run-tests: support per-line conditional output in tests Duplicating entire tests just because the output is different is both error prone and can make the tests harder to read. This harnesses the existing '(?)' infrastructure, both to improve readability, and because it seemed like the path of least resistance. The form is: $ test_cmd output (hghave-feature !) # required if hghave.has_feature(), else optional out2 (no-hghave-feature2 !) # req if not hghave.has_feature2(), else optional I originally extended the '(?)' syntax. For example, this: 2 r4/.hg/cache/checkisexec (execbit ?) pretty naturally reads as "checkisexec, if execbit". In some ways though, this inverts the meaning of '?'. For '(?)', the line is purely optional. In the example, it is mandatory iff execbit. Otherwise, it is carried forward as optional, to preserve the test output. I tried it the other way, (listing 'no-exec' in the example), but that is too confusing to read. Kostia suggested using '!', and that seems fine.