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-libs/atf-0.23::gentoo  619 KiB
[ebuild  N     ] dev-lua/lutok-0.6::gentoo  USE="-test" LUA_SINGLE_TARGET="lua5-4 -lua5-3" 47 KiB
[ebuild  N     ] dev-util/kyua-0.13-r3::gentoo  USE="-test" 649 KiB

Total: 3 packages (3 new), Size of downloads: 1313 KiB