[tap-l] stream concatenation question

[Ovid]

----- Original Message ----
> From: EBo <ebo at users.sourceforge.net>


> The verbose output of Test-Harness's prove utility  essentially
> concatenates the results of various producers, but this  concatenated output
> cannot then be re-parsed by a consumer.  This may  run counter to the draft
> standards directive "For maximum compatibility, it  may be produced by any
> TAP producer, and must then be consumable by any TAP  consumer."


Strictly speaking, prove is not a TAP producer. It merely runs the tests. It's 
Test::Harness (via TAP::Harness) which consumes the TAP which in turn is 
produced by the tests (and this is *usually* Perl's Test::Builder, but not 
always).  prove's output should not be considered TAP.

Now that I've TAP-danced around your question: this is legacy.  After I 
implemented subtests, I considered adding an extra switch to prove (to be passed 
to the harness, perhaps) to allow the output to be rendered as subtests, 
effectively allows concatenated streams and having the output be valid TAP. 
 There was never a pressing need for it, so I didn't bother.

> Is there already a method for dealing with concatenated  streams?  
> 
> If there is not, looking at the draft standards grammar,  a potential
> solution is to add an optional Test-Name to the TAP's Header EBNF  grammar:
> 
>   Header      = [Comments] [Version]  [Comments] [Test-Name]
>   Test-Name   = "NAME" SP Name-String [SP  Description]
>   Name-String = 1*(%x21-22 %x24-FF)  ; printable UTF8  without SPACE or "#"
> 
> Perl's Test-Harness already adds the test name to  the verbose output, but
> it does so in a way that is not guaranteed to be  reparsable.  Adding this
> name tag allows for unambiguous regrouping of  the output.


You know, I think this would solve some other issues I've had with trying to 
store TAP history.

Cheers,
Ovid

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