Re: treat .xpi as archive file

[Dave Love]

Jason Rumney <address@hidden> writes:

> Richard Stallman <address@hidden> writes:
>
>>     Yes, in principle (like compressed files), but please don't mess with
>>     that now.
>>
>> I tend to agree it is better to recognize these by filenames.  That is
>> because there is a very strong convention to use those filenames for
>> these files.  People won't, and shouldn't, expect Emacs to treat
>> something as a ZIP file if it doesn't have the right file name.

I don't think zip files are much of a special case.  I _am_ asking for
.xpi files to be treated as zip files, similarly to .jar; that's what
archive-mode does.

> I disagree. While we might not want to mess with this before release,
> the file extensions used for zip files are multiplying, and I don't
> think we should expect users to know that a file with the extension
> .xpi, .jar, .ear, .war or whatever else comes in future (are Open
> Office files also zip files?) is actually a zip file so they can set
> Emacs up to recognize it correctly. I don't think we can guess all the
> extensions that developers will use for zip archives with specific
> meaning to their program.

I think you'll find problems in various places doing this, e.g. with
MIME handling, though probably because the relevant code doesn't DTRT.
It may or may not be the right thing to do, but you definitely don't
want to mess with it now.  It would probably make sense to rationalize
such things with MIME types, i.e. you can assume a MIME type from the
file extension like with mime.types, or the contents like with `file'.