This module is a subclass of LWP::UserAgent which overrides a few key
low-level methods that are concerned with actually sending your request over
the network, allowing an interception of that request and simulating a
particular response. This greatly facilitates testing of client networking
code where the server follows a known protocol.

The synopsis describes a classic case where you want to test how your
application reacts to various responses from the server. This module will let
you send back various responses depending on the request, without having to
set up a real server to test against. This can be invaluable when you need to
test edge cases or error conditions that do not normally arise from the
server.

There are a lot of different ways you can set up the response mappings, and
hook into this module; see the documentation for the individual interface
methods.