Commit graph

39 commits

Author SHA1 Message Date
Дилян Палаузов
5d308512ff do not include the same header twice
A few files include the same header file directly more than once.

As all these headers protect themselves against repeated inclusion
by the "#ifndef FOO_H / #define FOO_H / ... / #endif" idiom, leave
only the first inclusion and remove the later inclusion as a no-op
clean-up.

Signed-off-by: Дилян Палаузов <git-dpa@aegee.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2015-02-13 13:16:12 -08:00
Johannes Sixt
8a2e8da367 userdiff: have 'cpp' hunk header pattern catch more C++ anchor points
The hunk header pattern 'cpp' is intended for C and C++ source code, but
it is actually not particularly useful for the latter, and even misses
some use-cases for the former.

The parts of the pattern have the following flaws:

- The first part matches an identifier followed immediately by a colon
  and arbitrary text and is intended to reject goto labels and C++
  access specifiers (public, private, protected). But this pattern also
  rejects C++ constructs, which look like this:

    MyClass::MyClass()
    MyClass::~MyClass()
    MyClass::Item MyClass::Find(...

- The second part matches an identifier followed by a list of qualified
  names (i.e. identifiers separated by the C++ scope operator '::')
  separated by space or '*' followed by an opening parenthesis (with
  space between the tokens). It matches function declarations like

    struct item* get_head(...
    int Outer::Inner::Func(...

  Since the pattern requires at least two identifiers, GNU-style
  function definitions are ignored:

    void
    func(...

  Moreover, since the pattern does not allow punctuation other than '*',
  the following C++ constructs are not recognized:

  . template definitions:
      template<class T> int func(T arg)

  . functions returning references:
      const string& get_message()

  . functions returning templated types:
      vector<int> foo()

  . operator definitions:
      Value operator+(Value l, Value r)

- The third part of the pattern finally matches compound definitions.
  But it forgets about unions and namespaces, and also skips single-line
  definitions

    struct random_iterator_tag {};

  because no semicolon can occur on the line.

Change the first pattern to require a colon at the end of the line
(except for trailing space and comments), so that it does not reject
constructor or destructor definitions.

Notice that all interesting anchor points begin with an identifier or
keyword. But since there is a large variety of syntactical constructs
after the first "word", the simplest is to require only this word and
accept everything else. Therefore, this boils down to a line that begins
with a letter or underscore (optionally preceded by the C++ scope
operator '::' to accept functions returning a type anchored at the
global namespace). Replace the second and third part by a single pattern
that picks such a line.

This has the following desirable consequence:

- All constructs mentioned above are recognized.

and the following likely desirable consequences:

- Definitions of global variables and typedefs are recognized:

    int num_entries = 0;
    extern const char* help_text;
    typedef basic_string<wchar_t> wstring;

- Commonly used marco-ized boilerplate code is recognized:

    BEGIN_MESSAGE_MAP(CCanvas,CWnd)
    Q_DECLARE_METATYPE(MyStruct)
    PATTERNS("tex",...)

  (The last one is from this very patch.)

but also the following possibly undesirable consequence:

- When a label is not on a line by itself (except for a comment) it is
  no longer rejected, but can appear as a hunk header if it occurs at
  the beginning of a line:

    next:;

IMO, the benefits of the change outweigh the (possible) regressions by a
large margin.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 15:03:32 -07:00
Johannes Sixt
abf8f98602 userdiff: support unsigned and long long suffixes of integer constants
Do not split constants such as 123U, 456ll, 789UL at the first U or
second L.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 14:48:07 -07:00
Johannes Sixt
407e07f2a6 userdiff: support C++ ->* and .* operators in the word regexp
The character sequences ->* and .* are valid C++ operators. Keep them
together in --word-diff mode.

Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-03-21 14:47:50 -07:00
Adrian Johnson
39a87a29ce userdiff: update Ada patterns
- Allow extra space in "is new" and "is separate"
- Fix bug in word regex for numbers

Signed-off-by: Adrian Johnson <ajohnson@redneon.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-02-05 10:45:51 -08:00
Jeff King
0a5987fe5e userdiff: drop parse_driver function
When we parse userdiff config, we generally assume that

  diff.name.key

will affect the "key" value of the "name" driver. However,
without confirming that the key is a valid userdiff key, we
may accidentally conflict with the ancient "diff.color.*"
namespace. The current code is careful not to even create a
driver struct if we do not see a key that is known by the
diff-driver code.

However, this carefulness is unnecessary; the default driver
with no keys set behaves exactly the same as having no
driver at all. We can simply set up the driver struct as
soon as we see we have a config key that looks like a
driver. This makes the code a bit more readable.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-01-23 08:41:51 -08:00
Jeff King
d731f0ade1 convert some config callbacks to parse_config_key
These callers can drop some inline pointer arithmetic and
magic offset constants, making them more readable and less
error-prone (those constants had to match the lengths of
strings, but there is no automatic verification of that
fact).

The "ep" pointer (presumably for "end pointer"), which
points to the final key segment of the config variable, is
given the more standard name "key" to describe its function
rather than its derivation.

Signed-off-by: Jeff King <peff@peff.net>
Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-01-23 08:41:50 -08:00
Adrian Johnson
e90d065e64 Add userdiff patterns for Ada
Add Ada xfuncname and wordRegex patterns to the list of builtin
patterns.

Signed-off-by: Adrian Johnson <ajohnson@redneon.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-09-16 21:54:47 -07:00
Jeff King
6680a0874f drop odd return value semantics from userdiff_config
When the userdiff_config function was introduced in be58e70
(diff: unify external diff and funcname parsing code,
2008-10-05), it used a return value convention unlike any
other config callback. Like other callbacks, it used "-1" to
signal error. But it returned "1" to indicate that it found
something, and "0" otherwise; other callbacks simply
returned "0" to indicate that no error occurred.

This distinction was necessary at the time, because the
userdiff namespace overlapped slightly with the color
configuration namespace. So "diff.color.foo" could mean "the
'foo' slot of diff coloring" or "the 'foo' component of the
"color" userdiff driver". Because the color-parsing code
would die on an unknown color slot, we needed the userdiff
code to indicate that it had matched the variable, letting
us bypass the color-parsing code entirely.

Later, in 8b8e862 (ignore unknown color configuration,
2009-12-12), the color-parsing code learned to silently
ignore unknown slots. This means we no longer need to
protect userdiff-matched variables from reaching the
color-parsing code.

We can therefore change the userdiff_config calling
convention to a more normal one. This drops some code from
each caller, which is nice. But more importantly, it reduces
the cognitive load for readers who may wonder why
userdiff_config is unlike every other config callback.

There's no need to add a new test confirming that this
works; t4020 already contains a test that sets
diff.color.external.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-02-07 10:44:54 -08:00
Junio C Hamano
357ba5cf0d Merge branch 'tr/userdiff-c-returns-pointer'
* tr/userdiff-c-returns-pointer:
  userdiff: allow * between cpp funcname words
2011-12-13 22:57:19 -08:00
Thomas Rast
37e7793d47 userdiff: allow * between cpp funcname words
The cpp pattern, used for C and C++, would not match the start of a
declaration such as

  static char *prepare_index(int argc,

because it did not allow for * anywhere between the various words that
constitute the modifiers, type and function name.  Fix it.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-12-06 13:16:37 -08:00
Gustaf Hendeby
53b10a1405 Add built-in diff patterns for MATLAB code
MATLAB is often used in industry and academia for scientific
computations motivating it being included as a built-in pattern.

Signed-off-by: Gustaf Hendeby <hendeby@isy.liu.se>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-11-15 16:11:52 -08:00
Michael Haggerty
d932f4eb9f Rename git_checkattr() to git_check_attr()
Suggested by: Junio Hamano <gitster@pobox.com>

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-08-04 15:53:21 -07:00
Junio C Hamano
dbae1a1336 Merge branch 'jk/combine-diff-binary-etc'
* jk/combine-diff-binary-etc:
  combine-diff: respect textconv attributes
  refactor get_textconv to not require diff_filespec
  combine-diff: handle binary files as binary
  combine-diff: calculate mode_differs earlier
  combine-diff: split header printing into its own function
2011-06-29 17:03:10 -07:00
Jeff King
3813e69031 refactor get_textconv to not require diff_filespec
This function actually does two things:

  1. Load the userdiff driver for the filespec.

  2. Decide whether the driver has a textconv component, and
     initialize the textconv cache if applicable.

Only part (1) requires the filespec object, and some callers
may not have a filespec at all. So let's split them it into
two functions, and put part (2) with the userdiff code,
which is a better fit.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-23 15:46:02 -07:00
Jonathan Nieder
f143d9c695 userdiff/perl: tighten BEGIN/END block pattern to reject here-doc delimiters
A naive method of treating BEGIN/END blocks with a brace on the second
line as diff/grep funcname context involves also matching unrelated
lines that consist of all-caps letters:

	sub foo {
		print <<'EOF'
	text goes here
	...
	EOF
		... rest of foo ...
	}

That's not so great, because it means that "git diff" and "git grep
--show-function" would write "=EOF" or "@@ EOF" as context instead of
a more useful reminder like "@@ sub foo {".

To avoid this, tighten the pattern to only match the special block
names that perl accepts (namely BEGIN, END, INIT, CHECK, UNITCHECK,
AUTOLOAD, and DESTROY).  The list is taken from perl's toke.c.

Suggested-by: Jakub Narebski <jnareb@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-23 11:39:13 -07:00
Jonathan Nieder
ea2ca4497b userdiff/perl: catch sub with brace on second line
Accept

	sub foo
	{
	}

as an alternative to a more common style that introduces perl
functions with a brace on the first line (and likewise for BEGIN/END
blocks).  The new regex is a little hairy to avoid matching

	# forward declaration
	sub foo;

while continuing to match "sub foo($;@) {" and

	sub foo { # This routine is interesting;
		# in fact, the lines below explain how...

While at it, pay attention to Perl 5.14's "package foo {" syntax as an
alternative to the traditional "package foo;".

Requested-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-21 22:29:32 -07:00
Jonathan Nieder
12f0967a8a userdiff/perl: match full line of POD headers
The builtin perl userdiff driver is not greedy enough about catching
POD header lines.  Capture the whole line, so instead of just
declaring that we are in some "@@ =head1" section, diff/grep output
can explain that the enclosing section is about "@@ =head1 OPTIONS".

Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-21 22:29:32 -07:00
Jonathan Nieder
f12c66b9bb userdiff/perl: anchor "sub" and "package" patterns on the left
The userdiff funcname mechanism has no concept of nested scopes ---
instead, "git diff" and "git grep --show-function" simply label the
diff header with the most recent matching line.  Unfortunately that
means text following a subroutine in a POD section:

	=head1 DESCRIPTION

	You might use this facility like so:

		sub example {
			foo;
		}

	Now, having said that, let's say more about the facility.
	Blah blah blah ... etc etc.

gets the subroutine name instead of the POD header in its diff/grep
funcname header, making it harder to get oriented when reading a
diff without enough context.

The fix is simple: anchor the funcname syntax to the left margin so
nested subroutines and packages like this won't get picked up.  (The
builtin C++ funcname pattern already does the same thing.)  This means
the userdiff driver will misparse the idiom

	{
		my $static;
		sub foo {
			... use $static ...
		}
	}

but I think that's worth it; we can revisit this later if the userdiff
mechanism learns to keep track of the beginning and end of nested
scopes.

Reported-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-21 22:29:31 -07:00
Junio C Hamano
1bb4abeff7 Merge branch 'tr/diff-words-test'
* tr/diff-words-test:
  t4034 (diff --word-diff): add a minimum Perl drier test vector
  t4034 (diff --word-diff): style suggestions
  userdiff: simplify word-diff safeguard
  t4034: bulk verify builtin word regex sanity
2011-02-09 16:41:17 -08:00
Junio C Hamano
342953a686 Merge branch 'as/userdiff-pascal'
* as/userdiff-pascal:
  userdiff: match Pascal class methods
2011-01-24 10:54:12 -08:00
Jonathan Nieder
664d44ee7f userdiff: simplify word-diff safeguard
git's diff-words support has a detail that can be a little dangerous:
any text not matched by a given language's tokenization pattern is
treated as whitespace and changes in such text would go unnoticed.
Therefore each of the built-in regexes allows a special token type
consisting of a single non-whitespace character [^[:space:]].

To make sure UTF-8 sequences remain human readable, the builtin
regexes also have a special token type for runs of bytes with the high
bit set.  In English, non-ASCII characters are usually isolated so
this is analogous to the [^[:space:]] pattern, except it matches a
single _multibyte_ character despite use of the C locale.

Unfortunately it is easy to make typos or forget entirely to include
these catch-all token types when adding support for new languages (see
v1.7.3.5~16, userdiff: fix typo in ruby and python word regexes,
2010-12-18).  Avoid this by including them automatically within the
PATTERNS and IPATTERN macros.

While at it, change the UTF-8 sequence token type to match exactly one
non-ASCII multi-byte character, rather than an arbitrary run of them.

Suggested-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-18 08:59:39 -08:00
Alexey Shumkin
ad5b6942d5 userdiff: match Pascal class methods
Class declarations were already covered by the second pattern, but class
methods have the 'class' keyword in front too. Account for it.

Signed-off-by: Alexey Shumkin <zapped@mail.ru>
Acked-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-11 11:03:48 -08:00
Junio C Hamano
a25e47377d userdiff/perl: catch BEGIN/END/... and POD as headers
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-27 09:19:38 -08:00
Jonathan Nieder
71a5d4bc0e diff: funcname and word patterns for perl
The default function name discovery already works quite well for Perl
code... with the exception of here-documents (or rather their ending).

 sub foo {
	print <<END
 here-document
 END
	return 1;
 }

The default funcname pattern treats the unindented END line as a
function declaration and puts it in the @@ line of diff and "grep
--show-function" output.

With a little knowledge of perl syntax, we can do better.  You can
try it out by adding "*.perl diff=perl" to the gitattributes file.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-27 08:47:21 -08:00
Thomas Rast
b34f69f991 userdiff: fix typo in ruby and python word regexes
Both had an unclosed ] that ruined the safeguard against not matching
a non-space char.

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-12-18 22:58:40 -08:00
Brandon Casey
909a5494f8 userdiff.c: add builtin fortran regex patterns
This adds fortran xfuncname and wordRegex patterns to the list of builtin
patterns.  The intention is for the patterns to be appropriate for all
versions of fortran including 77, 90, 95.  The patterns can be enabled by
adding the diff=fortran attribute to the .gitattributes file for the
desired file glob.

This also adds a new macro named IPATTERN which is just like the PATTERNS
macro except it sets the REG_ICASE flag so that case will be ignored.

The test code in t4018 and the docs were updated as appropriate.

Signed-off-by: Brandon Casey <casey@nrlssc.navy.mil>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-09-10 09:38:29 -07:00
Petr Onderka
b221207db9 Userdiff patterns for C#
Add userdiff patterns for C#. This code is an improved version of
code by Adam Petaccia from 21 June 2009 mail to the list.

Signed-off-by: Petr Onderka <gsvick@gmail.com>
Acked-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-08-16 18:28:27 -07:00
Junio C Hamano
9559910cac Merge branch 'bs/userdiff-php'
* bs/userdiff-php:
  diff: Support visibility modifiers in the PHP hunk header regexp
2010-06-13 11:22:05 -07:00
Björn Steinbrink
6d2f208c3d diff: Support visibility modifiers in the PHP hunk header regexp
Starting with PHP5, class methods can have a visibility modifier, which
caused the methods not to be matched by the existing regexp, so extend
the regexp to match those modifiers. And while we're at it, allow the
"static" modifier as well.

Since the "static" modifier can appear either before or after the
visibility modifier, let's just allow any number of modifiers to appear
in any order, as that simplifies the regexp and shouldn't cause any
false positives.

Signed-off-by: Björn Steinbrink <B.Steinbrink@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-05-27 07:12:07 -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
Junio C Hamano
7fb0eaa289 git_attr(): fix function signature
The function took (name, namelen) as its arguments, but all the public
callers wanted to pass a full string.

Demote the counted-string interface to an internal API status, and allow
public callers to just pass the string to the function.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-01-16 20:39:59 -08:00
Paolo Bonzini
959e2e64a5 avoid exponential regex match for java and objc function names
In the old regex

^[ \t]*(([ \t]*[A-Za-z_][A-Za-z_0-9]*){2,}[ \t]*\([^;]*)$
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

you can backtrack arbitrarily from [A-Za-z_0-9]* into [A-Za-z_], thus
causing an exponential number of backtracks.  Ironically it also causes
the regex not to work as intended; for example "catch" can match the
underlined part of the regex, the first repetition matching "c" and
the second matching "atch".

The replacement regex avoids this problem, because it makes sure that
at least a space/tab is eaten on each repetition.  In other words,
a suffix of a repetition can never be a prefix of the next repetition.

Signed-off-by: Paolo Bonzini <bonzini@gnu.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-06-18 09:52:10 -07:00
Boyd Stephen Smith Jr
ae3b970ac3 Change the spelling of "wordregex".
Use "wordRegex" for configuration variable names.  Use "word_regex" for C
language tokens.

Signed-off-by: Boyd Stephen Smith Jr. <bss@iguanasuicide.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-21 23:52:16 -08:00
Thomas Rast
80c49c3de2 color-words: make regex configurable via attributes
Make the --color-words splitting regular expression configurable via
the diff driver's 'wordregex' attribute.  The user can then set the
driver on a file in .gitattributes.  If a regex is given on the
command line, it overrides the driver's setting.

We also provide built-in regexes for the languages that already had
funcname patterns, and add an appropriate diff driver entry for C/++.
(The patterns are designed to run UTF-8 sequences into a single chunk
to make sure they remain readable.)

Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-17 10:44:21 -08:00
Jeff King
c7534ef4a1 userdiff: require explicitly allowing textconv
Diffs that have been produced with textconv almost certainly
cannot be applied, so we want to be careful not to generate
them in things like format-patch.

This introduces a new diff options, ALLOW_TEXTCONV, which
controls this behavior. It is off by default, but is
explicitly turned on for the "log" family of commands, as
well as the "diff" porcelain (but not diff-* plumbing).

Because both text conversion and external diffing are
controlled by these diff options, we can get rid of the
"plumbing versus porcelain" distinction when reading the
config. This was an attempt to control the same thing, but
suffered from being too coarse-grained.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2008-10-26 14:09:48 -07:00
Jeff King
9cb92c390c diff: add filter for converting binary to text
When diffing binary files, it is sometimes nice to see the
differences of a canonical text form rather than either a
binary patch or simply "binary files differ."

Until now, the only option for doing this was to define an
external diff command to perform the diff. This was a lot of
work, since the external command needed to take care of
doing the diff itself (including mode changes), and lost the
benefit of git's colorization and other options.

This patch adds a text conversion option, which converts a
file to its canonical format before performing the diff.
This is less flexible than an arbitrary external diff, but
is much less work to set up. For example:

  $ echo '*.jpg diff=exif' >>.gitattributes
  $ git config diff.exif.textconv exiftool
  $ git config diff.exif.binary false

allows one to see jpg diffs represented by the text output
of exiftool.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-10-18 08:02:55 -07:00
Jeff King
122aa6f9c0 diff: introduce diff.<driver>.binary
The "diff" gitattribute is somewhat overloaded right now. It
can say one of three things:

  1. this file is definitely binary, or definitely not
     (i.e., diff or !diff)
  2. this file should use an external diff engine (i.e.,
     diff=foo, diff.foo.command = custom-script)
  3. this file should use particular funcname patterns
     (i.e., diff=foo, diff.foo.(x?)funcname = some-regex)

Most of the time, there is no conflict between these uses,
since using one implies that the other is irrelevant (e.g.,
an external diff engine will decide for itself whether the
file is binary).

However, there is at least one conflicting situation: there
is no way to say "use the regular rules to determine whether
this file is binary, but if we do diff it textually, use
this funcname pattern." That is, currently setting diff=foo
indicates that the file is definitely text.

This patch introduces a "binary" config option for a diff
driver, so that one can explicitly set diff.foo.binary. We
default this value to "don't know". That is, setting a diff
attribute to "foo" and using "diff.foo.funcname" will have
no effect on the binaryness of a file. To get the current
behavior, one can set diff.foo.binary to true.

This patch also has one additional advantage: it cleans up
the interface to the userdiff code a bit. Before, calling
code had to know more about whether attributes were false,
true, or unset to determine binaryness. Now that binaryness
is a property of a driver, we can represent these situations
just by passing back a driver struct.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-10-18 08:02:26 -07:00
Jeff King
be58e70dba diff: unify external diff and funcname parsing code
Both sets of code assume that one specifies a diff profile
as a gitattribute via the "diff=foo" attribute. They then
pull information about that profile from the config as
diff.foo.*.

The code for each is currently completely separate from the
other, which has several disadvantages:

  - there is duplication as we maintain code to create and
    search the separate lists of external drivers and
    funcname patterns

  - it is difficult to add new profile options, since it is
    unclear where they should go

  - the code is difficult to follow, as we rely on the
    "check if this file is binary" code to find the funcname
    pattern as a side effect. This is the first step in
    refactoring the binary-checking code.

This patch factors out these diff profiles into "userdiff"
drivers. A file with "diff=foo" uses the "foo" driver, which
is specified by a single struct.

Note that one major difference between the two pieces of
code is that the funcname patterns are always loaded,
whereas external drivers are loaded only for the "git diff"
porcelain; the new code takes care to retain that situation.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
2008-10-18 08:02:21 -07:00