"TestSocks 1" and IP addresses in requests using "safe" socks protocols result in misleading log messages
According to the man page, the TestSocks option causes Tor to "make a notice-level log entry for each connection to the Socks port indicating whether the request used a safe socks protocol or an unsafe one".
In case of "safe" socks protocols Tor however goes a bit further and always claims:
Your application (using socks(4a|5) to port 80) gave Tor a hostname, which means Tor will do the DNS resolve for you. This is good.
The message is printed even if the application actually gave Tor an IP address and not a hostname.
I think Tor should either verify that a hostname has been given, or the log message should be reworded to something like:
Your application (using socks(4a|5) to port 80) instructed Tor to take care of the DNS resolution itself if necessary. This is good.