[OE-core] shell script guidelines in oe-core? (was Re: [PATCH v4] create-pull-request: cleanup bashisms)

[Christopher Larson]

On Wed, Aug 12, 2015 at 11:27 PM, <Mikko.Rapeli at bmw.de> wrote:

> On Wed, Aug 12, 2015 at 10:51:26AM -0700, Christopher Larson wrote:
> > That reminds me, there's a shell portability issue / standards-complaince
> > issue that's not identified by shellcheck. Typically, to negate a
> bracket
> > expression in a regular expression, one uses ^, e.g. [^a-z] is everything
> > that isn't in the range a to z, but that's not the case in shell, e.g.
> at a
> > prompt or in a ${foo#<pattern>}:
> >
> >     "[...]a bracket expression as in XBD *RE Bracket Expression* , except
> > that the <exclamation-mark> character ( '!' ) shall replace the
> > <circumflex> character ( '^' ) in its role in a non-matching list in the
> > regular expression notation"
> >
> > So in shell, you'd want [!a-z] rather than [^a-z]. Nearly all shells
> handle
> > both, but the behavior of the latter is actually unspecified according to
> > the standard:
> >
> >     "A bracket expression starting with an unquoted <circumflex>
> character
> > produces unspecified results."
> >
> > I recently got bitten by this with one of my shell scripts on a system
> > running dash.
>
> Does checkbashisms warn about this?


Finally got around to checking, and yeah, checkbashisms does spot this one,
it's just shellcheck that doesn't (yet, opened a bug upstream).

-Chris


-- 
Christopher Larson
clarson at kergoth dot com
Founder - BitBake, OpenEmbedded, OpenZaurus
Maintainer - Tslib
Senior Software Engineer, Mentor Graphics
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.openembedded.org/pipermail/openembedded-core/attachments/20150814/08c58278/attachment-0002.html>