Re: Using LibPq in TAP tests via FFI

On 2024-Jun-17, Andrew Dunstan wrote:

> On 2024-06-17 Mo 5:07 AM, Alvaro Herrera wrote:

> > You made this function join the tuples from multiple queries together,
> > but the output format doesn't show anything for queries that return
> > empty. I think this strategy doesn't cater for the case of comparing
> > results from multiple queries very well, because it might lead to sets
> > of queries that return empty result for different queries reported as
> > identical when they aren't. Maybe add a separator line between the
> > results from each query, when there's more than one? (Perhaps just
> > "join('--\n', @results)" in that last line does the trick?)
>
> psql doesn't do that, and this is designed to mimic psql's behaviour. We
> could change that of course. I suspect none of the uses expect empty
> resultsets, so it's probably somewhat moot.

True -- I guess my comment should really be directed to the original
coding of the test in test_index_replay. I think adding the separator
line makes it more trustworthy.

Probably you're right that the current code of in-core tests don't care
about this, but if we export this technique to the world, I'm sure
somebody somewhere is going to care.

--
Álvaro Herrera 48°01'N 7°57'E — https://www.EnterpriseDB.com/
"The Gord often wonders why people threaten never to come back after they've
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