Re: TestLib::command_fails_like enhancement

On 11/11/19 4:28 PM, Mark Dilger wrote:
>
>
>>>>>
>>>>
>>>> On further consideration, I'm wondering why we don't just
>>>> unconditionally use a closed input pty for all these functions (except
>>>> run_log). None of them use any input, and making the client worry
>>>> about
>>>> whether or not to close it seems something of an abstraction break.
>>>> There would be no API change at all involved in this case, just a
>>>> bit of
>>>> extra cleanliness. Would need testing on Windows, I'll go and do that
>>>> now.
>>>>
>>>>
>>>> Thoughts?
>>>
>>> That sounds a lot better than your previous patch.
>>>
>>> PostgresNode.pm and TestLib.pm both invoke IPC::Run::run.  If you
>>> change all the invocations in TestLib to close input pty, should you
>>> do the same for PostgresNode?  I don't have a strong argument for
>>> doing so, but it seems cleaner to have both libraries invoking
>>> commands under identical conditions, such that if commands were
>>> borrowed from one library and called from the other they would behave
>>> the same.
>>>
>>> PostgresNode already uses TestLib, so perhaps setting up the
>>> environment can be abstracted into something, perhaps TestLib::run,
>>> and then used everywhere that IPC::Run::run currently is used.
>>
>>
>>
>> I don't think we need to do that. In the case of the PostgresNode.pm
>> uses we know what the executable is, unlike the the TestLib.pm cases.
>> They are our own executables and we don't expect them to be doing
>> anything funky with /dev/tty.
>
> Ok.  I think your proposal sounds fine.

Here's a patch for that. The pty stuff crashes and burns on my Windows
test box, so there I just set stdin to an empty string via the usual
pipe mechanism.

cheers

andrew

--
Andrew Dunstan https://www.2ndQuadrant.com
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