portage-ng / portage / app-arch / tar / 1.35-r1
pmerge --pretend --verbose
[ebuild     U  ] app-arch/tar-1.35-r1::gentoo [1.35::gentoo] USE="acl nls xattr -minimal (-selinux) -test% -verify-sig" 2.2 MiB

Total: 1 package (1 upgrade), Size of downloads: 2.2 MiB


 * Running sanity checks...
>>> app-arch/tar-1.35-r1: failed pkg_pretend
 /Volumes/Disk 1/gentoo-prefix/usr/lib/pkgcore/lib/pkgcore/ebd/.generated/libs/8/pkg_pretend: line 144: [[: invalid regular expression `': empty (sub)expression
  * ERROR: app-arch/tar-1.35-r1:: failed (pretend phase):
  *   USE flag 'test' not in IUSE for app-arch/tar-1.35-r1
  * 
  * Call stack:
  *    isolated-functions.bash, line  333:  called pkg_pretend
  *                ebuild.bash, line 1128:  called check_space
  *                ebuild.bash, line  953:  called use 'test'
  *                pkg_pretend, line  145:  called die
  * 
  * Working directory: '/var/tmp/portage'

!!! Sanity checks failed, exiting...

Wall time
0.705 s vs. 0.006 s for portage-ng