diff-no-index: DWIM "diff D F" into "diff D/F F"

"git diff --no-index" was supposed to be a poor-man's approach to
allow using Git diff goodies outside of a Git repository, without
having to patch mainstream diff implementations.

Unlike a POSIX diff that treats "diff D F" (or "diff F D") as a
request to compare D/F and F (or F and D/F) when D is a directory
and F is a file, however, we did not accept such a command line and
instead barfed with "file/directory conflict".

Imitate what POSIX diff does and append the basename of the file
after the name of the directory before comparing.

Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Junio C Hamano 2015-03-25 16:11:39 -07:00
parent 282616c72d
commit c9e1f2c7f2
2 changed files with 65 additions and 0 deletions

View File

@ -182,12 +182,50 @@ static int queue_diff(struct diff_options *o,
}
}
/* append basename of F to D */
static void append_basename(struct strbuf *path, const char *dir, const char *file)
{
const char *tail = strrchr(file, '/');
strbuf_addstr(path, dir);
while (path->len && path->buf[path->len - 1] == '/')
path->len--;
strbuf_addch(path, '/');
strbuf_addstr(path, tail ? tail + 1 : file);
}
/*
* DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
* Note that we append the basename of F to D/, so "diff a/b/file D"
* becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
*/
static void fixup_paths(const char **path, struct strbuf *replacement)
{
unsigned int isdir0, isdir1;
if (path[0] == file_from_standard_input ||
path[1] == file_from_standard_input)
return;
isdir0 = is_directory(path[0]);
isdir1 = is_directory(path[1]);
if (isdir0 == isdir1)
return;
if (isdir0) {
append_basename(replacement, path[0], path[1]);
path[0] = replacement->buf;
} else {
append_basename(replacement, path[1], path[0]);
path[1] = replacement->buf;
}
}
void diff_no_index(struct rev_info *revs,
int argc, const char **argv,
const char *prefix)
{
int i, prefixlen;
const char *paths[2];
struct strbuf replacement = STRBUF_INIT;
diff_setup(&revs->diffopt);
for (i = 1; i < argc - 2; ) {
@ -217,6 +255,9 @@ void diff_no_index(struct rev_info *revs,
p = xstrdup(prefix_filename(prefix, prefixlen, p));
paths[i] = p;
}
fixup_paths(paths, &replacement);
revs->diffopt.skip_stat_unmatch = 1;
if (!revs->diffopt.output_format)
revs->diffopt.output_format = DIFF_FORMAT_PATCH;
@ -235,6 +276,8 @@ void diff_no_index(struct rev_info *revs,
diffcore_std(&revs->diffopt);
diff_flush(&revs->diffopt);
strbuf_release(&replacement);
/*
* The return code for --no-index imitates diff(1):
* 0 = no changes, 1 = changes, else error

View File

@ -55,4 +55,26 @@ test_expect_success 'git diff --no-index executed outside repo gives correct err
)
'
test_expect_success 'diff D F and diff F D' '
(
cd repo &&
echo in-repo >a &&
echo non-repo >../non/git/a &&
mkdir sub &&
echo sub-repo >sub/a &&
test_must_fail git diff --no-index sub/a ../non/git/a >expect &&
test_must_fail git diff --no-index sub/a ../non/git/ >actual &&
test_cmp expect actual &&
test_must_fail git diff --no-index a ../non/git/a >expect &&
test_must_fail git diff --no-index a ../non/git/ >actual &&
test_cmp expect actual &&
test_must_fail git diff --no-index ../non/git/a a >expect &&
test_must_fail git diff --no-index ../non/git a >actual &&
test_cmp expect actual
)
'
test_done