Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
not ok /fwupd/polkit-agent - ERROR:../src/fu-polkit-test.c:19:fu_polkit_agent_func: assertion failed (error == NULL): missing pkttyagent (FwupdError, 10)
It contains the error message which caused unit tests to fail.