meson/docs/markdown/snippets/test_timeout.md

test() timeout and timeout_multiplier value <= 0

test(..., timeout: 0), or negative value, used to abort the test immediately but now instead allow infinite duration. Note that omitting the timeout keyword argument still defaults to 30s timeout.

Likewise, add_test_setup(..., timeout_multiplier: 0), or meson test --timeout-multiplier 0, or negative value, disable tests timeout.