skeema / skeema / 21974291124

92%

push

github

flavor: further improvements for future-proofing MySQL 10+

This commit expands on the previous one to provide further disambiguation
between MariaDB 10+ and any upcoming MySQL 10+ version series, for situations
where OS packages override @@global.version_comment in their server builds.

When introspecting server global variables, we now append version-gated
comments to the @@global.version_comment string in a way which should
accurately distinguish between MariaDB 10+ vs MySQL 10+ in all cases. This
takes advantage of the fact that MariaDB has its own /*M! ... */ comment
syntax which MySQL ignores, and meanwhile MariaDB ignores standard MySQL
/*!50701 ... */ comments as long as the gated version is between 5.7 and 9.9.

This new logic inherently doesn't append anything for MySQL 5.6 or lower,
but we already handle that case by assuming MySQL if the major version is 5
and the vendor cannot be detected.

The only downside to this approach is that it may misdetect "NewSQL" databases
that pretend to be MySQL, if they support /*!50701 ... */ comments. Skeema
does not support such systems, so "unknown flavor" would be preferable in
these cases, but it isn't essential.

14 of 14 new or added lines in 2 files covered. (100.0%)

10840 of 11721 relevant lines covered (92.48%)

1.11 hits per line