bug#66212: 30.0.50; C-x v v and vc-diff with fossil-scm

bug#66212: 30.0.50; C-x v v and vc-diff with fossil-scm

[Alfred M. Szmidt]

When trying to use C-x v v in a vc-diff buffer, and when the version
control system is Fossil (this is using GNU patch):

Checking in foo...
user-error: Patch failed: can't find file to patch at input line 5
Perhaps you used the wrong -p or --strip option?
The text leading up to this was:
--------------------------
|Index: foo
|==================================================================
|--- foo
|+++ foo
--------------------------
File to patch: 
Skip this patch? [y] 
Skipping patch.
1 out of 1 hunk ignored


To reproduce, make a empty Fossil repostiroy, add and commit a file,
add a line, C-x v =, C-x v v.  vc-fossil has to be installed.


In GNU Emacs 30.0.50 (build 3, x86_64-unknown-openbsd7.3, GTK+ Version
 3.24.37, cairo version 1.17.8) of 2023-09-25 built on
 nitrogenium.mendeleev
Repository revision: df5a9a78b51f2f42d2dbb010e811a239fc014732
Repository branch: master
System Description: OpenBSD nitrogenium.mendeleev 7.3 GENERIC.MP#3 amd64

Configured features:
CAIRO DBUS FREETYPE GIF GLIB GNUTLS GSETTINGS HARFBUZZ JPEG JSON LCMS2
LIBOTF LIBXML2 M17N_FLT MODULES NOTIFY KQUEUE PDUMPER PNG RSVG THREADS
TIFF TOOLKIT_SCROLL_BARS WEBP X11 XDBE XIM XINPUT2 XPM GTK3 ZLIB

Important settings:
  locale-coding-system: nil

Major mode: Fundamental

Minor modes in effect:
  global-company-mode: t
  company-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  minibuffer-regexp-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
~/vc-backup hides /home/ams/.emacs.d/elpa/vc-backup-1.1.0/vc-backup
~/loaddefs hides /home/ams/emacs/lisp/loaddefs

Features:
(shadow emacsbug message yank-media puny dired dired-loaddefs rfc822
mml mml-sec epa epg rfc6068 epg-config gnus-util mm-decode mm-bodies
mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader vc-fossil
vc vc-dispatcher term/screen term/xterm xterm rcirc parse-time iso8601
time-date mail-queue sendmail rfc2047 rfc2045 ietf-drums mm-util
mail-prsvr mail-utils slime-asdf grep slime-quicklisp slime-fancy
slime-indentation slime-cl-indent cl-indent slime-trace-dialog
slime-fontifying-fu slime-package-fu slime-references
slime-compiler-notes-tree slime-scratch slime-presentations advice
bridge slime-macrostep macrostep slime-mdot-fu slime-enclosing-context
slime-fuzzy slime-fancy-trace slime-fancy-inspector slime-c-p-c
slime-editing-commands slime-autodoc slime-repl elp slime-parse slime
derived cl-extra help-mode easy-mmode gud apropos compile
text-property-search arc-mode archive-mode noutline outline icons pp
comint ansi-osc ansi-color hyperspec thingatpt slime-autoloads
company-oddmuse company-keywords company-etags etags fileloop
generator xref project ring company-gtags company-dabbrev-code
company-dabbrev company-files company-capf company-cmake company-xcode
company-clang company-semantic company-eclim company-template
company-bbdb company edmacro kmacro pcase cal-menu calendar
cal-loaddefs autoload loaddefs-gen radix-tree lisp-mnt finder-inf
disp-table vc-backup-autoloads package browse-url url url-proxy
url-privacy url-expand url-methods url-history url-cookie
generate-lisp-file url-domsuf url-util mailcap url-handlers url-parse
auth-source cl-seq eieio eieio-core cl-macs password-cache json subr-x
map byte-opt gv bytecomp byte-compile url-vars cl-loaddefs cl-lib rmc
iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook
vc-hooks lisp-float-type elisp-mode mwheel term/x-win x-win
term/common-win x-dnd touch-screen tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode
lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch
easymenu timer select scroll-bar mouse jit-lock font-lock syntax
font-core term/tty-colors frame minibuffer nadvice seq simple
cl-generic indonesian philippine cham georgian utf-8-lang misc-lang
vietnamese tibetan thai tai-viet lao korean japanese eucjp-ms cp51932
hebrew greek romanian slovak czech european ethiopic indian cyrillic
chinese composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button
loaddefs theme-loaddefs faces cus-face macroexp files window
text-properties overlay sha1 md5 base64 format env code-pages mule
custom widget keymap hashtable-print-readable backquote threads
dbusbind kqueue lcms2 dynamic-setting system-font-setting
font-render-setting cairo gtk x-toolkit xinput2 x multi-tty
move-toolbar make-network-process emacs)

Memory information:
((conses 16 214273 12959) (symbols 48 16544 0) (strings 32 53834 633)
 (string-bytes 1 1487984) (vectors 16 21835)
 (vector-slots 8 257553 8908) (floats 8 63 323) (intervals 56 279 0)
 (buffers 984 11))

bug#66212: 30.0.50; C-x v v and vc-diff with fossil-scm

[Dmitry Gutov]

On 26/09/2023 15:25, Alfred M. Szmidt wrote:
> When trying to use C-x v v in a vc-diff buffer, and when the version
> control system is Fossil (this is using GNU patch):
> 
> Checking in foo...
> user-error: Patch failed: can't find file to patch at input line 5
> Perhaps you used the wrong -p or --strip option?
> The text leading up to this was:
> --------------------------
> |Index: foo
> |==================================================================
> |--- foo
> |+++ foo
> --------------------------
> File to patch:
> Skip this patch? [y]
> Skipping patch.
> 1 out of 1 hunk ignored
> 
> 
> To reproduce, make a empty Fossil repostiroy, add and commit a file,
> add a line, C-x v =, C-x v v.  vc-fossil has to be installed.

Could you do some more investigation?

Is it just that 'patch' is unable to recognize the format of the diff 
file? Or is it launched from the wrong directory? With wrong arguments?

bug#66212: 30.0.50; C-x v v and vc-diff with fossil-scm

[Eli Zaretskii]

> From: "Alfred M. Szmidt" <ams@gnu.org>
> Date: Tue, 26 Sep 2023 08:25:01 -0400
> 
> 
> When trying to use C-x v v in a vc-diff buffer, and when the version
> control system is Fossil (this is using GNU patch):
> 
> Checking in foo...
> user-error: Patch failed: can't find file to patch at input line 5
> Perhaps you used the wrong -p or --strip option?
> The text leading up to this was:
> --------------------------
> |Index: foo
> |==================================================================
> |--- foo
> |+++ foo
> --------------------------
> File to patch: 
> Skip this patch? [y] 
> Skipping patch.
> 1 out of 1 hunk ignored
> 
> 
> To reproduce, make a empty Fossil repostiroy, add and commit a file,
> add a line, C-x v =, C-x v v.  vc-fossil has to be installed.

Crystal ball says that vc-fossil (which is not part of Emacs, AFAICT)
either doesn't instruct Fossil to produce root-relative file names in
the diffs (IOW, "foo" above should actually ne "some/directory/foo"),
or doesn't set the default-directory of the vc-diff buffer to the
directory of the files as named in the diffs.

bug#66212: 30.0.50; C-x v v and vc-diff with fossil-scm

[Alfred M. Szmidt]

   > From: "Alfred M. Szmidt" <ams@gnu.org>
   > Date: Tue, 26 Sep 2023 08:25:01 -0400
   > 
   > 
   > When trying to use C-x v v in a vc-diff buffer, and when the version
   > control system is Fossil (this is using GNU patch):
   > 
   > Checking in foo...
   > user-error: Patch failed: can't find file to patch at input line 5
   > Perhaps you used the wrong -p or --strip option?
   > The text leading up to this was:
   > --------------------------
   > |Index: foo
   > |==================================================================
   > |--- foo
   > |+++ foo
   > --------------------------
   > File to patch: 
   > Skip this patch? [y] 
   > Skipping patch.
   > 1 out of 1 hunk ignored
   > 
   > 
   > To reproduce, make a empty Fossil repostiroy, add and commit a file,
   > add a line, C-x v =, C-x v v.  vc-fossil has to be installed.

   Crystal ball says that vc-fossil (which is not part of Emacs, AFAICT)
   either doesn't instruct Fossil to produce root-relative file names in
   the diffs (IOW, "foo" above should actually ne "some/directory/foo"),

The file foo was in ./ -- so I think the above is correct.

   or doesn't set the default-directory of the vc-diff buffer to the
   directory of the files as named in the diffs.

I'll check that.