add escape method

src/Pango.php

@@ -31,7 +31,7 @@ class Pango
         {
             $lines[$index] = sprintf(
                 '<span size="xx-large">%s</span>',
-                htmlentities(
+                self::escape(
                     $h1
                 )
             );
@@ -44,7 +44,7 @@ class Pango
         {
             $lines[$index] = sprintf(
                 '<span size="x-large">%s</span>',
-                htmlentities(
+                self::escape(
                     $h2
                 )
             );
@@ -57,7 +57,7 @@ class Pango
         {
             $lines[$index] = sprintf(
                 '<span size="large">%s</span>',
-                htmlentities(
+                self::escape(
                     $h3
                 )
             );
@@ -70,7 +70,7 @@ class Pango
         {
             if (!in_array($index, $escaped))
             {
-                $lines[$index] = htmlentities(
+                $lines[$index] = self::escape(
                     $line
                 );
             }
@@ -83,4 +83,13 @@ class Pango
             $lines
         );
     }
+
+    public static function escape(
+        string $value
+    ): string
+    {
+        return htmlspecialchars(
+            $value
+        );
+    }
 }