:set -fobject-code
-- ^ Without this no recompilation happens at all in ghci, but that's a bug for
-- another ticket.

:l plugin-recomp-test.hs

-- switching to an impure plugin triggers recomp.
:! echo ==ImpurePlugin.0 >&2
:set -fclear-plugins -fplugin ImpurePlugin
:l plugin-recomp-test.hs

-- ..forever, this also triggers recomp.
:! echo ==ImpurePlugin.1 >&2
:l plugin-recomp-test.hs

-- switching from impure to pure plugin triggers recomp.
:! echo ==PurePlugin.0 >&2
:set -fclear-plugins -fplugin PurePlugin
:l plugin-recomp-test.hs

-- switching to a fingerprint plugin triggers recomp.
:! echo ==FingerprintPlugin.0 >&2
:set -fclear-plugins -fplugin FingerprintPlugin
:l plugin-recomp-test.hs

-- same fingerprint plugin doesn't trigger recomp.
:! echo ==FingerprintPlugin.1 >&2
:l plugin-recomp-test.hs

-- switching from fingerprint to pure plugin triggers recomp.
:! echo ==PurePlugin.1 >&2
:set -fclear-plugins -fplugin PurePlugin
:l plugin-recomp-test.hs