[Mesa-dev] [PATCH 02/27] glapi: gl_table.py: replace getopt with argparse.

[Jose Fonseca]

On 21/05/15 02:02, Dylan Baker wrote:
> From: Dylan Baker <dylanx.c.baker at intel.com>
>
> This results in slightly less code, but code that is much more readable.
> It has the advantage of putting everything together in one place, all of
> the code is self documenting, help messages are auto-generated, choices
> are automatically enforced, and the syntax is much less C like, taking
> advantage of python features and idioms.
>
> Signed-off-by: Dylan Baker <dylanx.c.baker at intel.com>
> ---
>   src/mapi/glapi/gen/gl_table.py | 70 ++++++++++++++++++++----------------------
>   1 file changed, 33 insertions(+), 37 deletions(-)
>
> diff --git a/src/mapi/glapi/gen/gl_table.py b/src/mapi/glapi/gen/gl_table.py
> index 3245625..30903fd 100644
> --- a/src/mapi/glapi/gen/gl_table.py
> +++ b/src/mapi/glapi/gen/gl_table.py
> @@ -26,8 +26,7 @@
>   # Authors:
>   #    Ian Romanick <idr at us.ibm.com>
>
> -import sys
> -import getopt
> +import argparse
>
>   import gl_XML
>   import license
> @@ -203,45 +202,42 @@ class PrintRemapTable(gl_XML.gl_print_base):
>           return
>
>
> -def show_usage():
> -    print "Usage: %s [-f input_file_name] [-m mode] [-c ver]" % sys.argv[0]
> -    print "    -m mode   Mode can be 'table' or 'remap_table'."
> -    print "    -c ver    Version can be 'es1' or 'es2'."
> -    sys.exit(1)
> +def _parser():
> +    """Parse arguments and return a namespace."""
> +    parser = argparse.ArgumentParser()
> +    parser.add_argument('-f', '--filename',
> +                        type=gl_XML.parse_GL_API,
> +                        default='gl_API.xml',


This patch is causing problems on one of my Windows build machines.

It looks like argparse will call gl_XML.parse_GL_API() with the default 
'gl_API.xml' value, _even_ when one specifies -f argument in the command 
line.

I think the problem might be with particular version of argparse 
implementations, not the Windows OS.  This was with Python 2.7.3 BTW.


I could upgrade python, but using argparse' type arguments like this 
seems a bad idea regardless.  Not only argparse implementation can't be 
trusted, but also gl_XML.parse_GL_API takes multiple arguments, so it's 
not a straightforward constructor.

For example, src/mapi/glapi/gen/gl_procs.py has this

     api_type = lambda x: gl_XML.parse_GL_API(x, glX_XML.glx_item_factory())

     parser = argparse.ArgumentParser()
     parser.add_argument('-f', '--filename',
                         type=api_type,
     [...]

Which looks quite hard to read IMO over simply doing

     api =  gl_XML.parse_GL_API(args.file_name, glX_XML.glx_item_factory()


I'm going to undo these hunks, and I'm going to take the liberty of 
pushing this as I got no good build over the extended weekend, so we've 
been totally blind to regressions on this platform over this period.

Jose