bug#11839: teach some url code about .xz files

bug#11839: teach some url code about .xz files

[Liam Stitt]

Hi.  The code in lisp/url knows about .gz and .bz2 files, but not about the
more recent .xz variety.  These two trivial patches correct this:

*** url-file.el~	2012-01-16 02:12:46.000000000 -0700
--- url-file.el	2012-07-01 20:26:10.000000000 -0600
*************** can do automatic decompression for them,
*** 41,47 ****
  'foo.gz' exists, even though the FTP server would happily serve it up
  to them."
    (let ((scratch nil)
! 	(compressed-extensions '("" ".gz" ".z" ".Z" ".bz2"))
  	(found nil))
      (while (and compressed-extensions (not found))
        (if (file-exists-p (setq scratch (concat fname (pop compressed-extensions))))
--- 41,47 ----
  'foo.gz' exists, even though the FTP server would happily serve it up
  to them."
    (let ((scratch nil)
! 	(compressed-extensions '("" ".gz" ".z" ".Z" ".bz2" ".xz"))
  	(found nil))
      (while (and compressed-extensions (not found))
        (if (file-exists-p (setq scratch (concat fname (pop compressed-extensions))))
*************** to them."
*** 178,183 ****
--- 178,184 ----
  			     (\.uue "x-uuencoded")
  			     (\.hqx "x-hqx")
  			     (\.bz2 "x-bzip2")
+ 			     (\.xz "x-xz")
  			     (otherwise nil)))
  
      (if (file-directory-p filename)

*** url-vars.el~	2012-07-01 19:48:37.000000000 -0600
--- url-vars.el	2012-07-01 20:25:46.000000000 -0600
*************** variable."
*** 152,158 ****
  				    (".uue" . "x-uuencoded")
  				    (".hqx" . "x-hqx")
  				    (".Z"  . "x-compress")
! 				    (".bz2"  . "x-bzip2"))
    "An alist of file extensions and appropriate content-transfer-encodings."
    :type '(repeat (cons :format "%v"
  		       (string :tag "Extension")
--- 152,159 ----
  				    (".uue" . "x-uuencoded")
  				    (".hqx" . "x-hqx")
  				    (".Z"  . "x-compress")
! 				    (".bz2"  . "x-bzip2")
! 				    (".xz"  . "x-xz"))
    "An alist of file extensions and appropriate content-transfer-encodings."
    :type '(repeat (cons :format "%v"
  		       (string :tag "Extension")

bug#11839: teach some url code about .xz files

[Glenn Morris]

Liam Stitt wrote:

> Hi.  The code in lisp/url knows about .gz and .bz2 files, but not about the
> more recent .xz variety.  These two trivial patches correct this:

Thanks. This seems reasonable, but I have no idea what this code is for
(url-file-find-possibly-compressed-file etc), so I cannot test this.
Can you give an example of how it can be used?

Also, doesn't this line of url-file:

(setq uncompressed-filename
   (if (string-match "\\.\\(gz\\|Z\\|z\\)$"  filename)
                    (substring filename 0 (match-beginning 0)) filename))
need bz2 etc adding?

(Also I feel like lists of compressed file extensions are being
replicated in several places in Emacs: here in url-file,
dired-compress-file-suffixes, jka-compr-compression-info-list,
ibuffer-compressed-file-name-regexp, tags-compression-info-list, ...)

bug#11839: teach some url code about .xz files

[Chong Yidong]

stittl@cuug.ab.ca (Liam Stitt) writes:

> Hi.  The code in lisp/url knows about .gz and .bz2 files, but not
> about the more recent .xz variety.  These two trivial patches correct
> this:

Thanks, committed.