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>

David Kastrup committed May 28, 2016 at 11:13 UTC 17a07e2ae2de36cadfac2349189e0c65e1c08d07
1 file changed +3 -4
builtin/blame.c
+3 -4
@@ -134,7 +134,7 @@ struct progress_info {
134 int blamed_lines;
135 };
136
137 -static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
137 +static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b,
138 xdl_emit_hunk_consume_func_t hunk_func, void *cb_data)
139 {
140 xpparam_t xpp = {0};
@@ -142,7 +142,6 @@ static int diff_hunks(mmfile_t *file_a, mmfile_t *file_b, long ctxlen,
142 xdemitcb_t ecb = {NULL};
143
144 xpp.flags = xdl_opts;
145 - xecfg.ctxlen = ctxlen;
145 xecfg.hunk_func = hunk_func;
146 ecb.priv = cb_data;
147 return xdi_diff(file_a, file_b, &xpp, &xecfg, &ecb);
@@ -980,7 +979,7 @@ static void pass_blame_to_parent(struct scoreboard *sb,
979 fill_origin_blob(&sb->revs->diffopt, target, &file_o);
980 num_get_patch++;
981
983 - if (diff_hunks(&file_p, &file_o, 0, blame_chunk_cb, &d))
982 + if (diff_hunks(&file_p, &file_o, blame_chunk_cb, &d))
983 die("unable to generate diff (%s -> %s)",
984 oid_to_hex(&parent->commit->object.oid),
985 oid_to_hex(&target->commit->object.oid));
@@ -1129,7 +1128,7 @@ static void find_copy_in_blob(struct scoreboard *sb,
1128 * file_p partially may match that image.
1129 */
1130 memset(split, 0, sizeof(struct blame_entry [3]));
1132 - if (diff_hunks(file_p, &file_o, 1, handle_split_cb, &d))
1131 + if (diff_hunks(file_p, &file_o, handle_split_cb, &d))
1132 die("unable to generate diff (%s)",
1133 oid_to_hex(&parent->commit->object.oid));
1134 /* remainder, if any, all match the preimage */