The odd-range hack was introduced by 9afcfbca1710 for backward compatibility,
but it was too widely applied. I've checked cmdutil.revpair() at 1.6, and
found that ".:", ":0" and ":" are also handled as pairs. So let's enable the
hack only for "x:y", "x:", "y:" and ":".
test-revset.t is updated because "tip^::tip^ or tip^" shouldn't be taken as
an odd range. This patch adds "tip^:tip^" instead.
This patch is written for the default branch because parse() of the stable
branch lacks compatibility hack for "foo+bar" tag. If we want to mitigate the
issue in stable, we can add something like "and '::' in revs[0]".
Many tests didn't change back from subdirectories at the end of the tests ...
and they don't have to. The missing 'cd ..' could always be added when another
test case is added to the test file.
This change do that tests (99.5%) consistently end up in $TESTDIR where they
started, thus making it simpler to extend them or move them around.
