[PATCH v2] blame: prevent error if range ends past end of file

[Isabella Stephens <istephens@atlassian.com>]

If the -L option is used to specify a line range in git blame, and the
end of the range is past the end of the file, at present git will fail
with a fatal error. This commit prevents such behaviour - instead the
blame is display for any existing lines within the specified range.

Signed-off-by: Isabella Stephens <istephens@atlassian.com>
---
 builtin/blame.c               | 4 ++--
 t/t8003-blame-corner-cases.sh | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/builtin/blame.c b/builtin/blame.c
index 67adaef4d..b5b9db147 100644
--- a/builtin/blame.c
+++ b/builtin/blame.c
@@ -878,13 +878,13 @@ int cmd_blame(int argc, const char **argv, const char *prefix)
 				    nth_line_cb, &sb, lno, anchor,
 				    &bottom, &top, sb.path))
 			usage(blame_usage);
-		if (lno < top || ((lno || bottom) && lno < bottom))
+		if ((lno || bottom) && lno < bottom)
 			die(Q_("file %s has only %lu line",
 			       "file %s has only %lu lines",
 			       lno), path, lno);
 		if (bottom < 1)
 			bottom = 1;
-		if (top < 1)
+		if (top < 1 || lno < top)
 			top = lno;
 		bottom--;
 		range_set_append_unsafe(&ranges, bottom, top);
diff --git a/t/t8003-blame-corner-cases.sh b/t/t8003-blame-corner-cases.sh
index 661f9d430..32b3788fe 100755
--- a/t/t8003-blame-corner-cases.sh
+++ b/t/t8003-blame-corner-cases.sh
@@ -216,8 +216,9 @@ test_expect_success 'blame -L with invalid start' '
 '
 
 test_expect_success 'blame -L with invalid end' '
-	test_must_fail git blame -L1,5 tres 2>errors &&
-	test_i18ngrep "has only 2 lines" errors
+	git blame -L1,5 tres >out &&
+	cat out &&
+	test $(wc -l < out) -eq 2
 '
 
 test_expect_success 'blame parses <end> part of -L' '
-- 
2.14.1