From bc7b8e2f890e079557c0a3d04059cd42600d0562 Mon Sep 17 00:00:00 2001
From: Vitaly Puzrin <vitaly@rcdesign.ru>
Date: Sun, 26 Oct 2014 07:24:26 +0300
Subject: [PATCH] Perf: regex opts

---
 README.md           |  2 +-
 lib/common/utils.js | 21 +++++++++++++++------
 lib/parser_block.js | 13 +++++++------
 3 files changed, 23 insertions(+), 13 deletions(-)

diff --git a/README.md b/README.md
index 617d96d..f98f7fb 100644
--- a/README.md
+++ b/README.md
@@ -88,7 +88,7 @@ var md = new Remarkable('full');
 By default remarkable is configured to be similar to GFM, but with disabled HTML.
 
 
-### Highligh fenced blocks
+### Highlight fenced blocks
 
 To highlight content of fenced block, assing function to `highlight` option:
 
diff --git a/lib/common/utils.js b/lib/common/utils.js
index 58d6d0e..4eb7901 100644
--- a/lib/common/utils.js
+++ b/lib/common/utils.js
@@ -30,18 +30,27 @@ function assign(obj /*from1, from2, from3, ...*/) {
 }
 
 
-var ESCAPE_TEST_RE = /[&<>"]/;
+var HTML_ESCAPE_TEST_RE = /[&<>"]/;
+var HTML_ESCAPE_REPLACE_RE = /[&<>"]/g;
+var HTML_REPLACEMENTS = {
+  '&': '&amp;',
+  '<': '&lt;',
+  '>': '&gt;',
+  '"': '&quot;'
+};
+
+function replaceUnsafeChar(ch) {
+  return HTML_REPLACEMENTS[ch];
+}
 
 function escapeHtml(str) {
-  if (ESCAPE_TEST_RE.test(str)) {
-    if (str.indexOf('&') >= 0) { str = str.replace(/&/g, '&amp;'); }
-    if (str.indexOf('<') >= 0) { str = str.replace(/</g, '&lt;'); }
-    if (str.indexOf('>') >= 0) { str = str.replace(/>/g, '&gt;'); }
-    if (str.indexOf('"') >= 0) { str = str.replace(/"/g, '&quot;'); }
+  if (HTML_ESCAPE_TEST_RE.test(str)) {
+    return str.replace(HTML_ESCAPE_REPLACE_RE, replaceUnsafeChar);
   }
   return str;
 }
 
+
 var UNESCAPE_MD_RE = /\\([\\!"#$%&'()*+,.\/:;<=>?@[\]^_`{|}~-])/g;
 
 function unescapeMd(str) {
diff --git a/lib/parser_block.js b/lib/parser_block.js
index 7c4d6cc..d750557 100644
--- a/lib/parser_block.js
+++ b/lib/parser_block.js
@@ -104,23 +104,24 @@ ParserBlock.prototype.tokenize = function (state, startLine, endLine) {
   }
 };
 
+var TABS_SCAN_RE = /[\n\t]/g;
+var NEWLINES_RE  = /\r[\n\u0085]|[\u2424\u2028\u0085]/g;
+var SPACES_RE    = /\u00a0/g;
 
 ParserBlock.prototype.parse = function (src, options, env) {
   var state, lineStart = 0, lastTabPos = 0;
 
-  if (!src) { return ''; }
+  if (!src) { return []; }
 
   // Normalize spaces
-  src = src.replace(/\u00a0/g, ' ');
+  src = src.replace(SPACES_RE, ' ');
 
   // Normalize newlines
-  src = src.replace(/\r\n/, '\n');
-  src = src.replace(/\r\u0085/, '\n');
-  src = src.replace(/[\u2424\u2028\u0085]/g, '\n');
+  src = src.replace(NEWLINES_RE, '\n');
 
   // Replace tabs with proper number of spaces (1..4)
   if (src.indexOf('\t') >= 0) {
-    src = src.replace(/[\n\t]/g, function (match, offset) {
+    src = src.replace(TABS_SCAN_RE, function (match, offset) {
       var result;
       if (src.charCodeAt(offset) === 0x0A) {
         lineStart = offset + 1;