Re: [RESEND PATCH v2 0/5] t: replace incorrect test_must_fail usage (part 6)

Denton Liu [off-list ref] writes:

The overall scope of these patches is to replace inappropriate uses of
test_must_fail. IOW, we should only allow test_must_fail to run on `git`
and `test-tool`. Ultimately, we will conclude by making test_must_fail
error out on non-git commands. An advance view of the final series can
be found here[1].

This is the sixth and final(!) part. It cleans up instances of
`test_must_fail` that were introduced since the effort began. In
addition, it finally flips the switch and makes test_must_fail only
allow a whitelist of commands.

This series is based on the merge of 'master' and
'dl/test-must-fail-fixes-5'. In addition, this series was tested by
merging with 'seen~1' (to ignore the reftable failures) to ensure no
in-flight topics will require more changes.

The first part can be found here[2]. The second part can be found
here[3]. The third part can be found here[4]. The fourth part can be
found here[5]. The fifth part can be found here[6].

Changes since v1:

* Add a code comment to force_color()

* Do not allow nested env's in test_must_fail_acceptable()

* Clean up the env-processing case code

* Give an example on how to use `!`.

Thanks for a resend.  Now part #5 is in 'master', I can queue these
directly on top.