This fixes --version integration test on CentOS, as noticed by
https://github.com/projectatomic/skopeo/pull/91 . The underlying cause
is:
- Makefile builds with -ldflags "-X var=value", while go 1.4.2 only
supports "-X var value". This causes CentOS builds to be built
without the specific commit information
- The --version integration test assumes that commit information will
always follow the version number.
Changing either one of these would fix the build, changing the
integration test has the advantage that we don't have to use the
obsolete -X syntax and suffer warnings on newer Go versions.
- consumeAndLogOutputs
- assertSkopeoSucceeds
- assertSkopeoFails
- runCommandWithInput
All of these allow running commands as one-liners with no call-site
error handling, making tests much more readable.
Also modifies TestNoNeedAuthToPrivateRegistryV2ImageNotFound to use
check.Matches instead of manual strings.Contains conditions, which is
shorter and more consistent with the assertSkopeo... calls.
