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title: "Testing async code and mocks · vuejs.school"
description: "Run a composable inside withSetup(), replace the network with vi.mock() or MSW, wait with flushPromises(), and move time on with fake timers."
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> Index of every page on this site: [llms.txt](https://vuejs.school/llms.txt)

# **Testing async code and mocks**

Run a composable inside withSetup(), replace the network with vi.mock() or MSW, wait with flushPromises(), and move time on with fake timers.

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