's call it do_thing ):

class Command(BaseCommand):
    def add_arguments(self, parser):
        parser.add_argument("filename", type=str)

    def handle(self, *args, **kwargs):
        with open(kwargs["filename"]) as f:
            # do something with the data here

and I want to use unittest.mock.mock_open() to simulate reading from a file.

Based off the example shown in the link above, I currently have (in a test in tests.py ):

with patch('__main__.open', mock_open(read_data="some content here")) as m:
        call_command("do_thing", "foo.txt")

However, when I run this, Django/Python acts as if the mock patch had no effect:

FileNotFoundError: [Errno 2] No such file or directory: 'foo.txt'

What am I doing wrong here? Thank you!

Answer 1

I assume the module that has Command class is do_thing . so instead of __main__ which works when you directly execute the module, use that exact module name do_thing

with patch('do_thing.open', mock_open(read_data="some content here")) as m:
    call_command("do_thing", "foo.txt", run=True)