[PATCH 3/4] range-diff: make use of different output indicators

[Stefan Beller <sbeller@google.com>]

This change itself only changes the internal communication and should
have no visible effect to the user. We instruct the diff code that produces
the inner diffs to use X, Y, Z instead of the usual markers for new, old
and context lines

Signed-off-by: Stefan Beller <sbeller@google.com>
---
 range-diff.c | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/range-diff.c b/range-diff.c
index b6b9abac266..6e4192c8e79 100644
--- a/range-diff.c
+++ b/range-diff.c
@@ -38,6 +38,9 @@ static int read_patches(const char *range, struct string_list *list)
 
 	argv_array_pushl(&cp.args, "log", "--no-color", "-p", "--no-merges",
 			"--reverse", "--date-order", "--decorate=no",
+			"--output-indicator-new=X",
+			"--output-indicator-old=Y",
+			"--output-indicator-context=Z",
 			"--no-abbrev-commit", range,
 			NULL);
 	cp.out = -1;
@@ -108,8 +111,18 @@ static int read_patches(const char *range, struct string_list *list)
 			 * we are not interested.
 			 */
 			continue;
-		else
+		else if (line.buf[0] == 'X') {
+			strbuf_addch(&buf, '+');
+			strbuf_add(&buf, line.buf + 1, line.len - 1);
+		} else if (line.buf[0] == 'Y') {
+			strbuf_addch(&buf, '-');
+			strbuf_add(&buf, line.buf + 1, line.len - 1);
+		} else if (line.buf[0] == 'Z') {
+			strbuf_addch(&buf, ' ');
+			strbuf_add(&buf, line.buf + 1, line.len - 1);
+		} else {
 			strbuf_addbuf(&buf, &line);
+		}
 
 		strbuf_addch(&buf, '\n');
 		util->diffsize++;
-- 
2.18.0.865.gffc8e1a3cd6-goog