"add -p": work-around an old laziness that does not coalesce hunks

Since 0beee4c (git-add--interactive: remove hunk coalescing, 2008-07-02),
"git add--interactive" behaves lazily and passes overlapping hunks to the
underlying "git apply" without coalescing.  This was partially corrected
by 7a26e65 (its partial revert, 2009-05-16), but overlapping hunks are
still passed when the patch is edited.

Teach "git apply" the --allow-overlap option that disables a safety
feature that avoids misapplication of patches by not applying patches
to overlapping hunks, and pass this option form "add -p" codepath.

Do not even advertise the option, as this is merely a workaround, and the
correct fix is to make "add -p" correctly coalesce adjacent patch hunks.

Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/apply.c b/builtin/apply.c
index 04f56f850a430cc0f132b6ad38018760eb68a77b..8be1ce539c7282db2376925a0bb6be7bad5fcfe4 100644 (file)
--- a/builtin/apply.c
+++ b/builtin/apply.c
@@ -43,6 +43,7 @@ static int apply = 1;
 static int apply_in_reverse;
 static int apply_with_reject;
 static int apply_verbosely;
+static int allow_overlap;
 static int no_add;
 static const char *fake_ancestor;
 static int line_termination = '\n';
@@ -2430,9 +2431,9 @@ static void update_image(struct image *img,
        memcpy(img->line + applied_pos,
               postimage->line,
               postimage->nr * sizeof(*img->line));
-       for (i = 0; i < postimage->nr; i++)
-               img->line[applied_pos + i].flag |= LINE_PATCHED;
-
+       if (!allow_overlap)
+               for (i = 0; i < postimage->nr; i++)
+                       img->line[applied_pos + i].flag |= LINE_PATCHED;
        img->nr = nr;
 }
 
@@ -3877,6 +3878,8 @@ int cmd_apply(int argc, const char **argv, const char *prefix_)
                        "don't expect at least one line of context"),
                OPT_BOOLEAN(0, "reject", &apply_with_reject,
                        "leave the rejected hunks in corresponding *.rej files"),
+               OPT_BOOLEAN(0, "allow-overlap", &allow_overlap,
+                       "allow overlapping hunks"),
                OPT__VERBOSE(&apply_verbosely, "be verbose"),
                OPT_BIT(0, "inaccurate-eof", &options,
                        "tolerate incorrectly detected missing new-line at the end of file",

diff --git a/git-add--interactive.perl b/git-add--interactive.perl
index fced0ce8eceb1d062c23bbf6b7ab8091907fdbe6..4f08fe704bbaff64613ab07630a71da8bf8bbca0 100755 (executable)
--- a/git-add--interactive.perl
+++ b/git-add--interactive.perl
@@ -705,7 +705,7 @@ sub add_untracked_cmd {
 sub run_git_apply {
        my $cmd = shift;
        my $fh;
-       open $fh, '| git ' . $cmd . " --recount";
+       open $fh, '| git ' . $cmd . " --recount --allow-overlap";
        print $fh @_;
        return close $fh;
 }