From 60858b671907c49c77afd520ecec43e15c5ee544 Mon Sep 17 00:00:00 2001
From: Raymond Hill <rhill@raymondhill.net>
Date: Mon, 15 Apr 2019 18:56:28 -0400
Subject: [PATCH] Fix handling of backslashes in string expressions for
 `:has-text()`

---
 src/js/static-ext-filtering.js | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/src/js/static-ext-filtering.js b/src/js/static-ext-filtering.js
index 7e0bef59c..e8c8a9535 100644
--- a/src/js/static-ext-filtering.js
+++ b/src/js/static-ext-filtering.js
@@ -173,14 +173,17 @@
             ')\\('
         ].join(''));
 
-        const reEscapeRegex = /[.*+?^${}()|[\]\\]/g,
-            reNeedScope = /^\s*[+>~]/,
-            reIsDanglingSelector = /(?:[+>~]\s*|\s+)$/;
+        const reEatBackslashes = /\\([()])/g;
+        const reEscapeRegex = /[.*+?^${}()|[\]\\]/g;
+        const reNeedScope = /^\s*[+>~]/;
+        const reIsDanglingSelector = /(?:[+>~]\s*|\s+)$/;
 
         const regexToRawValue = new Map();
         let lastProceduralSelector = '',
             lastProceduralSelectorCompiled;
 
+        // When dealing with literal text, we must first eat _some_
+        // backslash characters.
         const compileText = function(s) {
             const match = reParseRegexLiteral.exec(s);
             let regexDetails;
@@ -191,7 +194,8 @@
                     regexDetails = [ regexDetails, match[2] ];
                 }
             } else {
-                regexDetails = s.replace(reEscapeRegex, '\\$&');
+                regexDetails = s.replace(reEatBackslashes, '$1')
+                                .replace(reEscapeRegex, '\\$&');
                 regexToRawValue.set(regexDetails, s);
             }
             return regexDetails;