whitespace: allocate a few more bits and define WS_INCOMPLETE_LINE

Reserve a few more bits in the diff flags word to be used for future
whitespace rules.  Add WS_INCOMPLETE_LINE without implementing the
behaviour (yet).

Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 6 insertions, 0 deletions

diff --git a/ws.c b/ws.c
index 70acee3337..34a7b4fad2 100644
--- a/ws.c
+++ b/ws.c
@@ -26,6 +26,7 @@ static struct whitespace_rule {
 	{ "blank-at-eol", WS_BLANK_AT_EOL, 0 },
 	{ "blank-at-eof", WS_BLANK_AT_EOF, 0 },
 	{ "tab-in-indent", WS_TAB_IN_INDENT, 0, 1 },
+	{ "incomplete-line", WS_INCOMPLETE_LINE, 0, 0 },
 };
 
 unsigned parse_whitespace_rule(const char *string)
@@ -139,6 +140,11 @@ char *whitespace_error_string(unsigned ws)
 			strbuf_addstr(&err, ", ");
 		strbuf_addstr(&err, "tab in indent");
 	}
+	if (ws & WS_INCOMPLETE_LINE) {
+		if (err.len)
+			strbuf_addstr(&err, ", ");
+		strbuf_addstr(&err, "no newline at the end of file");
+	}
 	return strbuf_detach(&err, NULL);
 }