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Author SHA1 Message Date
Johan Herland
2ff3a80334 Teach --dirstat not to completely ignore rearranged lines within a file
Currently, the --dirstat analysis ignores when lines within a file are
rearranged, because the "damage" calculated by show_dirstat() is 0.
However, if the object name has changed, we already know that there is
some damage, and it is unintuitive to claim there is _no_ damage.

Teach show_dirstat() to assign a minimum amount of damage (== 1) to
entries for which the analysis otherwise yields zero damage, to still
represent that these files are changed, instead of saying that there
is no change.

Also, skip --dirstat analysis when the object names are the same (e.g. for
a pure file rename).

Signed-off-by: Johan Herland <johan@herland.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-04-11 11:16:15 -07:00
Johan Herland
0133dab75d --dirstat-by-file: Make it faster and more correct
Currently, when using --dirstat-by-file, it first does the full --dirstat
analysis (using diffcore_count_changes()), and then resets 'damage' to 1,
if any damage was found by diffcore_count_changes().

But --dirstat-by-file is not interested in the file damage per se. It only
cares if the file changed at all. In that sense it only cares if the blob
object for a file has changed. We therefore only need to compare the
object names of each file pair in the diff queue and we can skip the
entire --dirstat analysis and simply set 'damage' to 1 for each entry
where the object name has changed.

This makes --dirstat-by-file faster, and also bypasses --dirstat's practice
of ignoring rearranged lines within a file.

The patch also contains an added testcase verifying that --dirstat-by-file
now detects changes that only rearrange lines within a file.

Signed-off-by: Johan Herland <johan@herland.net>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-04-11 10:12:24 -07:00
Junio C Hamano
467ddc14fe git diff -D: omit the preimage of deletes
When reviewing a patch while concentrating primarily on the text after
then change, wading through pages of deleted text involves a cognitive
burden.

Introduce the -D option that omits the preimage text from the patch output
for deleted files.  When used with -B (represent total rewrite as a single
wholesale deletion followed by a single wholesale addition), the preimage
text is also omitted.

To prevent such a patch from being applied by mistake, the output is
designed not to be usable by "git apply" (or GNU "patch"); it is strictly
for human consumption.

It of course is possible to "apply" such a patch by hand, as a human can
read the intention out of such a patch.  It however is impossible to apply
such a patch even manually in reverse, as the whole point of this option
is to omit the information necessary to do so from the output.

Initial request by Mart Sõmermaa, documentation and tests helped by
Michael J Gruber.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-04-02 23:52:20 -07:00
Junio C Hamano
f31027c99c diffcore-rename: fall back to -C when -C -C busts the rename limit
When there are too many paths in the project, the number of rename source
candidates "git diff -C -C" finds will exceed the rename detection limit,
and no inexact rename detection is performed.  We however could fall back
to "git diff -C" if the number of modified paths is sufficiently small.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-22 14:29:07 -07:00
Johannes Schindelin
c0aa335c95 Remove unused variables
Noticed by gcc 4.6.0.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-22 11:43:27 -07:00
Stephen Boyd
c2e86addb8 Fix sparse warnings
Fix warnings from 'make check'.

 - These files don't include 'builtin.h' causing sparse to complain that
   cmd_* isn't declared:

   builtin/clone.c:364, builtin/fetch-pack.c:797,
   builtin/fmt-merge-msg.c:34, builtin/hash-object.c:78,
   builtin/merge-index.c:69, builtin/merge-recursive.c:22
   builtin/merge-tree.c:341, builtin/mktag.c:156, builtin/notes.c:426
   builtin/notes.c:822, builtin/pack-redundant.c:596,
   builtin/pack-refs.c:10, builtin/patch-id.c:60, builtin/patch-id.c:149,
   builtin/remote.c:1512, builtin/remote-ext.c:240,
   builtin/remote-fd.c:53, builtin/reset.c:236, builtin/send-pack.c:384,
   builtin/unpack-file.c:25, builtin/var.c:75

 - These files have symbols which should be marked static since they're
   only file scope:

   submodule.c:12, diff.c:631, replace_object.c:92, submodule.c:13,
   submodule.c:14, trace.c:78, transport.c:195, transport-helper.c:79,
   unpack-trees.c:19, url.c:3, url.c:18, url.c:104, url.c:117, url.c:123,
   url.c:129, url.c:136, thread-utils.c:21, thread-utils.c:48

 - These files redeclare symbols to be different types:

   builtin/index-pack.c:210, parse-options.c:564, parse-options.c:571,
   usage.c:49, usage.c:58, usage.c:63, usage.c:72

 - These files use a literal integer 0 when they really should use a NULL
   pointer:

   daemon.c:663, fast-import.c:2942, imap-send.c:1072, notes-merge.c:362

While we're in the area, clean up some unused #includes in builtin files
(mostly exec_cmd.h).

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-22 10:16:54 -07:00
Junio C Hamano
0ce6a51b43 Merge branch 'jk/merge-rename-ux'
* jk/merge-rename-ux:
  pull: propagate --progress to merge
  merge: enable progress reporting for rename detection
  add inexact rename detection progress infrastructure
  commit: stop setting rename limit
  bump rename limit defaults (again)
  merge: improve inexact rename limit warning
2011-03-19 23:23:56 -07:00
Junio C Hamano
4e530c5049 Merge branch 'jk/diffstat-binary' into maint
* jk/diffstat-binary:
  diff: don't retrieve binary blobs for diffstat
  diff: handle diffstat of rewritten binary files
2011-03-16 16:47:26 -07:00
Jonathan Nieder
9cba13ca5d standardize brace placement in struct definitions
In a struct definitions, unlike functions, the prevailing style is for
the opening brace to go on the same line as the struct name, like so:

 struct foo {
	int bar;
	char *baz;
 };

Indeed, grepping for 'struct [a-z_]* {$' yields about 5 times as many
matches as 'struct [a-z_]*$'.

Linus sayeth:

 Heretic people all over the world have claimed that this inconsistency
 is ...  well ...  inconsistent, but all right-thinking people know that
 (a) K&R are _right_ and (b) K&R are right.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-03-16 12:49:02 -07:00
Jeff King
abb371a1ef diff: don't retrieve binary blobs for diffstat
We only need the size, which is much cheaper to get,
especially if it is a big binary file.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-22 10:58:18 -08:00
Jeff King
ded0abc73c diff: handle diffstat of rewritten binary files
The logic in builtin_diffstat assumes that a
complete_rewrite pair should have its lines counted. This is
nonsensical for binary files and leads to confusing things
like:

  $ git diff --stat --summary HEAD^ HEAD
   foo.rand |  Bin 4096 -> 4096 bytes
   1 files changed, 0 insertions(+), 0 deletions(-)

  $ git diff --stat --summary -B HEAD^ HEAD
   foo.rand |   34 +++++++++++++++-------------------
   1 files changed, 15 insertions(+), 19 deletions(-)
   rewrite foo.rand (100%)

So let's reorder the function to handle binary files first
(which from diffstat's perspective look like complete
rewrites anyway), then rewrites, then actual diffstats.

There are two bonus prizes to this reorder:

  1. It gets rid of a now-superfluous goto.

  2. The binary case is at the top, which means we can
     further optimize it in the next patch.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-22 10:57:58 -08:00
Jeff King
92c57e5c1d bump rename limit defaults (again)
We did this once before in 5070591 (bump rename limit
defaults, 2008-04-30). Back then, we were shooting for about
1 second for a diff/log calculation, and 5 seconds for a
merge.

There are a few new things to consider, though:

  1. Average processors are faster now.

  2. We've seen on the mailing list some ugly merges where
     not using inexact rename detection leads to many more
     conflicts. Merges of this size take a long time
     anyway, so users are probably happy to spend a little
     bit of time computing the renames.

Let's bump the diff/merge default limits from 200/500 to
400/1000. Those are 2 seconds and 10 seconds respectively on
my modern hardware.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-02-21 10:23:36 -08:00
Junio C Hamano
6ae7a51a2e Merge branch 'ks/blame-worktree-textconv-cached'
* ks/blame-worktree-textconv-cached:
  fill_textconv(): Don't get/put cache if sha1 is not valid
  t/t8006: Demonstrate blame is broken when cachetextconv is on
2010-12-21 14:30:52 -08:00
Kirill Smelkov
9ec09b0495 fill_textconv(): Don't get/put cache if sha1 is not valid
When blaming files in the working tree, the filespec is marked with
!sha1_valid, as we have not given the contents an object name yet.  The
function to cache textconv results (keyed on the object name), however,
didn't check this condition, and ended up on storing the cached result
under a random object name.

Cc: Axel Bonnet <axel.bonnet@ensimag.imag.fr>
Cc: Clément Poulain <clement.poulain@ensimag.imag.fr>
Cc: Diane Gasselin <diane.gasselin@ensimag.imag.fr>
Cc: Jeff King <peff@peff.net>
Signed-off-by: Kirill Smelkov <kirr@landau.phys.spbu.ru>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-19 18:41:32 -08:00
Junio C Hamano
cf7a64b54a Merge branch 'kb/diff-C-M-synonym'
* kb/diff-C-M-synonym:
  diff: use "find" instead of "detect" as prefix for long forms of -M and -C
  diff: add --detect-copies-harder as a synonym for --find-copies-harder
2010-12-16 12:58:59 -08:00
Yann Dirson
f611ddc774 diff: use "find" instead of "detect" as prefix for long forms of -M and -C
It is more consistent with existing --find-copies-harder; luckily "detect"
variant has not appeared in any officially released version of git.

Signed-off-by: Yann Dirson <ydirson@altern.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-10 13:52:05 -08:00
Junio C Hamano
8577def6fc Merge branch 'np/diff-in-corrupt-repository' into maint
* np/diff-in-corrupt-repository:
  diff: don't presume empty file when corresponding object is missing
2010-12-09 10:36:39 -08:00
Junio C Hamano
ae0a37cd6b Merge branch 'cm/diff-check-at-eol' into maint
* cm/diff-check-at-eol:
  diff --check: correct line numbers of new blank lines at EOF
2010-12-09 10:36:10 -08:00
Junio C Hamano
f04aa35eb6 Merge branch 'jk/diff-CBM'
* jk/diff-CBM:
  diff: report bogus input to -C/-M/-B
2010-12-08 11:24:11 -08:00
Junio C Hamano
f5a5531e4e Merge branch 'np/diff-in-corrupt-repository'
* np/diff-in-corrupt-repository:
  diff: don't presume empty file when corresponding object is missing
2010-11-29 17:52:33 -08:00
Junio C Hamano
039e84e30d Merge branch 'cm/diff-check-at-eol'
* cm/diff-check-at-eol:
  diff --check: correct line numbers of new blank lines at EOF
2010-11-29 17:52:31 -08:00
Kevin Ballard
150a5daad0 diff: add --detect-copies-harder as a synonym for --find-copies-harder
Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-29 16:58:27 -08:00
Junio C Hamano
9cffe2018a Merge branch 'cb/diff-fname-optim' into maint
* cb/diff-fname-optim:
  diff: avoid repeated scanning while looking for funcname
  do not search functions for patch ID
  add rebase patch id tests
2010-11-24 12:46:26 -08:00
Junio C Hamano
78bce6c7e9 Merge branch 'jk/no-textconv-symlink' into maint
* jk/no-textconv-symlink:
  diff: don't use pathname-based diff drivers for symlinks
2010-11-24 12:46:20 -08:00
Junio C Hamano
8cf666c9ee Merge branch 'cb/diff-fname-optim'
* cb/diff-fname-optim:
  diff: avoid repeated scanning while looking for funcname
  do not search functions for patch ID
  add rebase patch id tests
2010-11-17 14:59:16 -08:00
Junio C Hamano
6a2e93f107 Merge branch 'jk/no-textconv-symlink'
* jk/no-textconv-symlink:
  diff: don't use pathname-based diff drivers for symlinks
2010-11-17 14:59:10 -08:00
Junio C Hamano
329351feeb Merge branch 'kb/merge-recursive-rename-threshold'
* kb/merge-recursive-rename-threshold:
  diff: add synonyms for -M, -C, -B
  merge-recursive: option to specify rename threshold

Conflicts:
	Documentation/diff-options.txt
	Documentation/merge-strategies.txt
2010-10-26 21:54:04 -07:00
Junio C Hamano
d7806967bd Merge branch 'maint'
* maint:
  Fix copy-pasted comments related to tree diff handling.
2010-10-26 15:04:05 -07:00
Yann Dirson
c3fced6498 Fix copy-pasted comments related to tree diff handling.
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-25 00:21:56 -07:00
Nicolas Pitre
c50c4316e1 diff: don't presume empty file when corresponding object is missing
The low-level diff code will happily produce totally bogus diff output
with a broken repository via format-patch and friends by treating missing
objects as empty files.  Let's prevent that from happening any longer.

Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Nicolas Pitre <nico@fluxnic.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-21 22:23:34 -07:00
Jeff King
07cd726527 diff: report bogus input to -C/-M/-B
We already detect invalid input to these functions, but we
simply exit with an error code, never saying anything as
simple as "your input was wrong". Let's fix that.

Before:

  $ git diff -CM
  $ echo $?
  128

After:

  $ git diff -CM
  error: invalid argument to -C: M
  $ echo $?
  128

There should be no problems with having diff_opt_parse print
to stderr, as there is already precedent in complaining
about bogus --color and --output arguments.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-21 15:44:53 -07:00
Christoph Mallon
8837d33595 diff --check: correct line numbers of new blank lines at EOF
The whitespace check printed the value of the wrong variable, i.e. the
beginning of the block of blank lines at the EOF (possibly absent) in the
old file.

As "git diff --check" is used by users to check their changes before
making a commit, we should point at the line number in the file after
the change.

Signed-off-by: Christoph Mallon <christoph.mallon@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-16 18:57:35 -07:00
Junio C Hamano
b3c16ee454 Merge branch 'jc/pickaxe-grep'
* jc/pickaxe-grep:
  diff/log -G<pattern>: tests
  git log/diff: add -G<regexp> that greps in the patch text
  diff: pass the entire diff-options to diffcore_pickaxe()
  gitdiffcore doc: update pickaxe description
2010-09-29 13:49:03 -07:00
Matthieu Moy
9ec26eb7cd diff: trivial fix for --output file error message
The option argument is either after the equal sign in --output=... or in
the next command-line argument. optarg is the reliable way to access it.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-29 13:25:17 -07:00
Kevin Ballard
37ab5156ae diff: add synonyms for -M, -C, -B
Add new long-form options --detect-renames[=<n>], --detect-copies[=<n>],
and --break-rewrites[=[<n>][/<m>]] as synonyms for the -M, -C, and -B
options (respectively).

Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-29 13:18:04 -07:00
Kevin Ballard
10ae7526be merge-recursive: option to specify rename threshold
The recursive merge strategy turns on rename detection but leaves the
rename threshold at the default. Add a strategy option to allow the user
to specify a rename threshold to use.

Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-29 13:15:56 -07:00
Clemens Buchacher
ad14b450c0 do not search functions for patch ID
Visual aids, such as the function name in the hunk
header, are not necessary for the purposes of
computing a patch ID.

This is a performance optimization.

Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-23 18:35:07 -07:00
Jeff King
d391c0ff94 diff: don't use pathname-based diff drivers for symlinks
When we're diffing symlinks, we consider the contents to be
the pathname that the symlink points to. When a user sets up
a userdiff driver like "*.pdf diff=pdf", their "diff.pdf.*"
config generally tells us what to do with the content of
pdf files.

With the current code, we will actually process a symlink
like "link.pdf" using a configured pdf driver, meaning we
are using contents which consist of a pathname with
configuration that is expecting contents that consist of an
actual pdf file.

The most noticeable example of this would have been
textconv; however, it was already protected in its own
textconv-specific code path. We can still see the breakage
with something like "diff.*.binary", though. You could
also see it with diff.*.funcname, though it is a bit harder
to trigger accidentally there.

This patch adds a check for S_ISREG lower in the callstack
than the textconv-specific check, which should block use of
any userdiff config for non-regular files. We can drop the
check in the textconv code, which is now redundant.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-23 18:32:32 -07:00
Junio C Hamano
8ac8cf5bc1 Merge branch 'maint'
* maint:
  xdiff-interface.c: always trim trailing space from xfuncname matches
  diff.c: call regfree to free memory allocated by regcomp when necessary
2010-09-09 17:29:40 -07:00
Brandon Casey
ef5644ea6e diff.c: call regfree to free memory allocated by regcomp when necessary
Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-09 17:18:04 -07:00
Junio C Hamano
7cc1e385a0 Merge branch 'cb/binary-patch-id'
* cb/binary-patch-id:
  hash binary sha1 into patch id
2010-08-31 16:24:48 -07:00
Junio C Hamano
f506b8e8b5 git log/diff: add -G<regexp> that greps in the patch text
Teach "-G<regexp>" that is similar to "-S<regexp> --pickaxe-regexp" to the
"git diff" family of commands.  This limits the diff queue to filepairs
whose patch text actually has an added or a deleted line that matches the
given regexp.  Unlike "-S<regexp>", changing other parts of the line that
has a substring that matches the given regexp IS counted as a change, as
such a change would appear as one deletion followed by one addition in a
patch text.

Unlike -S (pickaxe) that is intended to be used to quickly detect a commit
that changes the number of occurrences of hits between the preimage and
the postimage to serve as a part of larger toolchain, this is meant to be
used as the top-level Porcelain feature.

The implementation unfortunately has to run "diff" twice if you are
running "log" family of commands to produce patches in the final output
(e.g. "git log -p" or "git format-patch").  I think we _could_ cache the
result in-core if we wanted to, but that would require larger surgery to
the diffcore machinery (i.e. adding an extra pointer in the filepair
structure to keep a pointer to a strbuf around, stuff the textual diff to
the strbuf inside diffgrep_consume(), and make use of it in later stages
when it is available) and it may not be worth it.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-31 14:30:29 -07:00
Junio C Hamano
382f013bc4 diff: pass the entire diff-options to diffcore_pickaxe()
That would make it easier to give enhanced feature to the
pickaxe transformation.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-31 14:30:28 -07:00
Junio C Hamano
e40b34b1ec Merge branch 'mm/shortopt-detached'
* mm/shortopt-detached:
  log: parse separate option for --glob
  log: parse separate options like git log --grep foo
  diff: parse separate options --stat-width n, --stat-name-width n
  diff: split off a function for --stat-* option parsing
  diff: parse separate options like -S foo

Conflicts:
	revision.c
2010-08-21 23:28:31 -07:00
Junio C Hamano
bd3a97a27a Merge branch 'jc/maint-follow-rename-fix'
* jc/maint-follow-rename-fix:
  log: test for regression introduced in v1.7.2-rc0~103^2~2
  diff --follow: do call diffcore_std() as necessary
  diff --follow: do not waste cycles while recursing
2010-08-18 12:47:18 -07:00
Junio C Hamano
cc34bb0b02 Merge branch 'jl/submodule-ignore-diff'
* jl/submodule-ignore-diff:
  Add tests for the diff.ignoreSubmodules config option
  Add the 'diff.ignoreSubmodules' config setting
  Submodules: Use "ignore" settings from .gitmodules too for diff and status
  Submodules: Add the new "ignore" config option for diff and status

Conflicts:
	diff.c
2010-08-18 12:36:25 -07:00
Clemens Buchacher
34597c1f5a hash binary sha1 into patch id
Since commit 2f82f760 (Take binary diffs into
account for "git rebase"), binary files are
included in patch ID computation. Binary files are
diffed using the text diff algorithm, however,
which has a huge impact on performance. The
following tests performance for a 50000 line file
marked as binary in .gitattributes.

$ git format-patch --stdout --ignore-if-in-upstream master

real    0m0.367s
user    0m0.354s
sys     0m0.010s

Instead of diffing the binary files, hash the pre-
and post-image sha1, which is just as unique. As a
result, performance is much improved.

$ git format-patch --stdout --ignore-if-in-upstream master

real    0m0.016s
user    0m0.015s
sys     0m0.001s

Signed-off-by: Clemens Buchacher <drizzd@aon.at>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-16 18:31:37 -07:00
Junio C Hamano
44c48a909a diff --follow: do call diffcore_std() as necessary
Usually, diff frontends populate the output queue with filepairs without
any rename information and call diffcore_std() to sort the renames out.
When --follow is in effect, however, diff-tree family of frontend has a
hack that looks like this:

    diff-tree frontend
    -> diff_tree_sha1()
       . populate diff_queued_diff
       . if --follow is in effect and there is only one change that
         creates the target path, then
       -> try_to_follow_renames()
	  -> diff_tree_sha1() with no pathspec but with -C
	  -> diffcore_std() to find renames
	  . if rename is found, tweak diff_queued_diff and put a
	    single filepair that records the found rename there
    -> diffcore_std()
       . tweak elements on diff_queued_diff by
       - rename detection
       - path ordering
       - pickaxe filtering

We need to skip parts of the second call to diffcore_std() that is related
to rename detection, and do so only when try_to_follow_renames() did find
a rename.  Earlier 1da6175 (Make diffcore_std only can run once before a
diff_flush, 2010-05-06) tried to deal with this issue incorrectly; it
unconditionally disabled any second call to diffcore_std().

This hopefully fixes the breakage.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-13 12:17:45 -07:00
Jakub Narebski
d8faea9d18 diff: strip extra "/" when stripping prefix
There are two ways a user might want to use "diff --relative":

  1. For a file in a directory, like "subdir/file", the user
     can use "--relative=subdir/" to strip the directory.

  2. To strip part of a filename, like "foo-10", they can
     use "--relative=foo-".

We currently handle both of those situations. However, if the user passes
"--relative=subdir" (without the trailing slash), we produce inconsistent
results. For the unified diff format, we collapse the double-slash of
"a//file" correctly into "a/file". But for other formats (raw, stat,
name-status), we end up with "/file".

We can do what the user means here and strip the extra "/" (and only a
slash).  We are not hurting any existing users of (2) above with this
behavior change because the existing output for this case was nonsensical.

Patch by Jakub, tests and commit message by Jeff King.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-11 09:46:47 -07:00
Johannes Schindelin
be4f2b408e Add the 'diff.ignoreSubmodules' config setting
When you have a lot of submodules checked out, the time penalty to check
for dirty submodules can easily imply a multiplication of the total time
by the factor 20. This makes the difference between almost instantaneous
(< 2 seconds) and unbearably slow (> 50 seconds) here, since the disk
caches are constantly overloaded.

To this end, the submodule.*.ignore config option was introduced, but it
is per-submodule.

This commit introduces a global config setting to set a default
(porcelain) value for the --ignore-submodules option, keeping the
default at 'none'. It can be overridden by the submodule.*.ignore
setting and by the --ignore-submodules option.

Incidentally, this commit fixes an issue with the overriding logic:
multiple --ignore-submodules options would not clear the previously
set flags.

While at it, fix a typo in the documentation for submodule.*.ignore.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-09 09:11:50 -07:00
Jens Lehmann
aee9c7d654 Submodules: Add the new "ignore" config option for diff and status
The new "ignore" config option controls the default behavior for "git
status" and the diff family. It specifies under what circumstances they
consider submodules as modified and can be set separately for each
submodule.

The command line option "--ignore-submodules=" has been extended to accept
the new parameter "none" for both status and diff.

Users that chose submodules to get rid of long work tree scanning times
might want to set the "dirty" option for those submodules. This brings
back the pre 1.7.0 behavior, where submodule work trees were never
scanned for modifications. By using "--ignore-submodules=none" on the
command line the status and diff commands can be told to do a full scan.

This option can be set to the following values (which have the same name
and meaning as for the "--ignore-submodules" option of status and diff):

"all": All changes to the submodule will be ignored.

"dirty": Only differences of the commit recorded in the superproject and
	the submodules HEAD will be considered modifications, all changes
	to the work tree of the submodule will be ignored. When using this
	value, the submodule will not be scanned for work tree changes at
	all, leading to a performance benefit on large submodules.

"untracked": Only untracked files in the submodules work tree are ignored,
	a changed HEAD and/or modified files in the submodule will mark it
	as modified.

"none" (which is the default): Either untracked or modified files in a
	submodules work tree or a difference between the subdmodules HEAD
	and the commit recorded in the superproject will make it show up
	as changed. This value is added as a new parameter for the
	"--ignore-submodules" option of the diff family and "git status"
	so the user can override the settings in the configuration.

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-09 09:01:52 -07:00
Matthieu Moy
1e57208ef0 diff: parse separate options --stat-width n, --stat-name-width n
Part of a campaign for unstuck forms of options.

[jn: with some refactoring]

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:14:36 -07:00
Jonathan Nieder
4d7f7a4ae7 diff: split off a function for --stat-* option parsing
As an optimization, the diff_opt_parse() switchboard has
a single case for all the --stat-* options.  Split it
off into a separate function so we can enhance it
without bringing code dangerously close to the right
margin.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:14:28 -07:00
Matthieu Moy
dea007fb4c diff: parse separate options like -S foo
Change the option parsing logic in revision.c to accept separate forms
like `-S foo' in addition to `-Sfoo'. The rest of git already accepted
this form, but revision.c still used its own option parsing.

Short options affected are -S<string>, -l<num> and -O<orderfile>, for
which an empty string wouldn't make sense, hence -<option> <arg> isn't
ambiguous.

This patch does not handle --stat-name-width and --stat-width, which are
special-cases where diff_long_opt do not apply. They are handled in a
separate patch to ease review.

Original patch by Matthieu Moy, plus refactoring by Jonathan Nieder.

Signed-off-by: Matthieu Moy <Matthieu.Moy@imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-06 09:14:22 -07:00
Junio C Hamano
bb89e84f95 Merge branch 'sv/maint-diff-q-clear-fix' into maint
* sv/maint-diff-q-clear-fix:
  Fix DIFF_QUEUE_CLEAR refactoring
2010-08-03 15:17:34 -07:00
Junio C Hamano
ee38d823f7 Fix DIFF_QUEUE_CLEAR refactoring
It introduced a macro to reduce repeated assignments to three fields,
but an unrelated and incorrect change snuck in by mistake, which broke
commands like "git diff-files -p --submodule".

Noticed by Sven Verdoolaege.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-02 08:30:02 -07:00
Bo Yang
e13f38a33e diff.c: fix a graph output bug
When --graph is in effect, the line-prefix typically has colored graph
line segments and ends with reset.  The color sequence "set" given to
this function is for showing the metainfo part of the patch text and
(1) it should not be applied to the graph lines, and (2) it will be
reset at the end of line_prefix so it won't be in effect anyway.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-07-08 18:09:14 -07:00
Junio C Hamano
a76b2084fb Merge branch 'jl/status-ignore-submodules'
* jl/status-ignore-submodules:
  Add the option "--ignore-submodules" to "git status"
  git submodule: ignore dirty submodules for summary and status

Conflicts:
	builtin/commit.c
	t/t7508-status.sh
	wt-status.c
	wt-status.h
2010-06-30 11:55:39 -07:00
Junio C Hamano
e1165dd144 Merge branch 'jl/maint-diff-ignore-submodules'
* jl/maint-diff-ignore-submodules:
  t4027,4041: Use test -s to test for an empty file
  Add optional parameters to the diff option "--ignore-submodules"
  git diff: rename test that had a conflicting name
2010-06-30 11:55:37 -07:00
Junio C Hamano
4af574dbdc Merge branch 'ab/blame-textconv'
* ab/blame-textconv:
  t/t8006: test textconv support for blame
  textconv: support for blame
  textconv: make the API public

Conflicts:
	diff.h
2010-06-27 12:07:44 -07:00
Jens Lehmann
46a958b3da Add the option "--ignore-submodules" to "git status"
In some use cases it is not desirable that "git status" considers
submodules that only contain untracked content as dirty. This may happen
e.g. when the submodule is not under the developers control and not all
build generated files have been added to .gitignore by the upstream
developers. Using the "untracked" parameter for the "--ignore-submodules"
option disables checking for untracked content and lets git diff report
them as changed only when they have new commits or modified content.

Sometimes it is not wanted to have submodules show up as changed when they
just contain changes to their work tree (this was the behavior before
1.7.0). An example for that are scripts which just want to check for
submodule commits while ignoring any changes to the work tree. Also users
having large submodules known not to change might want to use this option,
as the - sometimes substantial - time it takes to scan the submodule work
tree(s) is saved when using the "dirty" parameter.

And if you want to ignore any changes to submodules, you can now do that
by using this option without parameters or with "all" (when the config
option status.submodulesummary is set, using "all" will also suppress the
output of the submodule summary).

A new function handle_ignore_submodules_arg() is introduced to parse this
option new to "git status" in a single location, as "git diff" already
knew it.

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-25 11:30:25 -07:00
Junio C Hamano
262657dce6 Merge branch 'maint'
* maint:
  Update draft release notes to 1.7.1.1
  tests: remove unnecessary '^' from 'expr' regular expression

Conflicts:
	diff.c
2010-06-22 09:35:36 -07:00
Junio C Hamano
3c656899cd Merge branch 'cc/maint-diff-CC-binary' into maint
* cc/maint-diff-CC-binary:
  diff: fix "git show -C -C" output when renaming a binary file

Conflicts:
	diff.c
2010-06-22 09:27:07 -07:00
Junio C Hamano
cb2af93ac1 Merge branch 'bw/diff-metainfo-color' into maint
* bw/diff-metainfo-color:
  diff: fix coloring of extended diff headers
2010-06-21 05:40:10 -07:00
Junio C Hamano
60335534a6 Merge branch 'rs/diff-no-minimal' into maint
* rs/diff-no-minimal:
  git diff too slow for a file
2010-06-21 05:38:50 -07:00
Junio C Hamano
5977744d04 Merge branch 'cc/maint-diff-CC-binary'
* cc/maint-diff-CC-binary:
  diff: fix "git show -C -C" output when renaming a binary file

Conflicts:
	diff.c
2010-06-18 11:16:57 -07:00
Junio C Hamano
98ad90fbab Merge branch 'by/diff-graph'
* by/diff-graph:
  Make --color-words work well with --graph
  graph.c: register a callback for graph output
  Emit a whole line in one go
  diff.c: Output the text graph padding before each diff line
  Output the graph columns at the end of the commit message
  Add a prefix output callback to diff output

Conflicts:
	diff.c
2010-06-18 11:16:57 -07:00
Junio C Hamano
18fd805583 Merge branch 'jh/diff-index-line-abbrev'
* jh/diff-index-line-abbrev:
  diff.c: Ensure "index $from..$to" line contains unambiguous SHA1s

Conflicts:
	diff.c
2010-06-18 11:16:56 -07:00
Junio C Hamano
2621ac50cc Merge branch 'ec/diff-noprefix-config'
* ec/diff-noprefix-config:
  diff: add configuration option for disabling diff prefixes.
2010-06-18 11:16:55 -07:00
Junio C Hamano
448598b508 Merge branch 'bw/diff-metainfo-color'
* bw/diff-metainfo-color:
  diff: fix coloring of extended diff headers
2010-06-13 11:21:25 -07:00
Junio C Hamano
39b5977b13 Merge branch 'rs/diff-no-minimal'
* rs/diff-no-minimal:
  git diff too slow for a file
2010-06-13 11:20:46 -07:00
Jens Lehmann
dd44d419d3 Add optional parameters to the diff option "--ignore-submodules"
In some use cases it is not desirable that the diff family considers
submodules that only contain untracked content as dirty. This may happen
e.g. when the submodule is not under the developers control and not all
build generated files have been added to .gitignore by the upstream
developers. Using the "untracked" parameter for the "--ignore-submodules"
option disables checking for untracked content and lets git diff report
them as changed only when they have new commits or modified content.

Sometimes it is not wanted to have submodules show up as changed when they
just contain changes to their work tree. An example for that are scripts
which just want to check for submodule commits while ignoring any changes
to the work tree. Also users having large submodules known not to change
might want to use this option, as the - sometimes substantial - time it
takes to scan the submodule work tree(s) is saved.

Signed-off-by: Jens Lehmann <Jens.Lehmann@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-11 13:33:17 -07:00
Axel Bonnet
a788d7d58b textconv: make the API public
The textconv functionality allows one to convert a file into text before
running diff. But this functionality can be useful to other features
such as blame.

Signed-off-by: Axel Bonnet <axel.bonnet@ensimag.imag.fr>
Signed-off-by: Clément Poulain <clement.poulain@ensimag.imag.fr>
Signed-off-by: Diane Gasselin <diane.gasselin@ensimag.imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-11 13:17:57 -07:00
Christian Couder
296c6bb21a diff: fix "git show -C -C" output when renaming a binary file
A bug was introduced in 3e97c7c6af
(No diff -b/-w output for all-whitespace changes, Nov 19 2009)
that made the lines:

  diff --git a/bar b/sub/bar
  similarity index 100%
  rename from bar
  rename to sub/bar

disappear from "git show -C -C" output when file bar is a binary
file.

Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-06-06 15:14:27 -07:00
Bo Yang
4297c0aeb5 Make --color-words work well with --graph
'--color-words' algorithm can be described as:

  1. collect a the minus/plus lines of a diff hunk, divided into
     minus-lines and plus-lines;

  2. break both minus-lines and plus-lines into words and
     place them into two mmfile_t with one word for each line;

  3. use xdiff to run diff on the two mmfile_t to get the words level diff;

And for the common parts of the both file, we output the plus side text.
diff_words->current_plus is used to trace the current position of the plus file
which printed. diff_words->last_minus is used to trace the last minus word
printed.

For '--graph' to work with '--color-words', we need to output the graph prefix
on each line of color words output. Generally, there are two conditions on
which we should output the prefix.

  1. diff_words->last_minus == 0 &&
     diff_words->current_plus == diff_words->plus.text.ptr

     that is: the plus text must start as a new line, and if there is no minus
     word printed, a graph prefix must be printed.

  2. diff_words->current_plus > diff_words->plus.text.ptr &&
     *(diff_words->current_plus - 1) == '\n'

     that is: a graph prefix must be printed following a '\n'

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-31 18:02:20 -07:00
Bo Yang
2efcc97764 Emit a whole line in one go
Since the graph prefix will be printed when calling
emit_line, so the functions should be used to emit a
complete line out once a time. No one should call
emit_line to just output some strings instead of a
complete line.
Use a strbuf to compose the whole line, and then
call emit_line to output it once.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-31 18:02:04 -07:00
Bo Yang
7be5761073 diff.c: Output the text graph padding before each diff line
Change output from diff with -p/--dirstat/--binary/--numstat/--stat/
--shortstat/--check/--summary options to align with graph paddings.

Thanks Jeff King <peff@peff.net> for reporting the '--summary' bug and
his initial patch.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-31 18:00:21 -07:00
Bo Yang
a3c158d4a5 Add a prefix output callback to diff output
The callback can be used to add some prefix string to each line of
diff output.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-31 18:00:21 -07:00
Johan Herland
3e5a188f1d diff.c: Ensure "index $from..$to" line contains unambiguous SHA1s
In the metainfo section of git diffs there's an "index" line providing
abbreviated (unless --full-index is used) blob SHA1s from the
pre-/post-images used to generate the diff. These provide hints that
can be used to reconstruct a 3-way merge when applying the patch
(see the --3way option to 'git am' for more details).

In order for this to work, however, the blob SHA1s must not be
abbreviated into ambiguity.

This patch eliminates the possible ambiguity by using find_unique_abbrev()
to produce the abbreviated SHA1s (instead of blind abbreviation by way of
"%.*s").

A testcase verifying the fix is also included.

Signed-off-by: Johan Herland <johan@herland.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-31 17:44:01 -07:00
Junio C Hamano
82c531b3b6 Merge branch 'by/log-follow'
* by/log-follow:
  tests: rename duplicate t4205
  Make git log --follow find copies among unmodified files.
  Make diffcore_std only can run once before a diff_flush
  Add a macro DIFF_QUEUE_CLEAR.
2010-05-21 04:02:23 -07:00
Junio C Hamano
1bdd46cd3a Merge branch 'tr/word-diff'
* tr/word-diff:
  diff: add --word-diff option that generalizes --color-words

Conflicts:
	diff.c
2010-05-21 04:02:17 -07:00
Bert Wesarg
374664478f diff: fix coloring of extended diff headers
Coloring the extended headers where done as a whole not per line. less with
option -R (which is the default from git) does not support this coloring
mode because of performance reasons. The -r option would be an alternative
but has problems with lines that are longer than the screen. Therefore
stick to the idiom to color each line separately. The problem is, that the
result of ill_metainfo() will also be used as an parameter to an external
diff driver, so we need to disable coloring in this case.

Because coloring is now done inside fill_metainfo() we can simply add this
string to the diff header and therefore keep the last newline in the
extended header. This results also into the fact that the external diff
driver now gets this last newline too. Which is a change in behavior
but a good one.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-19 21:06:40 -07:00
Will Palmer
1c9eecff97 diff-options: make --patch a synonym for -p
Here we simply make --patch a synonym for -p, whose mnemonic was "patch"
all along.

Signed-off-by: Will Palmer <wmpalmer@gmail.com>
Reviewed-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-18 21:50:03 -07:00
Eli Collins
f89504ddb9 diff: add configuration option for disabling diff prefixes.
With new configuration "diff.noprefix", "git diff" does not show a source or destination prefix ala "git diff --no-prefix".

Signed-off-by: Eli Collins <eli@cloudera.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-18 21:31:51 -07:00
Junio C Hamano
dd75d07899 Merge branch 'jk/cached-textconv'
* jk/cached-textconv:
  diff: avoid useless filespec population
  diff: cache textconv output
  textconv: refactor calls to run_textconv
  introduce notes-cache interface
  make commit_tree a library function
2010-05-08 22:33:08 -07:00
Bo Yang
1da6175d43 Make diffcore_std only can run once before a diff_flush
When file renames/copies detection is turned on, the
second diffcore_std will degrade a 'C' pair to a 'R' pair.

And this may happen when we run 'git log --follow' with
hard copies finding. That is, the try_to_follow_renames()
will run diffcore_std to find the copies, and then
'git log' will issue another diffcore_std, which will reduce
'src->rename_used' and recognize this copy as a rename.
This is not what we want.

So, I think we really don't need to run diffcore_std more
than one time.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-07 09:34:28 -07:00
Bo Yang
9ca5df9061 Add a macro DIFF_QUEUE_CLEAR.
Refactor the diff_queue_struct code, this macro help
to reset the structure.

Signed-off-by: Bo Yang <struggleyb.nku@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-07 09:34:27 -07:00
Junio C Hamano
6b6f5d4664 Merge branch 'maint-1.7.0' into maint
* maint-1.7.0:
  remove ecb parameter from xdi_diff_outf()
2010-05-04 15:20:47 -07:00
René Scharfe
dfea79004c remove ecb parameter from xdi_diff_outf()
xdi_diff_outf() overrides the structure members of its last parameter,
ignoring any value that callers pass in.  It's no surprise then that all
callers pass a pointer to an uninitialized structure.  They also don't
read it after the call, so the parameter is neither used for input nor
for output.   Turn it into a local variable of xdi_diff_outf().

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-04 15:19:14 -07:00
René Scharfe
582aa00bdf git diff too slow for a file
Ever since the xdiff library had been introduced to git, all its callers
have used the flag XDF_NEED_MINIMAL.  It makes sure that the smallest
possible diff is produced, but that takes quite some time if there are
lots of differences that can be expressed in multiple ways.

This flag makes a difference for only 0.1% of the non-merge commits in
the git repo of Linux, both in terms of diff size and execution time.
The patches there are mostly nice and small.

SungHyun Nam however reported a case in a different repo where a diff
took more than 20 times longer to generate with XDF_NEED_MINIMAL than
without.  Rebasing became really slow.

This patch removes this flag from all callers.  The default of xdiff is
saner because it has minimal to no impact in the normal case of small
diffs and doesn't incur that much of a speed penalty for large ones.

A follow-up patch may introduce a command line option to set the flag if
the user needs it, similar to GNU diff's -d/--minimal.

Signed-off-by: Rene Scharfe <rene.scharfe@lsrfire.ath.cx>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-02 07:59:50 -07:00
Junio C Hamano
4fd8145c0c Merge branch 'jk/maint-diffstat-overflow' into maint
* jk/maint-diffstat-overflow:
  diff: use large integers for diffstat calculations
2010-04-22 22:29:13 -07:00
Junio C Hamano
bc32d342c2 Merge branch 'jk/maint-diffstat-overflow'
* jk/maint-diffstat-overflow:
  diff: use large integers for diffstat calculations
2010-04-18 21:31:50 -07:00
Jeff King
0974c117ff diff: use large integers for diffstat calculations
The diffstat "added" and "changed" fields generally store
line counts; however, for binary files, they store file
sizes. Since we store and print these values as ints, a
diffstat on a file larger than 2G can show a negative size.
Instead, let's use uintmax_t, which should be at least 64
bits on modern platforms.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-17 11:30:21 -07:00
Thomas Rast
882749a04f diff: add --word-diff option that generalizes --color-words
This teaches the --color-words engine a more general interface that
supports two new modes:

* --word-diff=plain, inspired by the 'wdiff' utility (most similar to
  'wdiff -n <old> <new>'): uses delimiters [-removed-] and {+added+}

* --word-diff=porcelain, which generates an ad-hoc machine readable
  format:
  - each diff unit is prefixed by [-+ ] and terminated by newline as
    in unified diff
  - newlines in the input are output as a line consisting only of a
    tilde '~'

Both of these formats still support color if it is enabled, using it
to highlight the differences.  --color-words becomes a synonym for
--word-diff=color, which is the color-only format.  Also adds some
compatibility/convenience options.

Thanks to Junio C Hamano and Miles Bader for good ideas.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-14 10:56:53 -07:00
Junio C Hamano
daaf2e8892 Merge branch 'jc/conflict-marker-size' into maint
* jc/conflict-marker-size:
  diff --check: honor conflict-marker-size attribute
2010-04-09 22:38:34 -07:00
Junio C Hamano
7ec1eb93f7 Merge early parts of jk/cached-textconv 2010-04-08 23:31:51 -07:00
Junio C Hamano
aed6ca52e7 diff.c: work around pointer constness warnings
The textconv leak fix introduced two invocations of free() to release
memory pointed by "const char *", which get annoying compiler warning.
2010-04-08 23:30:49 -07:00
Junio C Hamano
3f3f8d9d09 Merge branch 'jc/conflict-marker-size'
* jc/conflict-marker-size:
  diff --check: honor conflict-marker-size attribute
2010-04-06 14:50:46 -07:00
Jeff King
b337398266 diff: avoid useless filespec population
builtin_diff calls fill_mmfile fairly early, which in turn
calls diff_populate_filespec, which actually retrieves the
file's blob contents into a buffer. Long ago, this was
sensible as we would need to look at the blobs eventually.

These days, however, we may not ever want those blobs if we
end up using a textconv cache, and for large binary files
(exactly the sort for which you might have a textconv
cache), just retrieving the objects can be costly.

This patch just pushes the fill_mmfile call a bit later, so
we can avoid populating the filespec in some cases.  There
is one thing to note that looks like a bug but isn't. We
push the fill_mmfile down into the first branch of a
conditional. It seems like we would need it on the other
branch, too, but we don't; fill_textconv does it for us (in
fact, before this, we were just writing over the results of
the fill_mmfile on that branch).

Here's a timing sample on a commit with 45 changed jpgs and
avis. The result is fully textconv cached, but we still
wasted a lot of time just pulling the blobs from storage.
The total size of the blobs (source and dest) is about
180M.

  [before]
  $ time git show >/dev/null
  real    0m0.352s
  user    0m0.148s
  sys     0m0.200s

  [after]
  $ time git show >/dev/null
  real    0m0.009s
  user    0m0.004s
  sys     0m0.004s

And that's on a warm cache. On a cold cache, the "after"
case is not much worse, but the "before" case has to do an
extra 180M of I/O.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-02 00:11:20 -07:00
Jeff King
d9bae1a178 diff: cache textconv output
Running a textconv filter can take a long time. It's
particularly bad for a large file which needs to be spooled
to disk, but even for small files, the fork+exec overhead
can add up for something like "git log -p".

This patch uses the notes-cache mechanism to keep a fast
cache of textconv output. Caches are stored in
refs/notes/textconv/$x, where $x is the userdiff driver
defined in gitattributes.

Caching is enabled only if diff.$x.cachetextconv is true.

In my test repo, on a commit with 45 jpg and avi files
changed and a textconv to show their exif tags:

  [before]
  $ time git show >/dev/null
  real    0m13.724s
  user    0m12.057s
  sys     0m1.624s

  [after, first run]
  $ git config diff.mfo.cachetextconv true
  $ time git show >/dev/null
  real    0m14.252s
  user    0m12.197s
  sys     0m1.800s

  [after, subsequent runs]
  $ time git show >/dev/null
  real    0m0.352s
  user    0m0.148s
  sys     0m0.200s

So for a slight (3.8%) cost on the first run, we achieve an
almost 40x speed up on subsequent runs.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-04-02 00:05:31 -07:00