Right now ``./python -m test test_complex test_cmath`` only partially cover implementation of the complex object. Some code/branches are just inaccessible (e.g. L135-136 or ``mask <= 0`` on L166; line numbers are wrt to 54fbfa8d5e). There are only indirect tests for C-API functions (e.g. PyComplex_RealAsDouble, PyComplex_ImagAsDouble). <!-- gh-linked-prs --> ### Linked PRs * gh-109642 * gh-112452 * gh-112489 * gh-117449 <!-- /gh-linked-prs -->