1 Checks incomplete datetime formats are rejected.
3 On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
7 PASS getUserAgentShadowTextContent(input) is "Week09 1999"
8 Invalid format, fallback to yyyy-'W'ww
9 PASS getUserAgentShadowTextContent(input) is "1999-W09"
10 PASS getUserAgentShadowTextContent(input) is "1999-W09"
11 PASS successfullyParsed is true