Re: Regression test coverage of GiST index build is awful

On Wed, Apr 24, 2019 at 9:31 PM Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> This tells a pretty scary story:
>
> https://coverage.postgresql.org/src/backend/access/gist/index.html
>
> In particular, gistbuildbuffers.c is not entered *at all*, and
> gistbuild.c is only 21% covered.
>
> I noticed this after adding an assertion that I expected
> gistInitBuildBuffers to fail on, and nonetheless getting
> through check-world just fine.
>
> Why is this so bad? It's not like the gist regression test isn't
> ridiculously expensive already; I'd have expected it to provide
> darn near 100% coverage for what it's costing in runtime.

I don't think there is any idea behind this. Seems to be just oversight.

Do you like me to write a patch improving coverage here?

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company