X_TEST_POLICY_EXPECTED
Means
a matcher expected a policy and got something else
Typical cause
toDenyPolicy answered pass:false for a receiver that is not a policy, so .not.toDenyPolicy PASSED on undefined or a typo. The receiver is checked synchronously and refused with this code, under .not too
Fix
expect(post.policy).toDenyPolicy(ctx) — pass the policy object (@ultimat3/policy's, with run() or evaluate()), never the action or its result