Re: [PATCH] t/perf: correctly align non-ASCII descriptions in output

[Jeff King <peff@peff.net>]

On Fri, Apr 21, 2017 at 11:28:42PM +0200, Ævar Arnfjörð Bjarmason wrote:

> > I thought there was some "use" flag we could set to just make all of our
> > handles utf8. But all I could come up with was stuff like PERLIO and
> > "perl -C". Using binmode isn't too bad, though (I think you could
> > just do it as part of the open, too, but I'm not sure if antique
> > versions of perl support that).
> 
> [Debugging perl encoding issues is one of the many perks of my dayjob]
> 
> Using binmode like this is about as straightforward as you can get,
> the former occurrence could be equivalently replaced by:
> 
>     utf8::decode(my $line = <$fh>);
> 
> But better just to mark the handle as utf8. There's a fancier way to
> do it as part of the three-arg-open syntax, but I couldn't remember
> whether all the perl versions we support have it.

Yeah, I agree marking the handle is better. binmode is pretty
straightforward, but we'd have to remember to manually set it if we add
any other handles. That's probably not a big deal in this particular
script, though, which is pretty short.

> About the "use" flag, you're probably thinking of the confusingly
> named "use utf8", but that's to set your source code to utf8, not your
> handles, e.g.:
> 
> $ perl -CA -MDevel::Peek -wE 'use utf8; my $日本語 = shift; Dump $日本語' æ
> SV = PV(0x12cc090) at 0x12cded8
>   REFCNT = 1
>   FLAGS = (PADMY,POK,pPOK,UTF8)
>   PV = 0x12de460 "\303\246"\0 [UTF8 "\x{e6}"]
>   CUR = 2
>   LEN = 16
> 
> As you can see people got a bit overexcited about Unicode in the 90s.

Yeah, I know "use utf8" doesn't work for that, but I was thinking there
was some other trick. Digging...ah, here it is:

  use open ':encoding(utf8)'

No clue how portable that is. For such a small script it may be better
to just stick with vanilla binmode().

-Peff