From 32f2f7f744c4ec15fb7b8ba243bf76c8c9970b26 Mon Sep 17 00:00:00 2001
From: Joe-noh <goflb.jh@gmail.com>
Date: Wed, 3 May 2017 13:23:32 +0900
Subject: [PATCH 1/2] use original title if slugified title is empty

---
 lib/utils/md-renderer.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/utils/md-renderer.ts b/lib/utils/md-renderer.ts
index 214da61145..ca1525ad68 100644
--- a/lib/utils/md-renderer.ts
+++ b/lib/utils/md-renderer.ts
@@ -53,7 +53,7 @@ export class MdRenderer {
   }
 
   saveHeading(title: string, parent:MarkdownHeading = {id:null, children: this.headings}) :MarkdownHeading {
-    let slug = slugify(title);
+    let slug = slugify(title) || title;
     let id = slug;
     if (parent && parent.id) id = `${parent.id}/${id}`;
     parent.children = parent.children || {};

From 95f7681fee631772e9f151be0765ac0feaab1395 Mon Sep 17 00:00:00 2001
From: Roman Hotsiy <gotsijroman@gmail.com>
Date: Wed, 3 May 2017 11:00:49 +0300
Subject: [PATCH 2/2] chore: add comment

---
 lib/utils/md-renderer.ts | 1 +
 1 file changed, 1 insertion(+)

diff --git a/lib/utils/md-renderer.ts b/lib/utils/md-renderer.ts
index ca1525ad68..bdb5890f82 100644
--- a/lib/utils/md-renderer.ts
+++ b/lib/utils/md-renderer.ts
@@ -53,6 +53,7 @@ export class MdRenderer {
   }
 
   saveHeading(title: string, parent:MarkdownHeading = {id:null, children: this.headings}) :MarkdownHeading {
+    // if title contains some non-ASCII characters (e.g. chinese) slugify returns empty string
     let slug = slugify(title) || title;
     let id = slug;
     if (parent && parent.id) id = `${parent.id}/${id}`;