diff: add -I<regex> that ignores matching changes
Add a new diff option that enables ignoring changes whose all lines (changed, removed, and added) match a given regular expression. This is similar to the -I/--ignore-matching-lines option in standalone diff utilities and can be used e.g. to ignore changes which only affect code comments or to look for unrelated changes in commits containing a large number of automatically applied modifications (e.g. a tree-wide string replacement). The difference between -G/-S and the new -I option is that the latter filters output on a per-change basis. Use the 'ignore' field of xdchange_t for marking a change as ignored or not. Since the same field is used by --ignore-blank-lines, identical hunk emitting rules apply for --ignore-blank-lines and -I. These two options can also be used together in the same git invocation (they are complementary to each other). Rename xdl_mark_ignorable() to xdl_mark_ignorable_lines(), to indicate that it is logically a "sibling" of xdl_mark_ignorable_regex() rather than its "parent". Signed-off-by: Michał Kępień <michal@isc.org> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Michał Kępień committed
Oct 20, 2020 at 08:48 UTC
296d4a94e7231a1d57356889f51bff57a1a3c5a1
7 files changed
+221
-2
Documentation/diff-options.txt
+5
@@ -681,6 +681,11 @@ endif::git-format-patch[]
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--ignore-blank-lines::
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Ignore changes whose lines are all blank.
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+-I<regex>::
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+--ignore-matching-lines=<regex>::
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+ Ignore changes whose all lines match <regex>. This option may
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+ be specified more than once.
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+
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--inter-hunk-context=<lines>::
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Show the context between diff hunks, up to the specified number
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of lines, thereby fusing hunks that are close to each other.
diff.c
+23
@@ -3584,6 +3584,8 @@ static void builtin_diff(const char *name_a,
3584
if (header.len && !o->flags.suppress_diff_headers)
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ecbdata.header = &header;
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xpp.flags = o->xdl_opts;
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+ xpp.ignore_regex = o->ignore_regex;
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+ xpp.ignore_regex_nr = o->ignore_regex_nr;
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xpp.anchors = o->anchors;
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xpp.anchors_nr = o->anchors_nr;
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xecfg.ctxlen = o->context;
@@ -3711,6 +3713,8 @@ static void builtin_diffstat(const char *name_a, const char *name_b,
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memset(&xpp, 0, sizeof(xpp));
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memset(&xecfg, 0, sizeof(xecfg));
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xpp.flags = o->xdl_opts;
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+ xpp.ignore_regex = o->ignore_regex;
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+ xpp.ignore_regex_nr = o->ignore_regex_nr;
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xpp.anchors = o->anchors;
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xpp.anchors_nr = o->anchors_nr;
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xecfg.ctxlen = o->context;
@@ -5174,6 +5178,22 @@ static int diff_opt_patience(const struct option *opt,
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return 0;
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}
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+static int diff_opt_ignore_regex(const struct option *opt,
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+ const char *arg, int unset)
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+{
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+ struct diff_options *options = opt->value;
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+ regex_t *regex;
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+
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+ BUG_ON_OPT_NEG(unset);
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+ regex = xmalloc(sizeof(*regex));
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+ if (regcomp(regex, arg, REG_EXTENDED | REG_NEWLINE))
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+ return error(_("invalid regex given to -I: '%s'"), arg);
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+ ALLOC_GROW(options->ignore_regex, options->ignore_regex_nr + 1,
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+ options->ignore_regex_alloc);
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+ options->ignore_regex[options->ignore_regex_nr++] = regex;
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+ return 0;
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+}
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+
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static int diff_opt_pickaxe_regex(const struct option *opt,
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const char *arg, int unset)
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{
@@ -5462,6 +5482,9 @@ static void prep_parse_options(struct diff_options *options)
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OPT_BIT_F(0, "ignore-blank-lines", &options->xdl_opts,
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N_("ignore changes whose lines are all blank"),
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XDF_IGNORE_BLANK_LINES, PARSE_OPT_NONEG),
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+ OPT_CALLBACK_F('I', "ignore-matching-lines", options, N_("<regex>"),
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+ N_("ignore changes whose all lines match <regex>"),
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+ 0, diff_opt_ignore_regex),
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OPT_BIT(0, "indent-heuristic", &options->xdl_opts,
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N_("heuristic to shift diff hunk boundaries for easy reading"),
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XDF_INDENT_HEURISTIC),
diff.h
+4
@@ -234,6 +234,10 @@ struct diff_options {
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*/
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const char *pickaxe;
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+ /* -I<regex> */
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+ regex_t **ignore_regex;
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+ size_t ignore_regex_nr, ignore_regex_alloc;
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+
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const char *single_follow;
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const char *a_prefix, *b_prefix;
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const char *line_prefix;
t/t4013-diff-various.sh
+41
@@ -6,6 +6,7 @@
6
test_description='Various diff formatting options'
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8
. ./test-lib.sh
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+. "$TEST_DIRECTORY"/diff-lib.sh
10
11
test_expect_success setup '
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@@ -309,6 +310,7 @@ log -SF master --max-count=2
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log -GF master
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log -GF -p master
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log -GF -p --pickaxe-all master
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+log -IA -IB -I1 -I2 -p master
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log --decorate --all
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log --decorate=full --all
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@@ -449,4 +451,43 @@ test_expect_success 'diff-tree --stdin with log formatting' '
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test_cmp expect actual
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'
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+test_expect_success 'diff -I<regex>: setup' '
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+ git checkout master &&
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+ test_seq 50 >file0 &&
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+ git commit -m "Set up -I<regex> test file" file0 &&
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+ test_seq 50 | sed -e "s/13/ten and three/" -e "/7\$/d" >file0 &&
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+ echo >>file0
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+'
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+test_expect_success 'diff -I<regex>' '
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+ git diff --ignore-blank-lines -I"ten.*e" -I"^[124-9]" >actual &&
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+ cat >expect <<-\EOF &&
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+ diff --git a/file0 b/file0
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+ --- a/file0
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+ +++ b/file0
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+ @@ -34,7 +31,6 @@
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+ 34
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+ 35
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+ 36
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+ -37
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+ 38
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+ 39
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+ 40
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+ EOF
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+ compare_diff_patch expect actual
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+'
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+
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+test_expect_success 'diff -I<regex> --stat' '
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+ git diff --stat --ignore-blank-lines -I"ten.*e" -I"^[124-9]" >actual &&
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+ cat >expect <<-\EOF &&
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+ file0 | 1 -
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+ 1 file changed, 1 deletion(-)
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+ EOF
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+ test_cmp expect actual
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+'
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+
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+test_expect_success 'diff -I<regex>: detect malformed regex' '
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+ test_expect_code 129 git diff --ignore-matching-lines="^[124-9" 2>error &&
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+ test_i18ngrep "invalid regex given to -I: " error
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+'
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+
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test_done
t/t4013/diff.log_-IA_-IB_-I1_-I2_-p_master
new
+99
@@ -0,0 +1,99 @@
1
+$ git log -IA -IB -I1 -I2 -p master
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+commit 59d314ad6f356dd08601a4cd5e530381da3e3c64
3
+Merge: 9a6d494 c7a2ab9
4
+Author: A U Thor <author@example.com>
5
+Date: Mon Jun 26 00:04:00 2006 +0000
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+
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+ Merge branch 'side'
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+
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+commit c7a2ab9e8eac7b117442a607d5a9b3950ae34d5a
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+Author: A U Thor <author@example.com>
11
+Date: Mon Jun 26 00:03:00 2006 +0000
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+
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+ Side
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+
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+diff --git a/file0 b/file0
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+index 01e79c3..f4615da 100644
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+--- a/file0
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++++ b/file0
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+@@ -1,3 +1,6 @@
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+ 1
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+ 2
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+ 3
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++A
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++B
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++C
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+diff --git a/file3 b/file3
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+new file mode 100644
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+index 0000000..7289e35
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+
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+commit 9a6d4949b6b76956d9d5e26f2791ec2ceff5fdc0
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+Author: A U Thor <author@example.com>
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+Date: Mon Jun 26 00:02:00 2006 +0000
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+
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+ Third
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+
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+diff --git a/dir/sub b/dir/sub
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+index 8422d40..cead32e 100644
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+--- a/dir/sub
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++++ b/dir/sub
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+@@ -2,3 +2,5 @@ A
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+ B
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+ C
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+ D
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++E
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++F
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+diff --git a/file1 b/file1
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+new file mode 100644
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+index 0000000..b1e6722
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+--- /dev/null
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++++ b/file1
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+@@ -0,0 +1,3 @@
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++A
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++B
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++C
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+
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+commit 1bde4ae5f36c8d9abe3a0fce0c6aab3c4a12fe44
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+Author: A U Thor <author@example.com>
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+Date: Mon Jun 26 00:01:00 2006 +0000
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+
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+ Second
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+
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+ This is the second commit.
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+
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+diff --git a/dir/sub b/dir/sub
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+index 35d242b..8422d40 100644
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+--- a/dir/sub
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++++ b/dir/sub
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+@@ -1,2 +1,4 @@
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+ A
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+ B
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++C
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++D
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+diff --git a/file0 b/file0
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+index 01e79c3..b414108 100644
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+--- a/file0
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++++ b/file0
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+@@ -1,3 +1,6 @@
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+ 1
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+ 2
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+ 3
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++4
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++5
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++6
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+diff --git a/file2 b/file2
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+deleted file mode 100644
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+index 01e79c3..0000000
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+--- a/file2
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++++ /dev/null
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+@@ -1,3 +0,0 @@
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+-1
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+-2
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+-3
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+
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+commit 444ac553ac7612cc88969031b02b3767fb8a353a
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+Author: A U Thor <author@example.com>
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+Date: Mon Jun 26 00:00:00 2006 +0000
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+
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+ Initial
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+$
xdiff/xdiff.h
+4
@@ -79,6 +79,10 @@ typedef struct s_mmbuffer {
79
typedef struct s_xpparam {
80
unsigned long flags;
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82
+ /* -I<regex> */
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+ regex_t **ignore_regex;
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+ size_t ignore_regex_nr;
85
+
86
/* See Documentation/diff-options.txt. */
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char **anchors;
88
size_t anchors_nr;
xdiff/xdiffi.c
+45
-2
@@ -998,7 +998,7 @@ static int xdl_call_hunk_func(xdfenv_t *xe, xdchange_t *xscr, xdemitcb_t *ecb,
998
return 0;
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}
1000
1001
-static void xdl_mark_ignorable(xdchange_t *xscr, xdfenv_t *xe, long flags)
1001
+static void xdl_mark_ignorable_lines(xdchange_t *xscr, xdfenv_t *xe, long flags)
1002
{
1003
xdchange_t *xch;
1004
@@ -1019,6 +1019,46 @@ static void xdl_mark_ignorable(xdchange_t *xscr, xdfenv_t *xe, long flags)
1019
}
1020
}
1021
1022
+static int record_matches_regex(xrecord_t *rec, xpparam_t const *xpp) {
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+ regmatch_t regmatch;
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+ int i;
1025
+
1026
+ for (i = 0; i < xpp->ignore_regex_nr; i++)
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+ if (!regexec_buf(xpp->ignore_regex[i], rec->ptr, rec->size, 1,
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+ ®match, 0))
1029
+ return 1;
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+
1031
+ return 0;
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+}
1033
+
1034
+static void xdl_mark_ignorable_regex(xdchange_t *xscr, const xdfenv_t *xe,
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+ xpparam_t const *xpp)
1036
+{
1037
+ xdchange_t *xch;
1038
+
1039
+ for (xch = xscr; xch; xch = xch->next) {
1040
+ xrecord_t **rec;
1041
+ int ignore = 1;
1042
+ long i;
1043
+
1044
+ /*
1045
+ * Do not override --ignore-blank-lines.
1046
+ */
1047
+ if (xch->ignore)
1048
+ continue;
1049
+
1050
+ rec = &xe->xdf1.recs[xch->i1];
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+ for (i = 0; i < xch->chg1 && ignore; i++)
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+ ignore = record_matches_regex(rec[i], xpp);
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+
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+ rec = &xe->xdf2.recs[xch->i2];
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+ for (i = 0; i < xch->chg2 && ignore; i++)
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+ ignore = record_matches_regex(rec[i], xpp);
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+
1058
+ xch->ignore = ignore;
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+ }
1060
+}
1061
+
1062
int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
1063
xdemitconf_t const *xecfg, xdemitcb_t *ecb) {
1064
xdchange_t *xscr;
@@ -1038,7 +1078,10 @@ int xdl_diff(mmfile_t *mf1, mmfile_t *mf2, xpparam_t const *xpp,
1078
}
1079
if (xscr) {
1080
if (xpp->flags & XDF_IGNORE_BLANK_LINES)
1041
- xdl_mark_ignorable(xscr, &xe, xpp->flags);
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+ xdl_mark_ignorable_lines(xscr, &xe, xpp->flags);
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+
1083
+ if (xpp->ignore_regex)
1084
+ xdl_mark_ignorable_regex(xscr, &xe, xpp);
1085
1086
if (ef(&xe, xscr, ecb, xecfg) < 0) {
1087