Commit graph

9 commits

Author SHA1 Message Date
Junio C Hamano
f258475a6e Per-path attribute based hunk header selection.
This makes"diff -p" hunk headers customizable via gitattributes mechanism.
It is based on Johannes's earlier patch that allowed to define a single
regexp to be used for everything.

The mechanism to arrive at the regexp that is used to define hunk header
is the same as other use of gitattributes.  You assign an attribute, funcname
(because "diff -p" typically uses the name of the function the patch is about
as the hunk header), a simple string value.  This can be one of the names of
built-in pattern (currently, "java" is defined) or a custom pattern name, to
be looked up from the configuration file.

  (in .gitattributes)
  *.java   funcname=java
  *.perl   funcname=perl

  (in .git/config)
  [funcname]
    java = ... # ugly and complicated regexp to override the built-in one.
    perl = ... # another ugly and complicated regexp to define a new one.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-07-06 01:20:47 -07:00
Pierre Habouzit
52fae7de4e Missing statics.
Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-08 02:37:19 -07:00
Junio C Hamano
a6080a0a44 War on whitespace
This uses "git-apply --whitespace=strip" to fix whitespace errors that have
crept in to our source files over time.  There are a few files that need
to have trailing whitespaces (most notably, test vectors).  The results
still passes the test, and build result in Documentation/ area is unchanged.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2007-06-07 00:04:01 -07:00
Andy Parkins
f73da29fa2 Increase length of function name buffer
In xemit.c:xdl_emit_diff() a buffer for showing the function name as
commentary is allocated; this buffer was 40 characters.  This is a bit
small; particularly for C++ function names where there is often an
identical prefix (like void LongNamespace::LongClassName) on multiple
functions, which makes the context the same everywhere.  In other words
the context is useless.  This patch increases that buffer to 80
characters - which may still not be enough, but is better

Signed-off-by: Andy Parkins <andyparkins@gmail.com>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-11-23 22:51:41 -08:00
Petr Baudis
70da769a46 xdiff: Match GNU diff behaviour when deciding hunk comment worthiness of lines
This removes the '#' and '(' tests and adds a '$' test instead although I have
no idea what it is actually good for - but hey, if that's what GNU diff does...

Pasky only went and did as Junio sayeth.

Signed-off-by: Petr Baudis <pasky@suse.cz>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-10-25 12:57:33 -07:00
Jim Meyering
67aef03455 xdiff/xemit.c (xdl_find_func): Elide trailing white space in a context header.
This removes trailing blanks from git-generated diff headers
the same way a similar patch did that for GNU diff:

  http://article.gmane.org/gmane.comp.gnu.utils.bugs/13839

That is, it removes trailing blanks on the hunk header line that
shows the function name.

Signed-off-by: Jim Meyering <jim@meyering.net>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-10-23 14:33:54 -07:00
Linus Torvalds
a9ed376b15 xdiff: generate "anti-diffs" aka what is common to two files
This fairly trivial patch adds a new XDL_EMIT_xxx flag to tell libxdiff
that we don't want to generate the _diff_ between two files, we want to
see the lines that are _common_ to two files.

So when you set XDL_EMIT_COMMON, xdl_diff() will do everything exactly
like it used to do, but the output records it generates just contain the
lines that aren't part of the diff.

This is for doing things like generating the common base case for a file
that was added in both branches.

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-06-28 22:24:32 -07:00
Mark Wooding
acb7257729 xdiff: Show function names in hunk headers.
The speed of the built-in diff generator is nice; but the function names
shown by `diff -p' are /really/ nice.  And I hate having to choose.  So,
we hack xdiff to find the function names and print them.

xdiff has grown a flag to say whether to dig up the function names.  The
builtin_diff function passes this flag unconditionally.  I suppose it
could parse GIT_DIFF_OPTS, but it doesn't at the moment.  I've also
reintroduced the `function name' into the test suite, from which it was
removed in commit 3ce8f089.

The function names are parsed by a particularly stupid algorithm at the
moment: it just tries to find a line in the `old' file, from before the
start of the hunk, whose first character looks plausible.  Still, it's
most definitely a start.

Signed-off-by: Mark Wooding <mdw@distorted.org.uk>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-03-27 18:43:51 -08:00
Linus Torvalds
3443546f6e Use a *real* built-in diff generator
This uses a simplified libxdiff setup to generate unified diffs _without_
doing  fork/execve of GNU "diff".

This has several huge advantages, for example:

Before:

	[torvalds@g5 linux]$ time git diff v2.6.16.. > /dev/null

	real    0m24.818s
	user    0m13.332s
	sys     0m8.664s

After:

	[torvalds@g5 linux]$ time git diff v2.6.16.. > /dev/null

	real    0m4.563s
	user    0m2.944s
	sys     0m1.580s

and the fact that this should be a lot more portable (ie we can ignore all
the issues with doing fork/execve under Windows).

Perhaps even more importantly, this allows us to do diffs without actually
ever writing out the git file contents to a temporary file (and without
any of the shell quoting issues on filenames etc etc).

NOTE! THIS PATCH DOES NOT DO THAT OPTIMIZATION YET! I was lazy, and the
current "diff-core" code actually will always write the temp-files,
because it used to be something that you simply had to do. So this current
one actually writes a temp-file like before, and then reads it into memory
again just to do the diff. Stupid.

But if this basic infrastructure is accepted, we can start switching over
diff-core to not write temp-files, which should speed things up even
further, especially when doing big tree-to-tree diffs.

Now, in the interest of full disclosure, I should also point out a few
downsides:

 - the libxdiff algorithm is different, and I bet GNU diff has gotten a
   lot more testing. And the thing is, generating a diff is not an exact
   science - you can get two different diffs (and you will), and they can
   both be perfectly valid. So it's not possible to "validate" the
   libxdiff output by just comparing it against GNU diff.

 - GNU diff does some nice eye-candy, like trying to figure out what the
   last function was, and adding that information to the "@@ .." line.
   libxdiff doesn't do that.

 - The libxdiff thing has some known deficiencies. In particular, it gets
   the "\No newline at end of file" case wrong. So this is currently for
   the experimental branch only. I hope Davide will help fix it.

That said, I think the huge performance advantage, and the fact that it
integrates better is definitely worth it. But it should go into a
development branch at least due to the missing newline issue.

Technical note: this is based on libxdiff-0.17, but I did some surgery to
get rid of the extraneous fat - stuff that git doesn't need, and seriously
cutting down on mmfile_t, which had much more capabilities than the diff
algorithm either needed or used. In this version, "mmfile_t" is just a
trivial <pointer,length> tuple.

That said, I tried to keep the differences to simple removals, so that you
can do a diff between this and the libxdiff origin, and you'll basically
see just things getting deleted. Even the mmfile_t simplifications are
left in a state where the diffs should be readable.

Apologies to Davide, whom I'd love to get feedback on this all from (I
wrote my own "fill_mmfile()" for the new simpler mmfile_t format: the old
complex format had a helper function for that, but I did my surgery with
the goal in mind that eventually we _should_ just do

	mmfile_t mf;

	buf = read_sha1_file(sha1, type, &size);
	mf->ptr = buf;
	mf->size = size;
	.. use "mf" directly ..

which was really a nightmare with the old "helpful" mmfile_t, and really
is that easy with the new cut-down interfaces).

[ Btw, as any hawk-eye can see from the diff, this was actually generated
  with itself, so it is "self-hosting". That's about all the testing it
  has gotten, along with the above kernel diff, which eye-balls correctly,
  but shows the newline issue when you double-check it with "git-apply" ]

Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Signed-off-by: Junio C Hamano <junkio@cox.net>
2006-03-25 16:49:58 -08:00