In master, any failing spec raises ExUnit.AssertionError. So any exvcr test that fails will skip clearing the mock, which then breaks all subsequent tests because they're running with another test's cassette.
I just moved your clear code into the after block to resolve, and added a test to verify.
Coverage remained the same at 92.715% when pulling 56ad563ee06b866c378ca22fde3cf882776d3b26 on jeffdeville:ensure_clear_meck_executed into 5c07f3b951ec0fb549fddfae684e1f24164f0dfc on parroty:master.
In master, any failing spec raises ExUnit.AssertionError. So any exvcr test that fails will skip clearing the mock, which then breaks all subsequent tests because they're running with another test's cassette.
I just moved your clear code into the after block to resolve, and added a test to verify.