Commit 6c86cabbe5 changed the command line interface to behave
a lot similar to that of github.com/coreos/toolbox, which makes things
easier for those switching over from it. Make it conditional so that
only those OS distributors who truly need it may enable it, and
restore the previous behaviour as the default.
The tests were updated to test the default behaviour that the vast
majority of users would be seeing. Ideally, the test suite would be run
twice with the migration path turned off and on. However, that would
require a more intrusive surgery of the test suite and likely make it
slower. It might not be worth the hassle because of the small number
of users who should be using the migration path.
Note that the copyright and license notices really must use C++-style
// line comments, because build constraints can only be preceded by
blank lines and other line comments. C-style /* */ block comments can't
precede the build constraints.
This reverts commit ca899c8a56 and parts
of commit 3aeb7cf288.
[1] go help buildconstraint
https://pkg.go.dev/cmd/go#hdr-Build_constraintshttps://github.com/containers/toolbox/pull/951
411147988b