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37 commits

Author SHA1 Message Date
René Scharfe
be39144954 userdiff: support regexec(3) with multi-byte support
Since 1819ad327b (grep: fix multibyte regex handling under macOS,
2022-08-26) we use the system library for all regular expression
matching on macOS, not just for git grep.  It supports multi-byte
strings and rejects invalid multi-byte characters.

This broke all built-in userdiff word regexes in UTF-8 locales because
they all include such invalid bytes in expressions that are intended to
match multi-byte characters without explicit support for that from the
regex engine.

"|[^[:space:]]|[\xc0-\xff][\x80-\xbf]+" is added to all built-in word
regexes to match a single non-space or multi-byte character.  The \xNN
characters are invalid if interpreted as UTF-8 because they have their
high bit set, which indicates they are part of a multi-byte character,
but they are surrounded by single-byte characters.

Replace that expression with "|[^[:space:]]" if the regex engine
supports multi-byte matching, as there is no need to have an explicit
range for multi-byte characters then.  Check for that capability at
runtime, because it depends on the locale and thus on environment
variables.  Construct the full replacement expression at build time
and just switch it in if necessary to avoid string manipulation and
allocations at runtime.

Additionally the word regex for tex contains the expression
"[a-zA-Z0-9\x80-\xff]+" with a similarly invalid range.  The best
replacement with only valid characters that I can come up with is
"([a-zA-Z0-9]|[^\x01-\x7f])+".  Unlike the original it matches NUL
characters, though.  Assuming that tex files usually don't contain NUL
this should be acceptable.

Reported-by: D. Ben Knoble <ben.knoble@gmail.com>
Reported-by: Eric Sunshine <sunshine@sunshineco.com>
Helped-by: Junio C Hamano <gitster@pobox.com>
Signed-off-by: René Scharfe <l.s.r@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2023-04-07 07:38:09 -07:00
Jaydeep P Das
09188ed930 userdiff: add builtin diff driver for kotlin language.
The xfuncname pattern finds func/class declarations
in diffs to display as a hunk header. The word_regex
pattern finds individual tokens in Kotlin code to generate
appropriate diffs.

This patch adds xfuncname regex and word_regex for Kotlin
language.

Signed-off-by: Jaydeep P Das <jaydeepjd.8914@gmail.com>
Acked-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-12 18:15:47 -08:00
Ævar Arnfjörð Bjarmason
16d4bd4f14 leak tests: mark some diff tests as passing with SANITIZE=leak
Mark some tests that match "*diff*" as passing when git is compiled
with SANITIZE=leak. They'll now be listed as running under the
"GIT_TEST_PASSING_SANITIZE_LEAK=true" test mode (the "linux-leaks" CI
target).

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-11-01 11:23:08 -07:00
Junio C Hamano
65c18913de Merge branch 'pw/word-diff-zero-width-matches'
The word-diff mode has been taught to work better with a word
regexp that can match an empty string.

* pw/word-diff-zero-width-matches:
  word diff: handle zero length matches
2021-05-14 08:26:06 +09:00
Phillip Wood
0324e8fc6b word diff: handle zero length matches
If find_word_boundaries() encounters a zero length match (which can be
caused by matching a newline or using '*' instead of '+' in the regex)
we stop splitting the input into words which generates an inaccurate
diff. To fix this increment the start point when there is a zero
length match and try a new match. This is safe as posix regular
expressions always return the longest available match so a zero length
match means there are no longer matches available from the current
position.

Commit bf82940dbf (color-words: enable REG_NEWLINE to help user,
2009-01-17) prevented matching newlines in negated character classes
but it is still possible for the user to have an explicit newline
match in the regex which could cause a zero length match.

One could argue that having explicit newline matches or using '*'
rather than '+' are user errors but it seems to be better to work
round them than produce inaccurate diffs.

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-05-05 18:53:42 +09:00
Atharva Raykar
a437390310 userdiff: add support for Scheme
Add a diff driver for Scheme-like languages which recognizes top level
and local `define` forms, whether it is a function definition, binding,
syntax definition or a user-defined `define-xyzzy` form.

Also supports R6RS `library` forms, `module` forms along with class and
struct declarations used in Racket (PLT Scheme).

Alternate "def" syntax such as those in Gerbil Scheme are also
supported, like defstruct, defsyntax and so on.

The rationale for picking `define` forms for the hunk headers is because
it is usually the only significant form for defining the structure of
the program, and it is a common pattern for schemers to have local
function definitions to hide their visibility, so it is not only the top
level `define`'s that are of interest. Schemers also extend the language
with macros to provide their own define forms (for example, something
like a `define-test-suite`) which is also captured in the hunk header.

Since it is common practice to extend syntax with variants of a form
like `module+`, `class*` etc, those have been supported as well.

The word regex is a best-effort attempt to conform to R7RS[1] valid
identifiers, symbols and numbers.

[1] https://small.r7rs.org/attachment/r7rs.pdf (section 2.1)

Signed-off-by: Atharva Raykar <raykar.ath@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-04-08 13:56:09 -07:00
Ævar Arnfjörð Bjarmason
ebd73f50c6 test libs: rename "diff-lib" to "lib-diff"
Rename the "diff-lib" to "lib-diff". With this rename and preceding
commits there is no remaining t/*lib* which doesn't follow the
convention of being called t/lib-*.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-02-12 11:58:21 -08:00
Martin Ågren
c76b84a121 t: don't spuriously close and reopen quotes
In the test scripts, the recommended style is, e.g.:

    test_expect_success 'name' '
        do-something somehow &&
        do-some-more testing
    '

When using this style, any single quote in the multi-line test section
is actually closing the lone single quotes that surround it.

It can be a non-issue in practice:

    test_expect_success 'sed a little' '
        sed -e 's/hi/lo/' in >out # "ok": no whitespace in s/hi/lo/
    '

Or it can be a bug in the test, e.g., because variable interpolation
happens before the test even begins executing:

    v=abc

    test_expect_success 'variable interpolation' '
        v=def &&
        echo '"$v"' # abc
    '

Change several such in-test single quotes to use double quotes instead
or, in a few cases, drop them altogether. These were identified using
some crude grepping. We're not fixing any test bugs here, but we're
hopefully making these tests slightly easier to grok and to maintain.

There are legitimate use cases for closing a quote and opening a new
one, e.g., both '\'' and '"'"' can be used to produce a literal single
quote. I'm not touching any of those here.

In t9401, tuck the redirecting ">" to the filename while we're touching
those lines.

Signed-off-by: Martin Ågren <martin.agren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2020-08-06 15:14:32 -07:00
brian m. carlson
0253e126a2 t4034: abstract away SHA-1-specific constants
Adjust the test so that it computes variables for object IDs instead of
using hard-coded hashes.  Move some expected result heredocs around so
that they can use computed variables.

Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-10-28 11:34:58 +09:00
Stephen Boyd
3c81760bc6 userdiff: add a builtin pattern for dts files
The Linux kernel receives many patches to the devicetree files each
release. The hunk header for those patches typically show nothing,
making it difficult to figure out what node is being modified without
applying the patch or opening the file and seeking to the context. Let's
add a builtin 'dts' pattern to git so that users can get better diff
output on dts files when they use the diff=dts driver.

The regex has been constructed based on the spec at devicetree.org[1]
and with some help from Johannes Sixt.

[1] https://github.com/devicetree-org/devicetree-specification/releases/latest

Cc: Rob Herring <robh+dt@kernel.org>
Cc: Frank Rowand <frowand.list@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-08-21 15:09:34 -07:00
William Duclot
0719f3eecd userdiff: add built-in pattern for CSS
CSS is widely used, motivating it being included as a built-in pattern.

It must be noted that the word_regex for CSS (i.e. the regex defining
what is a word in the language) does not consider '.' and '#' characters
(in CSS selectors) to be part of the word. This behavior is documented
by the test t/t4018/css-rule.
The logic behind this behavior is the following: identifiers in CSS
selectors are identifiers in a HTML/XML document. Therefore, the '.'/'#'
character are not part of the identifier, but an indicator of the nature
of the identifier in HTML/XML (class or id). Diffing ".class1" and
".class2" must show that the class name is changed, but we still are
selecting a class.

Logic behind the "pattern" regex is:
    1. reject lines ending with a colon/semicolon (properties)
    2. if a line begins with a name in column 1, pick the whole line

Credits to Johannes Sixt (j6t@kdbg.org) for the pattern regex and most
of the tests.

Signed-off-by: William Duclot <william.duclot@ensimag.grenoble-inp.fr>
Signed-off-by: Matthieu Moy <matthieu.moy@grenoble-inp.fr>
Reviewed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2016-06-03 14:45:56 -07:00
Yann Droneaud
ff73aa405f t4034: use test_config/test_unconfig to set/unset git config variables
Instead of using construct such as:
    test_when_finished "git config --unset <key>"
    git config <key> <value>
uses
    test_config <key> <value>
The latter takes care of removing <key> at the end of the test.

Additionally, instead of
     git config <key> ""
or
     git config --unset <key>
uses
     test_unconfig <key>
The latter doesn't failed if <key> is not defined.

Signed-off-by: Yann Droneaud <ydroneaud@opteya.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2013-03-25 08:50:53 -07:00
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
Thomas Rast
6440d3417c diff: tweak a _copy_ of diff_options with word-diff
When using word diff, the code sets the word_regex from various
defaults if it was not set already.  The problem is that it does this
on the original diff_options, which will also be used in subsequent
diffs.

This means that when the word_regex is not given on the command line,
only the first diff for which a setting for word_regex (either from
attributes or diff.wordRegex) ever takes effect.  This value then
propagates to the rest of the diff runs and in particular prevents
further attribute lookups.

Fix the problem of changing diff state once and for all, by working
with a _copy_ of the diff_options.

Noticed-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-03-14 14:41:20 -07:00
Johannes Sixt
62d39359af t4034: diff.*.wordregex should not be "sticky" in --word-diff
The test case applies a custom wordRegex to one file in a diff, and expects
that the default word splitting applies to the second file in the diff.
But the custom wordRegex is also incorrectly used for the second file.

Helped-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Johannes Sixt <j6t@kdbg.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-03-14 14:39:01 -07:00
Junio C Hamano
05c65cb116 Merge branch 'tr/maint-word-diff-incomplete-line'
* tr/maint-word-diff-incomplete-line:
  word-diff: ignore '\ No newline at eof' marker
2012-01-18 15:16:19 -08:00
Thomas Rast
c7c2bc0ac9 word-diff: ignore '\ No newline at eof' marker
The word-diff logic accumulates + and - lines until another line type
appears (normally [ @\]), at which point it generates the word diff.
This is usually correct, but it breaks when the preimage does not have
a newline at EOF:

  $ printf "%s" "a a a" >a
  $ printf "%s\n" "a ab a" >b
  $ git diff --no-index --word-diff a b
  diff --git 1/a 2/b
  index 9f68e94..6a7c02f 100644
  --- 1/a
  +++ 2/b
  @@ -1 +1 @@
  [-a a a-]
   No newline at end of file
  {+a ab a+}

Because of the order of the lines in a unified diff

  @@ -1 +1 @@
  -a a a
  \ No newline at end of file
  +a ab a

the '\' line flushed the buffers, and the - and + lines were never
matched with each other.

A proper fix would defer such markers until the end of the hunk.
However, word-diff is inherently whitespace-ignoring, so as a cheap
fix simply ignore the marker (and hide it from the output).

We use a prefix match for '\ ' to parallel the logic in
apply.c:parse_fragment().  We currently do not localize this string
(just accept other variants of it in git-apply), but this should be
future-proof.

Noticed-by: Ivan Shirokoff <shirokoff@yandex-team.ru>
Signed-off-by: Thomas Rast <trast@student.ethz.ch>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2012-01-12 11:27:41 -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
Jim Meyering
42536dd9b9 do not read beyond end of malloc'd buffer
With diff.suppress-blank-empty=true, "git diff --word-diff" would
output data that had been read from uninitialized heap memory.
The problem was that fn_out_consume did not account for the
possibility of a line with length 1, i.e., the empty context line
that diff.suppress-blank-empty=true converts from " \n" to "\n".
Since it assumed there would always be a prefix character (the space),
it decremented "len" unconditionally, thus passing len=0 to emit_line,
which would then blindly call emit_line_0 with len=-1 which would
pass that value on to fwrite as SIZE_MAX.  Boom.

Signed-off-by: Jim Meyering <meyering@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-05-20 11:39:49 -07:00
Junio C Hamano
5269edf170 t4034 (diff --word-diff): add a minimum Perl drier test vector
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-18 09:44:22 -08:00
Jonathan Nieder
5094d15874 t4034 (diff --word-diff): style suggestions
Rearrange code to be easier to browse:

 - first data
 - then functions
 - then test assertions

Mark up inline test vectors as

  cat >vector <<-\EOF
	data
	data
  EOF

for visual scannability.  Use words like "set up" for tests that set
up for other tests, to make it obvious which tests are safe to skip.
Use repeated function calls instead of a loop for the
language-specific tests, so the invocations can be easily tweaked
individually (for example if one starts to fail).

This means if you add a new subdirectory to t4034/, it will not be
automatically used.  I think that's worth it for the added
explicitness.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2011-01-18 09:02:23 -08:00
Thomas Rast
8d96e7288f t4034: bulk verify builtin word regex sanity
The builtin word regexes should be tested with some simple examples
against simple issues.  Do this in bulk.

Mainly due to a lack of language knowledge and inspiration, most of
the test cases (cpp, csharp, java, objc, pascal, php, python, ruby)
are directly based off a C operator precedence table to verify that
all operators are split correctly.  This means that they are probably
incomplete or inaccurate except for 'cpp' itself.

Still, they are good enough to already have uncovered a typo in the
python and ruby patterns.

'fortran' is based on my anecdotal knowledge of the DO10I parsing
rules, and thus probably useless.  The rest (bibtex, html, tex) are an
ad-hoc test of what I consider important splits in those languages.

Signed-off-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 08:51:58 -08:00
Junio C Hamano
b3ff808b71 Merge branch 'en/and-cascade-tests'
* en/and-cascade-tests: (25 commits)
  t4124 (apply --whitespace): use test_might_fail
  t3404: do not use 'describe' to implement test_cmp_rev
  t3404 (rebase -i): introduce helper to check position of HEAD
  t3404 (rebase -i): move comment to description
  t3404 (rebase -i): unroll test_commit loops
  t3301 (notes): use test_expect_code for clarity
  t1400 (update-ref): use test_must_fail
  t1502 (rev-parse --parseopt): test exit code from "-h"
  t6022 (renaming merge): chain test commands with &&
  test-lib: introduce test_line_count to measure files
  tests: add missing &&, batch 2
  tests: add missing &&
  Introduce sane_unset and use it to ensure proper && chaining
  t7800 (difftool): add missing &&
  t7601 (merge-pull-config): add missing &&
  t7001 (mv): add missing &&
  t6016 (rev-list-graph-simplify-history): add missing &&
  t5602 (clone-remote-exec): add missing &&
  t4026 (color): remove unneeded and unchained command
  t4019 (diff-wserror): add lots of missing &&
  ...

Conflicts:
	t/t7006-pager.sh
2010-11-24 15:51:49 -08:00
Jonathan Nieder
a48fcd8369 tests: add missing &&
Breaks in a test assertion's && chain can potentially hide
failures from earlier commands in the chain.

Commands intended to fail should be marked with !, test_must_fail, or
test_might_fail.  The examples in this patch do not require that.

Signed-off-by: Jonathan Nieder <jrnieder@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-11-09 11:59:49 -08:00
Kevin Ballard
a471833d51 test-lib: extend test_decode_color to handle more color codes
Enhance the test_decode_color function to handle all common color codes,
including background colors and escapes that contain multiple codes.
This change necessitates changing <WHITE> to <BOLD>, so update t4034
as well.

This change is necessary for the next commit in order to test
background colors properly.

Signed-off-by: Kevin Ballard <kevin@sb.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2010-10-20 16:10:14 -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
c2ff10c98e Merge branch 'jk/1.7.0-status'
* jk/1.7.0-status:
  status/commit: do not suggest "reset HEAD <path>" while merging
  commit/status: "git add <path>" is not necessarily how to resolve
  commit/status: check $GIT_DIR/MERGE_HEAD only once
  t7508-status: test all modes with color
  t7508-status: status --porcelain ignores relative paths setting
  status: reduce duplicated setup code
  status: disable color for porcelain format
  status -s: obey color.status
  builtin-commit: refactor short-status code into wt-status.c
  t7508-status.sh: Add tests for status -s
  status -s: respect the status.relativePaths option
  docs: note that status configuration affects only long format
  commit: support alternate status formats
  status: add --porcelain output format
  status: refactor format option parsing
  status: refactor short-mode printing to its own function
  status: typo fix in usage
  git status: not "commit --dry-run" anymore
  git stat -s: short status output
  git stat: the beginning of "status that is not a dry-run of commit"

Conflicts:
	t/t4034-diff-words.sh
	wt-status.c
2009-12-27 23:01:32 -08:00
Michael J Gruber
68cfc6f551 t7508-status: test all modes with color
Move a useful script function to decode colored output to
text form from t4034 and use it in this test as well.

Signed-off-by: Michael J Gruber <git@drmicha.warpmail.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-12-08 21:52:47 -08:00
Bert Wesarg
89cb73a19a Give the hunk comment its own color
Inspired by the coloring of quilt.

Introduce a separate color and paint the hunk comment part, i.e. the name
of the function, in a separate color "diff.func" (defaults to plain).

Whitespace between hunk header and hunk comment is printed in plain color.

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-28 10:05:44 -08:00
Junio C Hamano
06a4755270 emit_line(): don't emit an empty <SET><RESET> followed by a newline
When emit_line() is called with an empty line (but non-zero length, as we
send line terminating LF or CRLF to the function), it used to emit
<SET><RESET> followed by a newline.  Stop the wastefulness.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-11-27 22:33:53 -08:00
Johannes Schindelin
a4ca1465ec diff --color-words -U0: fix the location of hunk headers
Colored word diff without context lines firstly printed all the hunk
headers among each other and then printed the diff.

This was due to the code relying on getting at least one context line at
the end of each hunk, where the colored words would be flushed (it is
done that way to be able to ignore rewrapped lines).

Noticed by Markus Heidelberg.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-10-30 09:42:56 -07:00
Markus Heidelberg
168eff3c80 t4034-diff-words: add a test for word diff without context
Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-10-30 09:42:52 -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
Boyd Stephen Smith Jr
98a4d87b87 color-words: Support diff.wordregex config option
When diff is invoked with --color-words (w/o =regex), use the regular
expression the user has configured as diff.wordregex.

diff drivers configured via attributes take precedence over the
diff.wordregex-words setting.  If the user wants to change them, they have
their own configuration variables.

Signed-off-by: Boyd Stephen Smith Jr <bss@iguanasuicide.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-21 00:51:12 -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
Johannes Schindelin
2b6a5417d7 color-words: take an optional regular expression describing words
In some applications, words are not delimited by white space.  To
allow for that, you can specify a regular expression describing
what makes a word with

	git diff --color-words='[A-Za-z0-9]+'

Note that words cannot contain newline characters.

As suggested by Thomas Rast, the words are the exact matches of the
regular expression.

Note that a regular expression beginning with a '^' will match only
a word at the beginning of the hunk, not a word at the beginning of
a line, and is probably not what you want.

This commit contains a quoting fix by Thomas Rast.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-17 10:43:08 -08:00
Johannes Schindelin
2e5d2003b2 color-words: change algorithm to allow for 0-character word boundaries
Up until now, the color-words code assumed that word boundaries are
identical to white space characters.

Therefore, it could get away with a very simple scheme: it copied the
hunks, substituted newlines for each white space character, called
libxdiff with the processed text, and then identified the text to
output by the offsets (which agreed since the original text had the
same length).

This code was ugly, for a number of reasons:

- it was impossible to introduce 0-character word boundaries,

- we had to print everything word by word, and

- the code needed extra special handling of newlines in the removed part.

Fix all of these issues by processing the text such that

- we build word lists, separated by newlines,

- we remember the original offsets for every word, and

- after calling libxdiff on the wordlists, we parse the hunk headers, and
  find the corresponding offsets, and then

- we print the removed/added parts in one go.

The pre and post samples in the test were provided by Santi Béjar.

Note that there is some strange special handling of hunk headers where
one line range is 0 due to POSIX: in this case, the start is one too
low.  In other words a hunk header '@@ -1,0 +2 @@' actually means that
the line must be added after the _second_ line of the pre text, _not_
the first.

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2009-01-17 10:42:41 -08:00