I have nothing against integration or end-to-end testing. My problem is the expectation that I can run a test and there wont be side effects or gotchas. I can re-run the test and get the same thing, every single time, and that there is no random chance involved, time of day issues or a possibility that I'll email grandma her receipt again. Integration and e2e tests could be written to avoid those issues too, but not when they're not treated as such.
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