From 27070705d3b58d3d4c78a35b89e4532d2e64c37b Mon Sep 17 00:00:00 2001
From: Tony Brix <tony@brix.ninja>
Date: Wed, 21 Oct 2020 09:56:32 -0500
Subject: [PATCH] fix: remove string.repeat for ie11 (#1772)

---
 src/Lexer.js   |  5 +++--
 src/helpers.js | 19 ++++++++++++++++++-
 2 files changed, 21 insertions(+), 3 deletions(-)

diff --git a/src/Lexer.js b/src/Lexer.js
index dc551458..27a740ce 100644
--- a/src/Lexer.js
+++ b/src/Lexer.js
@@ -1,6 +1,7 @@
 const Tokenizer = require('./Tokenizer.js');
 const { defaults } = require('./defaults.js');
 const { block, inline } = require('./rules.js');
+const { repeatString } = require('./helpers.js');
 
 /**
  * smartypants text replacement
@@ -340,14 +341,14 @@ module.exports = class Lexer {
       if (links.length > 0) {
         while ((match = this.tokenizer.rules.inline.reflinkSearch.exec(maskedSrc)) != null) {
           if (links.includes(match[0].slice(match[0].lastIndexOf('[') + 1, -1))) {
-            maskedSrc = maskedSrc.slice(0, match.index) + '[' + 'a'.repeat(match[0].length - 2) + ']' + maskedSrc.slice(this.tokenizer.rules.inline.reflinkSearch.lastIndex);
+            maskedSrc = maskedSrc.slice(0, match.index) + '[' + repeatString('a', match[0].length - 2) + ']' + maskedSrc.slice(this.tokenizer.rules.inline.reflinkSearch.lastIndex);
           }
         }
       }
     }
     // Mask out other blocks
     while ((match = this.tokenizer.rules.inline.blockSkip.exec(maskedSrc)) != null) {
-      maskedSrc = maskedSrc.slice(0, match.index) + '[' + 'a'.repeat(match[0].length - 2) + ']' + maskedSrc.slice(this.tokenizer.rules.inline.blockSkip.lastIndex);
+      maskedSrc = maskedSrc.slice(0, match.index) + '[' + repeatString('a', match[0].length - 2) + ']' + maskedSrc.slice(this.tokenizer.rules.inline.blockSkip.lastIndex);
     }
 
     while (src) {
diff --git a/src/helpers.js b/src/helpers.js
index e5b88932..93c75a1b 100644
--- a/src/helpers.js
+++ b/src/helpers.js
@@ -228,6 +228,22 @@ function checkSanitizeDeprecation(opt) {
   }
 }
 
+// copied from https://stackoverflow.com/a/5450113/806777
+function repeatString(pattern, count) {
+  if (count < 1) {
+    return '';
+  }
+  let result = '';
+  while (count > 1) {
+    if (count & 1) {
+      result += pattern;
+    }
+    count >>= 1;
+    pattern += pattern;
+  }
+  return result + pattern;
+}
+
 module.exports = {
   escape,
   unescape,
@@ -239,5 +255,6 @@ module.exports = {
   splitCells,
   rtrim,
   findClosingBracket,
-  checkSanitizeDeprecation
+  checkSanitizeDeprecation,
+  repeatString
 };