Comment # 1 on bug 934328 from Michael Schr�der

ruby-common-2.1 needs either ruby2.1-rubygem-gem2rpm or
ruby2.2-rubygem-gem2rpm. The solver decides to install ruby2.1-rubygem-gem2rpm.
Later, ruby-2.2 is also needed. But not ruby2.2-rubygem-gem2rpm, which would
trigger libsolv's autominimization.