bug#35420: Support git in ediff-patch-file

bug#35420: Support git in ediff-patch-file

[Juri Linkov]

[-- Attachment #1: Type: text/plain, Size: 62 bytes --]

This patch adds support for git patches to ediff-patch-file:


[-- Warning: decoded text below may be mangled, UTF-8 assumed --]
[-- Attachment #2: ediff-ptch.git.patch --]
[-- Type: text/x-diff, Size: 995 bytes --]

diff --git a/lisp/vc/ediff-ptch.el b/lisp/vc/ediff-ptch.el
index 4178b5a8c0..5c71c2c8cb 100644
--- a/lisp/vc/ediff-ptch.el
+++ b/lisp/vc/ediff-ptch.el
@@ -297,11 +297,15 @@ ediff-fixup-patch-map
 	      ;; file names. This is a heuristic intended to improve guessing
 	      (let ((default-directory (file-name-directory filename)))
 		(unless (or (file-name-absolute-p base-dir1)
-			    (file-name-absolute-p base-dir2)
-			    (not (file-exists-p base-dir1))
-			    (not (file-exists-p base-dir2)))
-		  (setq base-dir1 ""
-			base-dir2 "")))
+			    (file-name-absolute-p base-dir2))
+		  (if (and (file-exists-p base-dir1)
+			   (file-exists-p base-dir2))
+		      (setq base-dir1 ""
+			    base-dir2 "")
+		    (when (and (string-match-p "^a/" base-dir1)
+			       (string-match-p "^b/" base-dir2))
+		      (setq base-dir1 "a/"
+			    base-dir2 "b/")))))
 	      (or (string= (car proposed-file-names) "/dev/null")
 		  (setcar proposed-file-names
 			  (ediff-file-name-sans-prefix

bug#35420: Support git in ediff-patch-file

[Eli Zaretskii]

> From: Juri Linkov <juri@linkov.net>
> Date: Thu, 25 Apr 2019 00:38:43 +0300
> 
> +		    (when (and (string-match-p "^a/" base-dir1)
> +			       (string-match-p "^b/" base-dir2))
> +		      (setq base-dir1 "a/"
> +			    base-dir2 "b/")))))

I think I saw the file names begin with i/ and w/ instead of a/ and
b/.  Not sure when/why this happens.

bug#35420: Support git in ediff-patch-file

[Robert Pluim]

>>>>> On Thu, 25 Apr 2019 09:14:21 +0300, Eli Zaretskii <eliz@gnu.org> said:

    >> From: Juri Linkov <juri@linkov.net> Date: Thu, 25 Apr 2019
    >> 00:38:43 +0300
    >> 
    >> + (when (and (string-match-p "^a/" base-dir1) + (string-match-p
    >> "^b/" base-dir2)) + (setq base-dir1 "a/" + base-dir2 "b/")))))

    Eli> I think I saw the file names begin with i/ and w/ instead of
    Eli> a/ and b/.  Not sure when/why this happens.

You get i/, w/ and/or c/ when you run 'git diff' inside your working
tree, depending on whether the changed file is in the 'i'ndex,
'w'orking tree, or 'c'ache (also known as the staging area). Things
like 'git format-patch' and 'git show' use a/ and b/ by default.

And of course, since this is git, you can tell it to use other
prefixes using '--src-prefix' and '--dst-prefix'.

Robert

bug#35420: Support git in ediff-patch-file

[Eli Zaretskii]

> From: Robert Pluim <rpluim@gmail.com>
> Cc: Juri Linkov <juri@linkov.net>,  35420@debbugs.gnu.org
> Date: Thu, 25 Apr 2019 09:53:16 +0200
> 
> You get i/, w/ and/or c/ when you run 'git diff' inside your working
> tree, depending on whether the changed file is in the 'i'ndex,
> 'w'orking tree, or 'c'ache (also known as the staging area). Things
> like 'git format-patch' and 'git show' use a/ and b/ by default.
> 
> And of course, since this is git, you can tell it to use other
> prefixes using '--src-prefix' and '--dst-prefix'.

Thanks.  I guess we'd like to support these use cases as well, right?

Also, what's the situation with hg?  Is it similar?

bug#35420: Support git in ediff-patch-file

[Robert Pluim]

>>>>> On Thu, 25 Apr 2019 11:46:33 +0300, Eli Zaretskii <eliz@gnu.org> said:

    >> From: Robert Pluim <rpluim@gmail.com> Cc: Juri Linkov
    >> <juri@linkov.net>, 35420@debbugs.gnu.org Date: Thu, 25 Apr 2019
    >> 09:53:16 +0200
    >> 
    >> You get i/, w/ and/or c/ when you run 'git diff' inside your
    >> working tree, depending on whether the changed file is in the
    >> 'i'ndex, 'w'orking tree, or 'c'ache (also known as the staging
    >> area). Things like 'git format-patch' and 'git show' use a/ and
    >> b/ by default.
    >> 
    >> And of course, since this is git, you can tell it to use other
    >> prefixes using '--src-prefix' and '--dst-prefix'.

    Eli> Thanks.  I guess we'd like to support these use cases as
    Eli> well, right?

Yes, that would be a good improvement.

    Eli> Also, what's the situation with hg?  Is it similar?

I donʼt use hg, but based on a quick test it uses a/ and b/

Robert

bug#35420: Support git in ediff-patch-file

[Juri Linkov]

>> You get i/, w/ and/or c/ when you run 'git diff' inside your working
>> tree, depending on whether the changed file is in the 'i'ndex,
>> 'w'orking tree, or 'c'ache (also known as the staging area). Things
>> like 'git format-patch' and 'git show' use a/ and b/ by default.
>> 
>> And of course, since this is git, you can tell it to use other
>> prefixes using '--src-prefix' and '--dst-prefix'.
>
> Thanks.  I guess we'd like to support these use cases as well, right?

I implemented support for these cases as well and pushed to master.