blame: require 0 context lines while finding moved lines with -M

The core part of git blame -M required 1 context line, but
there is no rationale to be found in the code; it causes artifacts
like discussed in the thread:

<http://thread.gmane.org/gmane.comp.version-control.git/255289/>.

<http://permalink.gmane.org/gmane.comp.version-control.git/295795>
sheds some more light on the history of the previous choice.

Signed-off-by: David Kastrup <dak@gnu.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/blame.c b/builtin/blame.c
index 21f42b0b62b81b637f1cc9589cd6c0306a93d05e..a3f68747326836fff7b1f99ce3e5b858f77f97ab 100644 (file)
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -134,7 +134,7 @@ struct progress_info {
        int blamed_lines;
 };
 
-static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
+static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b,
                      xdl_emit_hunk_consume_func_t hunk_func, void *cb_data)
 {
        xpparam_t xpp = {0};
@@ -142,7 +142,6 @@ static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
        xdemitcb_t ecb = {NULL};
 
        xpp.flags = xdl_opts;
-       xecfg.ctxlen = ctxlen;
        xecfg.hunk_func = hunk_func;
        ecb.priv = cb_data;
        return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
@@ -980,7 +979,7 @@ static void pass_blame_to_parent(struct scoreboard *sb,
        fill_origin_blob(&sb->revs->diffopt, target, &file_o);
        num_get_patch++;
 
-       if (diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d))
+       if (diff_hunks(&file_p, &file_o, blame_chunk_cb, &d))
                die("unable to generate diff (%s -> %s)",
                    oid_to_hex(&parent->commit->object.oid),
                    oid_to_hex(&target->commit->object.oid));
@@ -1129,7 +1128,7 @@ static void find_copy_in_blob(struct scoreboard *sb,
         * file_p partially may match that image.
         */
        memset(split, 0, sizeof(struct blame_entry [3]));
-       if (diff_hunks(file_p, &file_o, 1, handle_split_cb, &d))
+       if (diff_hunks(file_p, &file_o, handle_split_cb, &d))
                die("unable to generate diff (%s)",
                    oid_to_hex(&parent->commit->object.oid));
        /* remainder, if any, all match the preimage */