That's easier said than done. Simple example: API that returns a count of all users in the database. The obvious correct implementation that will work would be just to `select count(*) from users`. But if some other test touches users table beforehand, it won't work. There is no uuid to latch onto here.
That’s why you run each test in a transaction with proper isolation level, and don’t commit the transaction— roll it back when the test ends. No test ever interferes with another that way.
Frankly this is the better solution for async tests. If the app can handle multiple users interacting with it simultaneously, then it can handle multiple tests. If it can’t, then the dev has bigger problems.
As for assertions, it’s not that hard to think of a better way to check if you made an insertion or not into the db without writing “assert user_count() == 0”
I don’t disagree with you, but there are diminishing returns on making your test suite complex. To make async test work properly, you need to know what you’re doing in regards to message passing, OTP, mocks, shared memory, blah blah blah. It can get really complicated, and it is still isn’t a substitute for real user traffic. You’re going to have to rely on hiring experienced Elixir developers (small talent pool), allow for long onboarding time (expensive), or provide extensive training (difficult). Personally for most cases, writing a sync test suite and just optimizing to keep it not to slow is probably more practical in the long term.
> Just make every test independent
That's easier said than done. Simple example: API that returns a count of all users in the database. The obvious correct implementation that will work would be just to `select count(*) from users`. But if some other test touches users table beforehand, it won't work. There is no uuid to latch onto here.
That’s why you run each test in a transaction with proper isolation level, and don’t commit the transaction— roll it back when the test ends. No test ever interferes with another that way.
yes, Now this test also has to check that your redis-based cache is populated correctly. And/or sends stuff down your RabbitMQ/Kafka pipeline.
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Frankly this is the better solution for async tests. If the app can handle multiple users interacting with it simultaneously, then it can handle multiple tests. If it can’t, then the dev has bigger problems.
As for assertions, it’s not that hard to think of a better way to check if you made an insertion or not into the db without writing “assert user_count() == 0”
I don’t disagree with you, but there are diminishing returns on making your test suite complex. To make async test work properly, you need to know what you’re doing in regards to message passing, OTP, mocks, shared memory, blah blah blah. It can get really complicated, and it is still isn’t a substitute for real user traffic. You’re going to have to rely on hiring experienced Elixir developers (small talent pool), allow for long onboarding time (expensive), or provide extensive training (difficult). Personally for most cases, writing a sync test suite and just optimizing to keep it not to slow is probably more practical in the long term.
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