Thank you very much. So do I still have to disclose that I lived there for half of the year?
Since you will be filing a CA part year resident tax return, only report your income from the date you moved to California on the CA state tax return.
I didn't work at all when I came back to CA for the year. My only employment for 2019 was in TN from January-July. Do I still have to file for CA?
No, you do not have to file a CA return if you did not have any kind of income while you were a CA part year resident.