[libvirt] [PATCH 2/2] Added syntax-check rule for return with parentheses

[Osier Yang]

On 03/22/2012 07:33 PM, Martin Kletzander wrote:
> After cleanup introduced with previous commit, there is a need for
> syntax-check rule taking care of return(). Regexp used in 'prohibit'
> parameter is taken from the cleanup commit and modified so it fits
> 'grep -E' format. Semicolon at the end is needed, otherwise the regexp
> could match return with cast.
>
> No exception is needed thanks to files excused by default. The
> exception is not even needed for python files because 1) when
> returning a tuple, you can still omit parentheses around (unless there
> is only one value inside, but that's very unusual case),  2) return in
> python doesn't need semicolon at the end of statement when there is no
> statement following (and statement following 'return' doesn't make
> sense).

This forces the Python coding style actually, prohibiting one
writes Python codes like:

def test():
     return (1);

def test1():
     return (1,2,3);

regardless of whether coding like this is good or bad, usual or
unsual, they are legal in Python, and we don't say they are not
allowed in HACKING or somewhere else.

Not sure if we should allow this, even we will allow that, we
need to document it somewhere, or more clear and specific for .py
files in halt message.

> ---
>   cfg.mk |    6 ++++++
>   1 files changed, 6 insertions(+), 0 deletions(-)
>
> diff --git a/cfg.mk b/cfg.mk
> index 24e6a69..59b07ef 100644
> --- a/cfg.mk
> +++ b/cfg.mk
> @@ -469,6 +469,12 @@ sc_prohibit_xmlURI:
>   	halt='use virURI(Parse|Format), not xml(ParseURI|SaveUri)'	\
>   	  $(_sc_search_regexp)
>
> +# we don't want old old-style return with parentheses around argument
> +sc_prohibit_return_as_function:
> +	@prohibit='\<return *\(([^()]*(\([^()]*\)[^()]*)*)\) *;'    \
> +	halt='avoid extra () with return statements'                \
> +	  $(_sc_search_regexp)
> +
>   # ATTRIBUTE_UNUSED should only be applied in implementations, not
>   # header declarations
>   sc_avoid_attribute_unused_in_header: