Fix formatHTML to work with emojis and HTML tags

markup.js

@@ -168,11 +168,10 @@ class Markup {
   }
 
   static formatHTML (text = '', entities = []) {
-    const chars = [...text]
     const available = [...entities]
     const opened = []
     const result = []
-    for (let offset = 0; offset < chars.length; offset++) {
+    for (let offset = 0; offset < text.length; offset++) {
       while (true) {
         const index = available.findIndex((entity) => entity.offset === offset)
         if (index === -1) {
@@ -213,7 +212,7 @@ class Markup {
         available.splice(index, 1)
       }
 
-      result.push(chars[offset])
+      result.push(escapeHTML(text[offset]))
 
       while (true) {
         const index = opened.findIndex((entity) => entity.offset + entity.length - 1 === offset)
@@ -256,6 +255,18 @@ class Markup {
   }
 }
 
+const escapedChars = {
+  '"': '&quot;',
+  '&': '&amp;',
+  '<': '&lt;',
+  '>': '&gt;'
+}
+
+function escapeHTML (string) {
+  const chars = [...string]
+  return chars.map(char => escapedChars[char] || char).join('')
+}
+
 function buildKeyboard (buttons, options) {
   const result = []
   if (!Array.isArray(buttons)) {

test/markup.js

@@ -222,7 +222,7 @@ test('should generate nested multi markup', (t) => {
   t.deepEqual(markup, '<s>strike<b>bold<u>under</u></b></s>')
 })
 
-test.only('should generate nested multi markup 2', (t) => {
+test('should generate nested multi markup 2', (t) => {
   const markup = Markup.formatHTML('×11 22 333×      ×С123456×                   ×1 22 333×', [
     {
       offset: 1,
@@ -252,3 +252,35 @@ test.only('should generate nested multi markup 2', (t) => {
   ])
   t.deepEqual(markup, '×<b><i>11 22 333</i></b>× <i>     ×С</i><i><b>123456× </b>                  ×1 22 333×</i>')
 })
+
+test('should generate correct markup with emojis', (t) => {
+  const markup = Markup.formatHTML('bold🙂👨‍👩‍👧‍👧 italic', [
+    {
+      offset: 0,
+      length: 6,
+      type: 'bold'
+    },
+    {
+      offset: 18,
+      length: 6,
+      type: 'italic'
+    }
+  ])
+  t.deepEqual(markup, '<b>bold🙂</b>👨‍👩‍👧‍👧 <i>italic</i>')
+})
+
+test('should generate correct markup with HTML tags', (t) => {
+  const markup = Markup.formatHTML('<b>bold</b> <i>italic</i>', [
+    {
+      offset: 3,
+      length: 4,
+      type: 'bold'
+    },
+    {
+      offset: 15,
+      length: 6,
+      type: 'italic'
+    }
+  ])
+  t.deepEqual(markup, '&lt;b&gt;<b>bold</b>&lt;/b&gt; &lt;i&gt;<i>italic</i>&lt;/i&gt;')
+})