如何保护金字塔注册表免受测试更改？

Question

I'm trying to write sensible pytest fixtures for testing large pyramid applications.

One of the things I'm trying is to do to speed up test execution is to create the pyramid wsgi app as a session fixture rather than a test fixture , as this creation is reasonably expensive and yet is needed by most tests.

But if any test messes with the app registry in the mean time, the registry will remain polluted for the rest of the test run, and this kind of breakage is difficult to locate as it usually manifests as failures in some random tests in further down the same test run.

So I'd like to be able to either rollback changes to a registry on a fixture teardown or clone a pyramid registry on a fixture set up.

Bonus points if I can lock a registry to raise errors if anyone tries to change a locked down registry.

Question

How do I make sure to always come back to the same pyramid registry while avoiding creating a new wsgi app at every test run?

Answer 1

The registry does not have a supported api for freezing itself. You could subclass it and override some methods to make it readonly-ish if you wanted but it's certainly a bit tedious. Things like setattr, registerUtility, etc.