When comparing tagnames, it is possible that a tagname contains more
than one of the configured prerelease suffixes around the first
different character. After fixing a bug in the previous commit such a
tagname is sorted according to the contained suffix which comes first
in the configuration. This is, however, not quite the right thing to
do in the following corner cases:
1. $ git -c versionsort.suffix=-bar
-c versionsort.suffix=-foo-baz
-c versionsort.suffix=-foo-bar
tag -l --sort=version:refname 'v1*'
v1.0-foo-bar
v1.0-foo-baz
The suffix of the tagname 'v1.0-foo-bar' is clearly '-foo-bar',
so it should be listed last. However, as it also contains '-bar'
around the first different character, it is listed first instead,
because that '-bar' suffix comes first the configuration.
2. One of the configured suffixes starts with the other:
$ git -c versionsort.prereleasesuffix=-pre \
-c versionsort.prereleasesuffix=-prerelease \
tag -l --sort=version:refname 'v2*'
v2.0-prerelease1
v2.0-pre1
v2.0-pre2
Here the tagname 'v2.0-prerelease1' should be the last. When
comparing 'v2.0-pre1' and 'v2.0-prerelease1' the first different
characters are '1' and 'r', respectively. Since this first
different character must be part of the configured suffix, the
'-pre' suffix is not recognized in the first tagname. OTOH, the
'-prerelease' suffix is properly recognized in
'v2.0-prerelease1', thus it is listed first.
Improve version sort in these corner cases, and
- look for a configured prerelease suffix containing the first
different character or ending right before it, so the '-pre'
suffixes are recognized in case (2). This also means that
when comparing tagnames 'v2.0-pre1' and 'v2.0-pre2',
swap_prereleases() would find the '-pre' suffix in both, but then
it will return "undecided" and the caller will do the right thing
by sorting based in '1' and '2'.
- If the tagname contains more than one suffix, then give precedence
to the contained suffix that starts at the earliest offset in the
tagname to address (1).
- If there are more than one suffixes starting at that earliest
position, then give precedence to the longest of those suffixes,
thus ensuring that in (2) the tagname 'v2.0-prerelease1' won't be
sorted based on the '-pre' suffix.
Add tests for these corner cases and adjust the documentation
accordingly.
Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
51acfa9db5