These are the packages that would be merged, in order:

Calculating dependencies ... done!
Dependency resolution took 1.01 s (backtrack: 0/20).

[ebuild  N     ] dev-perl/HTML-Form-6.130.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 46 KiB
[ebuild  N     ] dev-perl/HTML-Tree-5.70.0-r1::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 147 KiB
[ebuild  N     ] dev-perl/WWW-Mechanize-2.190.0::gentoo  USE="-test" PERL_FEATURES="ithreads (-debug) -quadmath" 193 KiB

Total: 3 packages (3 new), Size of downloads: 386 KiB