test utils broken due to observer map

Describe the bug

There’s a cache of observers here: https://github.com/thebuilder/react-intersection-observer/blob/ef0bb84363601992d55a48e26ee19faeb3dd0303/src/observe.ts#L3

This prevents new IntersectionObservers from being created.

test-utils maintains a map of IntersectionObserver to observed Item: https://github.com/thebuilder/react-intersection-observer/blob/d3608a6b6ed21d6e39daaf65005d99514702ec3f/src/test-utils.ts#L50

Entries are inserted when new IntersectionObservers are constructed. This map is used to iterate over all observers when using the mock functions. However, the map is cleared after every test. Due to the observer cache mentioned above, subsequent tests will reuse an observer which is no longer in the test-utils observer map. This breaks all the mock functions if the same useInView is tested in multiple it blocks.

To Reproduce Try and recreate the issue in a Codesandbox:

Hopefully the description above is clear enough.

Expected behavior Mock functions should work across multiple tests

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Desktop (please complete the following information):

• OS: [e.g. iOS]
• Browser [e.g. chrome, safari]
• Version [e.g. 22]

Smartphone (please complete the following information):

• Device: [e.g. iPhone6]
• OS: [e.g. iOS8.1]
• Browser [e.g. stock browser, safari]
• Version [e.g. 22]

Additional context Add any other context about the problem here.

[thebuilder]

Good catch. Should be simple enough to fix - The afterEach needs to call unobserve on each observer before clearing it.

[thebuilder]

@yepitschunked I’ve reverted the change in #523 - test-utils was never suppose to import any of the files, but because it’s compiled with TypeScript it has no knowledge of the bundles.

I’ll need to figure out a better way if this is an actual issue. Can you write out the basic steps you take to cause the issue, so I can replicate it in a test - I haven’t actually been able to do it myself.

Reading your description again, I think the issue might be elsewhere - Are the components unmounted after each it? https://testing-library.com/docs/react-testing-library/api/#cleanup