From a2a9c4f76ef5a5c32108e36f7c47f8d310322252 Mon Sep 17 00:00:00 2001
From: Krzysztof Kowalczyk <kkowalczyk@gmail.com>
Date: Mon, 29 Jul 2024 23:28:18 +0200
Subject: [PATCH] fix infinite loop with empty list definition (fixes #311)

---
 parser/block.go       | 4 +++-
 parser/parser_test.go | 6 ++++++
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/parser/block.go b/parser/block.go
index 4b7326e..3ef5334 100644
--- a/parser/block.go
+++ b/parser/block.go
@@ -1652,7 +1652,9 @@ func (p *Parser) paragraph(data []byte) int {
 			if p.extensions&DefinitionLists != 0 {
 				if i < len(data)-1 && data[i+1] == ':' {
 					listLen := p.list(data[prev:], ast.ListTypeDefinition, 0, '.')
-					return prev + listLen
+					if listLen > 0 {
+						return prev + listLen
+					}
 				}
 			}
 
diff --git a/parser/parser_test.go b/parser/parser_test.go
index a845041..32b39de 100644
--- a/parser/parser_test.go
+++ b/parser/parser_test.go
@@ -4,6 +4,12 @@ import (
 	"testing"
 )
 
+func TestBug311(t *testing.T) {
+	str := "~~~~\xb4~\x94~\x94~\xd1\r\r:\xb4\x94\x94~\x9f~\xb4~\x94~\x94\x94"
+	p := New()
+	p.Parse([]byte(str))
+}
+
 func TestIsFenceLine(t *testing.T) {
 	tests := []struct {
 		data            []byte