[PATCH] patch: decode e-mail headers

[Martin Geisler]

funman at videolan.org writes:

> # HG changeset patch
> # User Rafaël Carré <funman at videolan.org>
> # Date 1382444275 -7200
> #      Tue Oct 22 14:17:55 2013 +0200
> # Branch stable
> # Node ID e8c0f97e42ca9e09b4000245bd713f03e5d72038
> # Parent  2c886dedd9021598b6290d95ea0f068731ea4e2b
> patch: decode e-mail headers
>
>     Change commits from:
> user:        =?UTF-8?q?Rafa=C3=ABl=20Carr=C3=A9?= <funman at videolan.org>
>     to:
> user:        Rafaël Carré <funman at videolan.org>
>
> diff -r 2c886dedd902 -r e8c0f97e42ca mercurial/patch.py
> --- a/mercurial/patch.py	Mon Oct 21 10:50:58 2013 -0700
> +++ b/mercurial/patch.py	Tue Oct 22 14:17:55 2013 +0200
> @@ -12,6 +12,7 @@
>  # load. This was not a problem on Python 2.7.
>  import email.Generator
>  import email.Parser
> +from email.header import decode_header

We normally only import modules and reference functions with

  module.function

This is because we have a demand-import system in place that can delay
loading the module until it is really needed. This makes Mercurial start
faster.

>  from i18n import _
>  from node import hex, short
> @@ -162,6 +163,25 @@
>      Any item in the returned tuple can be None. If filename is None,
>      fileobj did not contain a patch. Caller must unlink filename when done.'''
>  
> +    def header_decode(h):
> +        '''Decode ?=UTF-8? from e-mail headers.'''
> +        if h is None:
> +            return None
> +        res = ''
> +        pairs = decode_header(h)

You define a header_decode function and there is apparently already a
decode_header function in scope -- that looks confusing to me :-)

The names are so similar that I wouldn't know what the difference is
between the two functions. Maybe you can come up with a better name for
the new function.

> +        if pairs is None:
> +            return None
> +        n = len(pairs)
> +        pair = 0
> +        for p in pairs:
> +            pair += 1
> +            if p[1] == 'utf-8' or p[1] is None:

Does this mean that you only handle UTF-8 encoded headers? What about
ISO-8859-* encoded headers?

-- 
Martin Geisler