Fixed _ emphasis parsing to conform to spec.

See jgm/CommonMark#317.

1 files changed, 4 insertions, 2 deletions

diff --git a/src/inlines.c b/src/inlines.c
index 3e298de..afe564c 100644
--- a/src/inlines.c
+++ b/src/inlines.c
@@ -301,8 +301,10 @@ scan_delims(subject* subj, unsigned char c, bool * can_open, bool * can_close)
 	                   !utf8proc_is_space(after_char) &&
 	                   !utf8proc_is_punctuation(after_char));
 	if (c == '_') {
-		*can_open = left_flanking && !right_flanking;
-		*can_close = right_flanking && !left_flanking;
+		*can_open = left_flanking &&
+			(!right_flanking || utf8proc_is_punctuation(before_char));
+		*can_close = right_flanking &&
+			(!left_flanking || utf8proc_is_punctuation(after_char));
 	} else if (c == '\'' || c == '"') {
 		*can_open = left_flanking && !right_flanking;
 		*can_close = right_flanking;