The test suite sometimes turns off terminal echo after it completes. As far as I can tell, it's completely random and probably caused by tests that don't (or can't!) fully clean up after themselves. After implementing this fix and testing it many times withmake test andmake quicktest, I see a common set of tests that it happens in, but no real rhyme or reason.

This patch just saves and restorestermios.ECHO as a saved test environment and in lots of local testing it works perfectly. Yeah, it's just an annoyance but as#140480 says, this has been annoying me for many releases. Thanks to@zware for suggesting a test environment in my abandoned#140482 PR.

I recommend backporting to all active non-security branches as it will help and there should be no risk involved. One caveat is that I did have to change the signature and semantics oftry_get_module() because if the requested module is not already imported,sys.modules[name] will fail, and sincetermios isn't generally imported,try_get_module() would be unhelpful otherwise. The alternative is to importtermios at the top of the module so it's always available, but as no other saved test environment seems to do that, and this environment is global rather than tied to a specific test, I thought this was the better approach. Suggestions welcome.

• Issue:Test suite sometimes leaves terminal in -echo #140482