Re: [gentoo-portage-dev] [PATCH] Make use of optparse to fix argument parsing for Python 2.6 in bin/chpathtool.py.

[Sebastian Luther]

Am 29.12.2013 03:21, schrieb Tom Wijsman:
> ---
>  bin/chpathtool.py | 45 ++++++++++++++++++++++++++++++++++++---------
>  1 file changed, 36 insertions(+), 9 deletions(-)
>
> diff --git a/bin/chpathtool.py b/bin/chpathtool.py
> index aa3b7d4..0cb5d64 100755
> --- a/bin/chpathtool.py
> +++ b/bin/chpathtool.py
> @@ -13,6 +13,12 @@ import sys
>
>  from portage.util._argparse import ArgumentParser
>
> +# Argument parsing compatibility for Python 2.6 using optparse.
> +if sys.hexversion < 0x2070000:
> +	from optparse import OptionParser
> +
> +from optparse import OptionError
> +
>  CONTENT_ENCODING = 'utf_8'
>  FS_ENCODING = 'utf_8'
>
> @@ -147,15 +153,36 @@ def chpath_inplace_symlink(filename, st, old, new):
>  def main(argv):
>
>  	parser = ArgumentParser(description=__doc__)
> -	parser.add_argument('location', default=None,
> -		help='root directory (e.g. $D)')
> -	parser.add_argument('old', default=None,
> -		help='original build prefix (e.g. /)')
> -	parser.add_argument('new', default=None,
> -		help='new install prefix (e.g. $EPREFIX)')
> -	opts = parser.parse_args(argv)
> -
> -	location, old, new = opts.location, opts.old, opts.new
> +	try:
> +		parser.add_argument('location', default=None,
> +			help='root directory (e.g. $D)')
> +		parser.add_argument('old', default=None,
> +			help='original build prefix (e.g. /)')
> +		parser.add_argument('new', default=None,
> +			help='new install prefix (e.g. $EPREFIX)')
> +		opts = parser.parse_args(argv)
> +
> +		location, old, new = opts.location, opts.old, opts.new
> +	except OptionError:
> +		# Argument parsing compatibility for Python 2.6 using optparse.
> +		if sys.hexversion < 0x2070000:
> +			parser = OptionParser(description=__doc__,
> +				usage="usage: %prog [-h] location old new\n\n" + \
> +				"  location: root directory (e.g. $D)\n" + \
> +				"  old:      original build prefix (e.g. /)\n" + \
> +				"  new:      new install prefix (e.g. $EPREFIX)")
> +
> +			(opts, args) = parser.parse_args()
> +
> +			if len(args) != 3:
> +				parser.print_usage()
> +				print("%s: error: expected 3 arguments, got %i"
> +					% (__file__, len(args)))
> +				return
> +
> +			location, old, new = args[0:3]
> +		else:
> +			raise
>
>  	is_text_file = IsTextFile()
>
>

Patch looks good.

While I do not really like the approach, I didn't see a better way.
Tweaking portage.util._argparse.ArgumentParser would just mean to
reinvent argparse.

Sebastian