How should you manage event-loop and fixture scope in pytest-asyncio?

Aligns pytest-asyncio discovery, loop lifetime, and async fixture ownership without custom loop competition.

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Pytest-asyncio runs async tests in managed event loops, with function scope giving the strongest isolation by default. Async fixtures also have a loop scope, and a long-lived fixture cannot safely depend on a loop that disappears sooner. I keep neighboring tests on a consistent loop scope and widen it only when an expensive async resource requires that lifetime. I let the plugin own loop creation instead of installing a competing custom loop fixture.

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Aligns pytest-asyncio discovery, loop lifetime, and async fixture ownership without custom loop competition.

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Aligns pytest-asyncio discovery, loop lifetime, and async fixture ownership without custom loop competition.
Pytest-asyncio runs async tests in managed event loops, with function scope giving the strongest isolation by default. Async fixtures also have a loop scope, and a long-lived fixture cannot safely depend on a loop that disappears sooner. I keep neighboring tests on a consistent loop scope and widen it only when an expensive async resource requires that lifetime. I let the plugin own loop creation instead of installing a competing custom loop fixture.
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Strict mode handles only explicitly marked asyncio tests and properly decorated async fixtures, which is useful when several async libraries or plugins coexist. Auto mode claims async tests and fixtures more broadly. Whichever mode I choose, I configure it once and make fixture loop scope explicit where lifetime matters. Errors such as scope mismatch or event loop closed usually mean resource lifetime and loop lifetime no longer agree.

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Overriding the event loop fixture without need
Mixing loop scopes arbitrarily in one module
Widening scope to hide event-loop-closed failures

How should you manage event-loop and fixture scope in pytest-asyncio?

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