Re: [PATCH 1/3] python extended prompt: Use os.getcwd() instead of os.getcwdu()

[Joel Brobecker <brobecker@adacore.com>]

> It seems like using os.getcwdu() here is wrong both for Python 2 and Python 3.
> 
> For Python 2, this returns a 'unicode' object, which tries to get concatenated
> to a 'str' object in substitute_prompt. The implicit conversion works when the
> unicode string contains no accent. When it does contain an accent though,
> displaying the prompt results in the following error:
> 
> (gdb) set extended-prompt \w
> ...
>   File "/home/simark/build/binutils-gdb-python2/gdb/data-directory/python/gdb/prompt.py", line 138, in substitute_prompt
>     result += str(cmd(arg))
> UnicodeEncodeError: 'ascii' codec can't encode character u'\xe9' in position 49: ordinal not in range(128)
> 
> When using os.getcwd() instead, it works correctly. I suppose that Python does
> the necessary decoding internally.
> 
> For Python 3, this method simply does not exist. It works fine with os.getcwd().
> 
> gdb/ChangeLog:
> 
> 	* python/lib/gdb/prompt.py (_prompt_pwd): Use os.getcwd() instead of
> 	os.getcwdu().

I'd like to have other people's opinion on this, as I am not sure.

I _think_ that the patch is not making things worse for us,
while making things a little better in situations as the above.
So, based on that, I'd be inclined to apply it.

However, I think the long term fix would be, I believe, to switch
the entire thing to unicode. With Python3, it's automatic, but
with Python2, we might have to add 'u'-s on every piece of string
in the module, and also add some conversions here and there.
That's why I am thinking that the long term fix should be a blocker
for this patch.

Thoughts?

> ---
>  gdb/python/lib/gdb/prompt.py | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/gdb/python/lib/gdb/prompt.py b/gdb/python/lib/gdb/prompt.py
> index d99f2ea..04adbfb 100644
> --- a/gdb/python/lib/gdb/prompt.py
> +++ b/gdb/python/lib/gdb/prompt.py
> @@ -21,7 +21,7 @@ import os
>  
>  def _prompt_pwd(ignore):
>      "The current working directory."
> -    return os.getcwdu()
> +    return os.getcwd()
>  
>  def _prompt_object_attr(func, what, attr, nattr):
>      """Internal worker for fetching GDB attributes."""
> -- 
> 2.1.3

-- 
Joel