fixup! built-in add -p: implement the hunk splitting feature

While it is true that the diffs Git generates can only contain comment
lines at the end of a hunk, and really only when indicating that a line
does not end in a Line Feed, comment lines _are_ a valid diff construct.

Let's play it safe by handling those when splitting hunks.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

add-patch.c

@@ -867,6 +867,10 @@ static int split_hunk(struct add_p_state *s, struct file_diff *file_diff,
 
 		if (marker != ' ' || (ch != '-' && ch != '+')) {
 next_hunk_line:
+			/* Comment lines are attached to the previous line */
+			if (ch == '\\')
+				ch = marker ? marker : ' ';
+
 			/* current hunk not done yet */
 			if (ch == ' ')
 				context_line_count++;