Re: [PATCH] kunit: tool: print clearer error message when there's no TAP output

[Daniel Latypov]

On Tue, Mar 29, 2022 at 10:17 PM David Gow <davidgow@xxxxxxxxxx> wrote:
>
> On Wed, Mar 30, 2022 at 5:43 AM Daniel Latypov <dlatypov@xxxxxxxxxx> wrote:
> >
> > Before:
> > $ ./tools/testing/kunit/kunit.py parse /dev/null
> > ...
> > [ERROR] Test : invalid KTAP input!
> >
> > After:
> > $ ./tools/testing/kunit/kunit.py parse /dev/null
> > ...
> > [ERROR] Test <missing>: could not find any KTAP output!
> >
> > This error message gets printed out when extract_tap_output() yielded no
> > lines. So while it could be because of malformed KTAP output from KUnit,
> > it could also be due to to not having any KTAP output at all.
> >
> > Try and make the error message here more clear.
> >
> > Signed-off-by: Daniel Latypov <dlatypov@xxxxxxxxxx>
> > ---
>
> At first I thought that this was "working as intended", but I agree
> that it's a bit confusing, so changing it is for the best.
> (And there's no sense getting too bogged down in the philosophical
> difference between "invalid TAP" and "not valid TAP" :-))

extract_tap_output() returning something means it just saw a TAP header.
So this error realistically only happens when there's no TAP at all :P

My allusion to malformed KTAP is in the sense that
 KTA<random stuff>P ver<more stuff>sion 1
is malformed.

We could potentially be more completely precise w/ our error message
and say "no K?TAP header found", but I initially thought this might be
a bit more user-friendly.