Problems when use latest version (4.1.0)

[paulocoutinhox]

Hi,

After update my tool to latest pytest, i start getting this error:

https://travis-ci.org/ezored/ezored/jobs/476372726

Can anyone help me?

[RonnyPfannschmidt]

this indicates a broken test which changes to a temporary folder which is subsequently deleted

[RonnyPfannschmidt]

based on https://github.com/ezored/ezored/search?q=chdir&unscoped_q=chdir this seems to be entirely self inflicted as no cleanup seems to happen (at least based on the sample of examples i took a look at

[paulocoutinhox]

Its very strange, since no code was changed, only dependencies updated. Never had this problem.

[nicoddemus]

You say "latest version (2.6.1)", but the latest version is 4.1.0. Was that a typo?

[paulocoutinhox]

Sorry, pytest==4.1.0 and pytest-cov==2.6.1.

[nicoddemus]

Strange that this is only happening now, but @RonnyPfannschmidt's assessment is correct: your test functions change the current directory and this is making coverage to error out when calling os.getcwd.

Search your test code for os.chdir, and replace any calls you find by monkeypatch.chdir instead, which takes care of restoring the original directory. For example (https://github.com/ezored/ezored/blob/master/tests/commands/test_dependency.py#L13):

class TestDependency(TestCase):
    @tempdir()
    def test_dependency_list(self, d):
        os.chdir(d.path)

        d.write(Constants.PROJECT_FILE, Constants.PROJECT_FILE_DATA.encode('utf-8'))
        ...

Becomes:

class TestDependency(TestCase):
    @tempdir()
    def test_dependency_list(self, d, monkeypatch):
        monkeypatch.chdir(d.path)

        d.write(Constants.PROJECT_FILE, Constants.PROJECT_FILE_DATA.encode('utf-8'))
        ...

I was thinking of creating a PR fixing this, but found that there are a ton of files with this pattern (24 files, 50 matches). 😋

[RonnyPfannschmidt]

@nicoddemus he cant use that due to unittest usage

[nicoddemus]

Oh right. Then he will need the "autouse trick" or a custom implementation. I will post those later.

[paulocoutinhox]

If you have any solution, can you post here? It don't happen on old commits:

https://travis-ci.org/ezored/ezored/builds

Very strange.

[blueyed]

Just a sidenote: please take a little more time with reporting, i.e. provide tracebacks as text etc.

[nicoddemus]

Two solutions:

1. Use an autouse fixture to save monkeypatch in self, then use self.monkeypatch on tests:

   class TestDependency(TestCase):
       @pytest.fixture(autouse=True)
       def get_monkeypatch(self, monkeypatch):
           self.monkeypatch = monkeypatch
   
       @tempdir()
       def test_dependency_list(self, d):
           self.monkeypatch.chdir(d.path)
   
           d.write(Constants.PROJECT_FILE, Constants.PROJECT_FILE_DATA.encode('utf-8'))
           ...

2. Implement your own "chdir-like-fixture" that makes use of TestCase.addCleanup to restore cwd to the original directory. This might be the simplest as you can simply do a quick find/replace for the os.chdir calls and add an import:

   # in some utils module somewhere
   def change_cwd(testcase, path):
       old_dir = os.getcwd()
       
       def restore():
           os.chdir(old_dir)
       testcase.addCleanup(restore)
   
       os.chdir(path)
   
   
   # usage
   from .utils import change_cwd
   
   class TestDependency(TestCase):
   
       @tempdir()
       def test_dependency_list(self, d):
           change_cwd(self, d.path)

Hope this helps

[paulocoutinhox]

Hi,

I use the first solution and the problem was solved.

Green again:
https://github.com/ezored/ezored

Thanks.