From 6047278f2703fc2e8d4b140046575e1debecf6b6 Mon Sep 17 00:00:00 2001
From: Josh Goldberg <git@joshuakgoldberg.com>
Date: Thu, 31 Oct 2024 00:53:15 -0400
Subject: [PATCH 1/6] fix: correct regexp slash escapes

---
 grammar.pegjs                  | 10 ++++++++--
 parser.js                      | 10 ++++++++--
 tests/fixtures/literalSlash.js | 10 ++++++++++
 tests/queryAttribute.js        | 29 +++++++++++++++++++++++++++++
 4 files changed, 55 insertions(+), 4 deletions(-)
 create mode 100644 tests/fixtures/literalSlash.js

diff --git a/grammar.pegjs b/grammar.pegjs
index a4410a1..cc87d31 100644
--- a/grammar.pegjs
+++ b/grammar.pegjs
@@ -14,6 +14,9 @@
       }
     });
   }
+
+  // https://github.com/estools/esquery/issues/68
+  input = input.replaceAll("\\/", "\\\\x2F");
 }
 
 start
@@ -97,8 +100,11 @@ attr
     path = i:identifierName { return { type: 'literal', value: i }; }
     type = "type(" _ t:[^ )]+ _ ")" { return { type: 'type', value: t.join('') }; }
     flags = [imsu]+
-    regex = "/" d:[^/]+ "/" flgs:flags? { return {
-      type: 'regexp', value: new RegExp(d.join(''), flgs ? flgs.join('') : '') };
+    regex = "/" d:[^/]+ "/" flgs:flags? {
+      const text = d.join('').replaceAll("\\\\x2F", "\\/");
+      return {
+        type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
+      };
     }
 
 field = "." i:identifierName is:("." identifierName)* {
diff --git a/parser.js b/parser.js
index 7ebcabf..90552fa 100644
--- a/parser.js
+++ b/parser.js
@@ -250,8 +250,11 @@
         peg$c75 = peg$literalExpectation("/", false),
         peg$c76 = /^[^\/]/,
         peg$c77 = peg$classExpectation(["/"], true, false),
-        peg$c78 = function(d, flgs) { return {
-              type: 'regexp', value: new RegExp(d.join(''), flgs ? flgs.join('') : '') };
+        peg$c78 = function(d, flgs) {
+              const text = d.join('').replaceAll("\\\\x2F", "\\/");
+              return {
+                type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
+              };
             },
         peg$c79 = function(i, is) {
           return { type: 'field', name: is.reduce(function(memo, p){ return memo + p[0] + p[1]; }, i)};
@@ -2736,6 +2739,9 @@
         });
       }
 
+      // https://github.com/estools/esquery/issues/68
+      input = input.replaceAll("\\/", "\\\\x2F");
+
 
     peg$result = peg$startRuleFunction();
 
diff --git a/tests/fixtures/literalSlash.js b/tests/fixtures/literalSlash.js
new file mode 100644
index 0000000..a5ef922
--- /dev/null
+++ b/tests/fixtures/literalSlash.js
@@ -0,0 +1,10 @@
+import * as esprima from 'esprima';
+
+const parsed = esprima.parse(`
+    var s1 = "foo/bar";
+    var s2 = "foo//bar";
+`);
+
+export default parsed;
+
+
diff --git a/tests/queryAttribute.js b/tests/queryAttribute.js
index 6b5be0a..bb96e01 100644
--- a/tests/queryAttribute.js
+++ b/tests/queryAttribute.js
@@ -2,6 +2,7 @@ import esquery from '../esquery.js';
 import literal from './fixtures/literal.js';
 import conditional from './fixtures/conditional.js';
 import forLoop from './fixtures/forLoop.js';
+import literalSlash from './fixtures/literalSlash.js';
 import simpleFunction from './fixtures/simpleFunction.js';
 import simpleProgram from './fixtures/simpleProgram.js';
 
@@ -160,6 +161,34 @@ describe('Attribute query', function () {
         ]);
     });
 
+    it('single backslash-escaped slash in a regexp', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\/bar/]');
+        assert.includeMembers(matches, [
+            literalSlash.body[0].declarations[0].init
+        ]);
+    });
+
+    it('single encoded slash in a regexp', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\x2Fbar/]');
+        assert.includeMembers(matches, [
+            literalSlash.body[0].declarations[0].init
+        ]);
+    });
+
+    it('double backslash-escaped slash in a regexp', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\/\\/bar/]');
+        assert.includeMembers(matches, [
+            literalSlash.body[1].declarations[0].init
+        ]);
+    });
+
+    it('double backslash-escaped slash in a regexp', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\x2F\\x2Fbar/]');
+        assert.includeMembers(matches, [
+            literalSlash.body[1].declarations[0].init
+        ]);
+    });
+
     it('multiple regexp flags (i and u)', function () {
         const matches = esquery(simpleProgram, '[name=/\\u{61}|[SDFY]/iu]');
         assert.includeMembers(matches, [

From 7d99050559bf5b9c53d9507d133cce3dfd649422 Mon Sep 17 00:00:00 2001
From: Josh Goldberg <git@joshuakgoldberg.com>
Date: Thu, 31 Oct 2024 01:20:56 -0400
Subject: [PATCH 2/6] Failing test cases for non-regex slashes

---
 tests/fixtures/literalSlash.js |  3 +++
 tests/queryAttribute.js        | 14 ++++++++++++++
 2 files changed, 17 insertions(+)

diff --git a/tests/fixtures/literalSlash.js b/tests/fixtures/literalSlash.js
index a5ef922..effce87 100644
--- a/tests/fixtures/literalSlash.js
+++ b/tests/fixtures/literalSlash.js
@@ -3,6 +3,9 @@ import * as esprima from 'esprima';
 const parsed = esprima.parse(`
     var s1 = "foo/bar";
     var s2 = "foo//bar";
+
+    var b1 = "foo\\/bar";
+    var b2 = "foo\\/\\/bar";
 `);
 
 export default parsed;
diff --git a/tests/queryAttribute.js b/tests/queryAttribute.js
index bb96e01..55fb2b0 100644
--- a/tests/queryAttribute.js
+++ b/tests/queryAttribute.js
@@ -161,6 +161,13 @@ describe('Attribute query', function () {
         ]);
     });
 
+    it('single backslash-escaped slash in a literal', function () {
+        const matches = esquery(literalSlash, '[value="foo\\/bar"]');
+        assert.includeMembers(matches, [
+            literalSlash.body[2].declarations[0].init
+        ]);
+    });
+
     it('single backslash-escaped slash in a regexp', function () {
         const matches = esquery(literalSlash, '[value=/foo\\/bar/]');
         assert.includeMembers(matches, [
@@ -175,6 +182,13 @@ describe('Attribute query', function () {
         ]);
     });
 
+    it('single backslash-escaped slash in a literal', function () {
+        const matches = esquery(literalSlash, '[value="foo\\/\\/bar"]');
+        assert.includeMembers(matches, [
+            literalSlash.body[3].declarations[0].init
+        ]);
+    });
+
     it('double backslash-escaped slash in a regexp', function () {
         const matches = esquery(literalSlash, '[value=/foo\\/\\/bar/]');
         assert.includeMembers(matches, [

From d6092de2023533383bfa22e1166363660783476c Mon Sep 17 00:00:00 2001
From: Josh Goldberg <git@joshuakgoldberg.com>
Date: Mon, 4 Nov 2024 14:25:49 -0500
Subject: [PATCH 3/6] account for slashes outside of regex

---
 grammar.pegjs           | 5 ++++-
 parser.js               | 5 ++++-
 tests/queryAttribute.js | 2 +-
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/grammar.pegjs b/grammar.pegjs
index cc87d31..7e2c865 100644
--- a/grammar.pegjs
+++ b/grammar.pegjs
@@ -16,7 +16,9 @@
   }
 
   // https://github.com/estools/esquery/issues/68
-  input = input.replaceAll("\\/", "\\\\x2F");
+  input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
+    return match.replaceAll("\\/", "\\\\x2F");
+  });
 }
 
 start
@@ -101,6 +103,7 @@ attr
     type = "type(" _ t:[^ )]+ _ ")" { return { type: 'type', value: t.join('') }; }
     flags = [imsu]+
     regex = "/" d:[^/]+ "/" flgs:flags? {
+      // https://github.com/estools/esquery/issues/68
       const text = d.join('').replaceAll("\\\\x2F", "\\/");
       return {
         type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
diff --git a/parser.js b/parser.js
index 90552fa..6009be0 100644
--- a/parser.js
+++ b/parser.js
@@ -251,6 +251,7 @@
         peg$c76 = /^[^\/]/,
         peg$c77 = peg$classExpectation(["/"], true, false),
         peg$c78 = function(d, flgs) {
+              // https://github.com/estools/esquery/issues/68
               const text = d.join('').replaceAll("\\\\x2F", "\\/");
               return {
                 type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
@@ -2740,7 +2741,9 @@
       }
 
       // https://github.com/estools/esquery/issues/68
-      input = input.replaceAll("\\/", "\\\\x2F");
+      input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
+        return match.replaceAll("\\/", "\\\\x2F");
+      });
 
 
     peg$result = peg$startRuleFunction();
diff --git a/tests/queryAttribute.js b/tests/queryAttribute.js
index 55fb2b0..2dc2d29 100644
--- a/tests/queryAttribute.js
+++ b/tests/queryAttribute.js
@@ -182,7 +182,7 @@ describe('Attribute query', function () {
         ]);
     });
 
-    it('single backslash-escaped slash in a literal', function () {
+    it('double backslash-escaped slash in a literal', function () {
         const matches = esquery(literalSlash, '[value="foo\\/\\/bar"]');
         assert.includeMembers(matches, [
             literalSlash.body[3].declarations[0].init

From 8af2dfb447789238bb638386e25cea52178d894d Mon Sep 17 00:00:00 2001
From: Josh Goldberg <git@joshuakgoldberg.com>
Date: Mon, 4 Nov 2024 14:28:50 -0500
Subject: [PATCH 4/6] A bit of docs

---
 grammar.pegjs | 1 +
 parser.js     | 1 +
 2 files changed, 2 insertions(+)

diff --git a/grammar.pegjs b/grammar.pegjs
index 7e2c865..b9db0d5 100644
--- a/grammar.pegjs
+++ b/grammar.pegjs
@@ -16,6 +16,7 @@
   }
 
   // https://github.com/estools/esquery/issues/68
+  // Inside all /regexp/ literals, we replace escaped-backslashes with the \x2F equivalent.
   input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
     return match.replaceAll("\\/", "\\\\x2F");
   });
diff --git a/parser.js b/parser.js
index 6009be0..69c9853 100644
--- a/parser.js
+++ b/parser.js
@@ -2741,6 +2741,7 @@
       }
 
       // https://github.com/estools/esquery/issues/68
+      // Inside all /regexp/ literals, we replace escaped-backslashes with the \x2F equivalent.
       input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
         return match.replaceAll("\\/", "\\\\x2F");
       });

From 0ace1a36888c01d9e87356ce1d0183d7dff41251 Mon Sep 17 00:00:00 2001
From: Michael Ficarra <m.ficarra@f5.com>
Date: Tue, 30 Dec 2025 16:34:14 -0700
Subject: [PATCH 5/6] better fix

---
 grammar.pegjs                  |  19 +-
 parser.js                      | 488 +++++++++++++++++++++++++--------
 tests/fixtures/literalSlash.js |   1 -
 tests/queryAttribute.js        |  28 +-
 4 files changed, 393 insertions(+), 143 deletions(-)

diff --git a/grammar.pegjs b/grammar.pegjs
index b9db0d5..b396a31 100644
--- a/grammar.pegjs
+++ b/grammar.pegjs
@@ -14,12 +14,6 @@
       }
     });
   }
-
-  // https://github.com/estools/esquery/issues/68
-  // Inside all /regexp/ literals, we replace escaped-backslashes with the \x2F equivalent.
-  input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
-    return match.replaceAll("\\/", "\\\\x2F");
-  });
 }
 
 start
@@ -103,13 +97,18 @@ attr
     path = i:identifierName { return { type: 'literal', value: i }; }
     type = "type(" _ t:[^ )]+ _ ")" { return { type: 'type', value: t.join('') }; }
     flags = [imsu]+
-    regex = "/" d:[^/]+ "/" flgs:flags? {
-      // https://github.com/estools/esquery/issues/68
-      const text = d.join('').replaceAll("\\\\x2F", "\\/");
+    regex = "/" pattern:(regex_cc / regex_hex_escape / regex_single_char_escape / regex_chars)+ "/" flgs:flags? {
       return {
-        type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
+        type: 'regexp', value: new RegExp(pattern.join(''), flgs ? flgs.join('') : '')
       };
     }
+      regex_cc = "[" cs:([^\]\\] / regex_hex_escape / regex_single_char_escape)+ "]" { return '[' + cs.join('') + ']'; }
+      regex_hex_escape = "\\x" a:[A-Fa-f0-9] b:[A-Fa-f0-9] { return '\\x' + a + b; }
+      regex_single_char_escape = "\\" a:. {
+        let hex = a.charCodeAt(0).toString(16);
+        return '\\x' + (hex.length > 1 ? hex : '0' + hex) ;
+      }
+      regex_chars = cs:[^/\\\[]+ { return cs.join(''); }
 
 field = "." i:identifierName is:("." identifierName)* {
   return { type: 'field', name: is.reduce(function(memo, p){ return memo + p[0] + p[1]; }, i)};
diff --git a/parser.js b/parser.js
index 69c9853..62586d9 100644
--- a/parser.js
+++ b/parser.js
@@ -248,44 +248,55 @@
         peg$c73 = peg$classExpectation(["i", "m", "s", "u"], false, false),
         peg$c74 = "/",
         peg$c75 = peg$literalExpectation("/", false),
-        peg$c76 = /^[^\/]/,
-        peg$c77 = peg$classExpectation(["/"], true, false),
-        peg$c78 = function(d, flgs) {
-              // https://github.com/estools/esquery/issues/68
-              const text = d.join('').replaceAll("\\\\x2F", "\\/");
+        peg$c76 = function(pattern, flgs) {
               return {
-                type: 'regexp', value: new RegExp(text, flgs ? flgs.join('') : '')
+                type: 'regexp', value: new RegExp(pattern.join(''), flgs ? flgs.join('') : '')
               };
             },
-        peg$c79 = function(i, is) {
+        peg$c77 = /^[^\]\\]/,
+        peg$c78 = peg$classExpectation(["]", "\\"], true, false),
+        peg$c79 = function(cs) { return '[' + cs.join('') + ']'; },
+        peg$c80 = "\\x",
+        peg$c81 = peg$literalExpectation("\\x", false),
+        peg$c82 = /^[A-Fa-f0-9]/,
+        peg$c83 = peg$classExpectation([["A", "F"], ["a", "f"], ["0", "9"]], false, false),
+        peg$c84 = function(a, b) { return '\\x' + a + b; },
+        peg$c85 = function(a) {
+                let hex = a.charCodeAt(0).toString(16);
+                return '\\x' + (hex.length > 1 ? hex : '0' + hex) ;
+              },
+        peg$c86 = /^[^\/\\[]/,
+        peg$c87 = peg$classExpectation(["/", "\\", "["], true, false),
+        peg$c88 = function(cs) { return cs.join(''); },
+        peg$c89 = function(i, is) {
           return { type: 'field', name: is.reduce(function(memo, p){ return memo + p[0] + p[1]; }, i)};
         },
-        peg$c80 = ":not(",
-        peg$c81 = peg$literalExpectation(":not(", false),
-        peg$c82 = function(ss) { return { type: 'not', selectors: ss }; },
-        peg$c83 = ":matches(",
-        peg$c84 = peg$literalExpectation(":matches(", false),
-        peg$c85 = function(ss) { return { type: 'matches', selectors: ss }; },
-        peg$c86 = ":is(",
-        peg$c87 = peg$literalExpectation(":is(", false),
-        peg$c88 = ":has(",
-        peg$c89 = peg$literalExpectation(":has(", false),
-        peg$c90 = function(ss) { return { type: 'has', selectors: ss }; },
-        peg$c91 = ":first-child",
-        peg$c92 = peg$literalExpectation(":first-child", false),
-        peg$c93 = function() { return nth(1); },
-        peg$c94 = ":last-child",
-        peg$c95 = peg$literalExpectation(":last-child", false),
-        peg$c96 = function() { return nthLast(1); },
-        peg$c97 = ":nth-child(",
-        peg$c98 = peg$literalExpectation(":nth-child(", false),
-        peg$c99 = function(n) { return nth(parseInt(n.join(''), 10)); },
-        peg$c100 = ":nth-last-child(",
-        peg$c101 = peg$literalExpectation(":nth-last-child(", false),
-        peg$c102 = function(n) { return nthLast(parseInt(n.join(''), 10)); },
-        peg$c103 = ":",
-        peg$c104 = peg$literalExpectation(":", false),
-        peg$c105 = function(c) {
+        peg$c90 = ":not(",
+        peg$c91 = peg$literalExpectation(":not(", false),
+        peg$c92 = function(ss) { return { type: 'not', selectors: ss }; },
+        peg$c93 = ":matches(",
+        peg$c94 = peg$literalExpectation(":matches(", false),
+        peg$c95 = function(ss) { return { type: 'matches', selectors: ss }; },
+        peg$c96 = ":is(",
+        peg$c97 = peg$literalExpectation(":is(", false),
+        peg$c98 = ":has(",
+        peg$c99 = peg$literalExpectation(":has(", false),
+        peg$c100 = function(ss) { return { type: 'has', selectors: ss }; },
+        peg$c101 = ":first-child",
+        peg$c102 = peg$literalExpectation(":first-child", false),
+        peg$c103 = function() { return nth(1); },
+        peg$c104 = ":last-child",
+        peg$c105 = peg$literalExpectation(":last-child", false),
+        peg$c106 = function() { return nthLast(1); },
+        peg$c107 = ":nth-child(",
+        peg$c108 = peg$literalExpectation(":nth-child(", false),
+        peg$c109 = function(n) { return nth(parseInt(n.join(''), 10)); },
+        peg$c110 = ":nth-last-child(",
+        peg$c111 = peg$literalExpectation(":nth-last-child(", false),
+        peg$c112 = function(n) { return nthLast(parseInt(n.join(''), 10)); },
+        peg$c113 = ":",
+        peg$c114 = peg$literalExpectation(":", false),
+        peg$c115 = function(c) {
           return { type: 'class', name: c };
         },
 
@@ -430,7 +441,7 @@
     function peg$parsestart() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 33 + 0,
+      var key    = peg$currPos * 37 + 0,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -479,7 +490,7 @@
     function peg$parse_() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 1,
+      var key    = peg$currPos * 37 + 1,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -515,7 +526,7 @@
     function peg$parseidentifierName() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 2,
+      var key    = peg$currPos * 37 + 2,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -561,7 +572,7 @@
     function peg$parsebinaryOp() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 33 + 3,
+      var key    = peg$currPos * 37 + 3,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -691,7 +702,7 @@
     function peg$parsehasSelectors() {
       var s0, s1, s2, s3, s4, s5, s6, s7;
 
-      var key    = peg$currPos * 33 + 4,
+      var key    = peg$currPos * 37 + 4,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -794,7 +805,7 @@
     function peg$parseselectors() {
       var s0, s1, s2, s3, s4, s5, s6, s7;
 
-      var key    = peg$currPos * 33 + 5,
+      var key    = peg$currPos * 37 + 5,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -897,7 +908,7 @@
     function peg$parsehasSelector() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 6,
+      var key    = peg$currPos * 37 + 6,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -934,7 +945,7 @@
     function peg$parseselector() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 7,
+      var key    = peg$currPos * 37 + 7,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1001,7 +1012,7 @@
     function peg$parsesequence() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 33 + 8,
+      var key    = peg$currPos * 37 + 8,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1053,7 +1064,7 @@
     function peg$parseatom() {
       var s0;
 
-      var key    = peg$currPos * 33 + 9,
+      var key    = peg$currPos * 37 + 9,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1108,7 +1119,7 @@
     function peg$parsewildcard() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 10,
+      var key    = peg$currPos * 37 + 10,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1139,7 +1150,7 @@
     function peg$parseidentifier() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 11,
+      var key    = peg$currPos * 37 + 11,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1182,7 +1193,7 @@
     function peg$parseattr() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 12,
+      var key    = peg$currPos * 37 + 12,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1246,7 +1257,7 @@
     function peg$parseattrOps() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 13,
+      var key    = peg$currPos * 37 + 13,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1304,7 +1315,7 @@
     function peg$parseattrEqOps() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 14,
+      var key    = peg$currPos * 37 + 14,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1353,7 +1364,7 @@
     function peg$parseattrName() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 15,
+      var key    = peg$currPos * 37 + 15,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1432,7 +1443,7 @@
     function peg$parseattrValue() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 16,
+      var key    = peg$currPos * 37 + 16,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1538,7 +1549,7 @@
     function peg$parsestring() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 17,
+      var key    = peg$currPos * 37 + 17,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1780,7 +1791,7 @@
     function peg$parsenumber() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 33 + 18,
+      var key    = peg$currPos * 37 + 18,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1875,7 +1886,7 @@
     function peg$parsepath() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 19,
+      var key    = peg$currPos * 37 + 19,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1900,7 +1911,7 @@
     function peg$parsetype() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 20,
+      var key    = peg$currPos * 37 + 20,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1985,7 +1996,7 @@
     function peg$parseflags() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 21,
+      var key    = peg$currPos * 37 + 21,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2025,7 +2036,7 @@
     function peg$parseregex() {
       var s0, s1, s2, s3, s4;
 
-      var key    = peg$currPos * 33 + 22,
+      var key    = peg$currPos * 37 + 22,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2044,22 +2055,28 @@
       }
       if (s1 !== peg$FAILED) {
         s2 = [];
-        if (peg$c76.test(input.charAt(peg$currPos))) {
-          s3 = input.charAt(peg$currPos);
-          peg$currPos++;
-        } else {
-          s3 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$c77); }
+        s3 = peg$parseregex_cc();
+        if (s3 === peg$FAILED) {
+          s3 = peg$parseregex_hex_escape();
+          if (s3 === peg$FAILED) {
+            s3 = peg$parseregex_single_char_escape();
+            if (s3 === peg$FAILED) {
+              s3 = peg$parseregex_chars();
+            }
+          }
         }
         if (s3 !== peg$FAILED) {
           while (s3 !== peg$FAILED) {
             s2.push(s3);
-            if (peg$c76.test(input.charAt(peg$currPos))) {
-              s3 = input.charAt(peg$currPos);
-              peg$currPos++;
-            } else {
-              s3 = peg$FAILED;
-              if (peg$silentFails === 0) { peg$fail(peg$c77); }
+            s3 = peg$parseregex_cc();
+            if (s3 === peg$FAILED) {
+              s3 = peg$parseregex_hex_escape();
+              if (s3 === peg$FAILED) {
+                s3 = peg$parseregex_single_char_escape();
+                if (s3 === peg$FAILED) {
+                  s3 = peg$parseregex_chars();
+                }
+              }
             }
           }
         } else {
@@ -2080,7 +2097,7 @@
             }
             if (s4 !== peg$FAILED) {
               peg$savedPos = s0;
-              s1 = peg$c78(s2, s4);
+              s1 = peg$c76(s2, s4);
               s0 = s1;
             } else {
               peg$currPos = s0;
@@ -2104,10 +2121,245 @@
       return s0;
     }
 
+    function peg$parseregex_cc() {
+      var s0, s1, s2, s3;
+
+      var key    = peg$currPos * 37 + 23,
+          cached = peg$resultsCache[key];
+
+      if (cached) {
+        peg$currPos = cached.nextPos;
+
+        return cached.result;
+      }
+
+      s0 = peg$currPos;
+      if (input.charCodeAt(peg$currPos) === 91) {
+        s1 = peg$c31;
+        peg$currPos++;
+      } else {
+        s1 = peg$FAILED;
+        if (peg$silentFails === 0) { peg$fail(peg$c32); }
+      }
+      if (s1 !== peg$FAILED) {
+        s2 = [];
+        if (peg$c77.test(input.charAt(peg$currPos))) {
+          s3 = input.charAt(peg$currPos);
+          peg$currPos++;
+        } else {
+          s3 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$c78); }
+        }
+        if (s3 === peg$FAILED) {
+          s3 = peg$parseregex_hex_escape();
+          if (s3 === peg$FAILED) {
+            s3 = peg$parseregex_single_char_escape();
+          }
+        }
+        if (s3 !== peg$FAILED) {
+          while (s3 !== peg$FAILED) {
+            s2.push(s3);
+            if (peg$c77.test(input.charAt(peg$currPos))) {
+              s3 = input.charAt(peg$currPos);
+              peg$currPos++;
+            } else {
+              s3 = peg$FAILED;
+              if (peg$silentFails === 0) { peg$fail(peg$c78); }
+            }
+            if (s3 === peg$FAILED) {
+              s3 = peg$parseregex_hex_escape();
+              if (s3 === peg$FAILED) {
+                s3 = peg$parseregex_single_char_escape();
+              }
+            }
+          }
+        } else {
+          s2 = peg$FAILED;
+        }
+        if (s2 !== peg$FAILED) {
+          if (input.charCodeAt(peg$currPos) === 93) {
+            s3 = peg$c33;
+            peg$currPos++;
+          } else {
+            s3 = peg$FAILED;
+            if (peg$silentFails === 0) { peg$fail(peg$c34); }
+          }
+          if (s3 !== peg$FAILED) {
+            peg$savedPos = s0;
+            s1 = peg$c79(s2);
+            s0 = s1;
+          } else {
+            peg$currPos = s0;
+            s0 = peg$FAILED;
+          }
+        } else {
+          peg$currPos = s0;
+          s0 = peg$FAILED;
+        }
+      } else {
+        peg$currPos = s0;
+        s0 = peg$FAILED;
+      }
+
+      peg$resultsCache[key] = { nextPos: peg$currPos, result: s0 };
+
+      return s0;
+    }
+
+    function peg$parseregex_hex_escape() {
+      var s0, s1, s2, s3;
+
+      var key    = peg$currPos * 37 + 24,
+          cached = peg$resultsCache[key];
+
+      if (cached) {
+        peg$currPos = cached.nextPos;
+
+        return cached.result;
+      }
+
+      s0 = peg$currPos;
+      if (input.substr(peg$currPos, 2) === peg$c80) {
+        s1 = peg$c80;
+        peg$currPos += 2;
+      } else {
+        s1 = peg$FAILED;
+        if (peg$silentFails === 0) { peg$fail(peg$c81); }
+      }
+      if (s1 !== peg$FAILED) {
+        if (peg$c82.test(input.charAt(peg$currPos))) {
+          s2 = input.charAt(peg$currPos);
+          peg$currPos++;
+        } else {
+          s2 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$c83); }
+        }
+        if (s2 !== peg$FAILED) {
+          if (peg$c82.test(input.charAt(peg$currPos))) {
+            s3 = input.charAt(peg$currPos);
+            peg$currPos++;
+          } else {
+            s3 = peg$FAILED;
+            if (peg$silentFails === 0) { peg$fail(peg$c83); }
+          }
+          if (s3 !== peg$FAILED) {
+            peg$savedPos = s0;
+            s1 = peg$c84(s2, s3);
+            s0 = s1;
+          } else {
+            peg$currPos = s0;
+            s0 = peg$FAILED;
+          }
+        } else {
+          peg$currPos = s0;
+          s0 = peg$FAILED;
+        }
+      } else {
+        peg$currPos = s0;
+        s0 = peg$FAILED;
+      }
+
+      peg$resultsCache[key] = { nextPos: peg$currPos, result: s0 };
+
+      return s0;
+    }
+
+    function peg$parseregex_single_char_escape() {
+      var s0, s1, s2;
+
+      var key    = peg$currPos * 37 + 25,
+          cached = peg$resultsCache[key];
+
+      if (cached) {
+        peg$currPos = cached.nextPos;
+
+        return cached.result;
+      }
+
+      s0 = peg$currPos;
+      if (input.charCodeAt(peg$currPos) === 92) {
+        s1 = peg$c52;
+        peg$currPos++;
+      } else {
+        s1 = peg$FAILED;
+        if (peg$silentFails === 0) { peg$fail(peg$c53); }
+      }
+      if (s1 !== peg$FAILED) {
+        if (input.length > peg$currPos) {
+          s2 = input.charAt(peg$currPos);
+          peg$currPos++;
+        } else {
+          s2 = peg$FAILED;
+          if (peg$silentFails === 0) { peg$fail(peg$c54); }
+        }
+        if (s2 !== peg$FAILED) {
+          peg$savedPos = s0;
+          s1 = peg$c85(s2);
+          s0 = s1;
+        } else {
+          peg$currPos = s0;
+          s0 = peg$FAILED;
+        }
+      } else {
+        peg$currPos = s0;
+        s0 = peg$FAILED;
+      }
+
+      peg$resultsCache[key] = { nextPos: peg$currPos, result: s0 };
+
+      return s0;
+    }
+
+    function peg$parseregex_chars() {
+      var s0, s1, s2;
+
+      var key    = peg$currPos * 37 + 26,
+          cached = peg$resultsCache[key];
+
+      if (cached) {
+        peg$currPos = cached.nextPos;
+
+        return cached.result;
+      }
+
+      s0 = peg$currPos;
+      s1 = [];
+      if (peg$c86.test(input.charAt(peg$currPos))) {
+        s2 = input.charAt(peg$currPos);
+        peg$currPos++;
+      } else {
+        s2 = peg$FAILED;
+        if (peg$silentFails === 0) { peg$fail(peg$c87); }
+      }
+      if (s2 !== peg$FAILED) {
+        while (s2 !== peg$FAILED) {
+          s1.push(s2);
+          if (peg$c86.test(input.charAt(peg$currPos))) {
+            s2 = input.charAt(peg$currPos);
+            peg$currPos++;
+          } else {
+            s2 = peg$FAILED;
+            if (peg$silentFails === 0) { peg$fail(peg$c87); }
+          }
+        }
+      } else {
+        s1 = peg$FAILED;
+      }
+      if (s1 !== peg$FAILED) {
+        peg$savedPos = s0;
+        s1 = peg$c88(s1);
+      }
+      s0 = s1;
+
+      peg$resultsCache[key] = { nextPos: peg$currPos, result: s0 };
+
+      return s0;
+    }
+
     function peg$parsefield() {
       var s0, s1, s2, s3, s4, s5, s6;
 
-      var key    = peg$currPos * 33 + 23,
+      var key    = peg$currPos * 37 + 27,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2175,7 +2427,7 @@
           }
           if (s3 !== peg$FAILED) {
             peg$savedPos = s0;
-            s1 = peg$c79(s2, s3);
+            s1 = peg$c89(s2, s3);
             s0 = s1;
           } else {
             peg$currPos = s0;
@@ -2198,7 +2450,7 @@
     function peg$parsenegation() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 24,
+      var key    = peg$currPos * 37 + 28,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2208,12 +2460,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 5) === peg$c80) {
-        s1 = peg$c80;
+      if (input.substr(peg$currPos, 5) === peg$c90) {
+        s1 = peg$c90;
         peg$currPos += 5;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c81); }
+        if (peg$silentFails === 0) { peg$fail(peg$c91); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2231,7 +2483,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c82(s3);
+                s1 = peg$c92(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2262,7 +2514,7 @@
     function peg$parsematches() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 25,
+      var key    = peg$currPos * 37 + 29,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2272,12 +2524,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 9) === peg$c83) {
-        s1 = peg$c83;
+      if (input.substr(peg$currPos, 9) === peg$c93) {
+        s1 = peg$c93;
         peg$currPos += 9;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c84); }
+        if (peg$silentFails === 0) { peg$fail(peg$c94); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2295,7 +2547,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c85(s3);
+                s1 = peg$c95(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2326,7 +2578,7 @@
     function peg$parseis() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 26,
+      var key    = peg$currPos * 37 + 30,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2336,12 +2588,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 4) === peg$c86) {
-        s1 = peg$c86;
+      if (input.substr(peg$currPos, 4) === peg$c96) {
+        s1 = peg$c96;
         peg$currPos += 4;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c87); }
+        if (peg$silentFails === 0) { peg$fail(peg$c97); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2359,7 +2611,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c85(s3);
+                s1 = peg$c95(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2390,7 +2642,7 @@
     function peg$parsehas() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 27,
+      var key    = peg$currPos * 37 + 31,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2400,12 +2652,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 5) === peg$c88) {
-        s1 = peg$c88;
+      if (input.substr(peg$currPos, 5) === peg$c98) {
+        s1 = peg$c98;
         peg$currPos += 5;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c89); }
+        if (peg$silentFails === 0) { peg$fail(peg$c99); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2423,7 +2675,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c90(s3);
+                s1 = peg$c100(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2454,7 +2706,7 @@
     function peg$parsefirstChild() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 28,
+      var key    = peg$currPos * 37 + 32,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2464,16 +2716,16 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 12) === peg$c91) {
-        s1 = peg$c91;
+      if (input.substr(peg$currPos, 12) === peg$c101) {
+        s1 = peg$c101;
         peg$currPos += 12;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c92); }
+        if (peg$silentFails === 0) { peg$fail(peg$c102); }
       }
       if (s1 !== peg$FAILED) {
         peg$savedPos = s0;
-        s1 = peg$c93();
+        s1 = peg$c103();
       }
       s0 = s1;
 
@@ -2485,7 +2737,7 @@
     function peg$parselastChild() {
       var s0, s1;
 
-      var key    = peg$currPos * 33 + 29,
+      var key    = peg$currPos * 37 + 33,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2495,16 +2747,16 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 11) === peg$c94) {
-        s1 = peg$c94;
+      if (input.substr(peg$currPos, 11) === peg$c104) {
+        s1 = peg$c104;
         peg$currPos += 11;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c95); }
+        if (peg$silentFails === 0) { peg$fail(peg$c105); }
       }
       if (s1 !== peg$FAILED) {
         peg$savedPos = s0;
-        s1 = peg$c96();
+        s1 = peg$c106();
       }
       s0 = s1;
 
@@ -2516,7 +2768,7 @@
     function peg$parsenthChild() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 30,
+      var key    = peg$currPos * 37 + 34,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2526,12 +2778,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 11) === peg$c97) {
-        s1 = peg$c97;
+      if (input.substr(peg$currPos, 11) === peg$c107) {
+        s1 = peg$c107;
         peg$currPos += 11;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c98); }
+        if (peg$silentFails === 0) { peg$fail(peg$c108); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2570,7 +2822,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c99(s3);
+                s1 = peg$c109(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2601,7 +2853,7 @@
     function peg$parsenthLastChild() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 33 + 31,
+      var key    = peg$currPos * 37 + 35,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2611,12 +2863,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 16) === peg$c100) {
-        s1 = peg$c100;
+      if (input.substr(peg$currPos, 16) === peg$c110) {
+        s1 = peg$c110;
         peg$currPos += 16;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c101); }
+        if (peg$silentFails === 0) { peg$fail(peg$c111); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2655,7 +2907,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c102(s3);
+                s1 = peg$c112(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2686,7 +2938,7 @@
     function peg$parseclass() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 33 + 32,
+      var key    = peg$currPos * 37 + 36,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2697,17 +2949,17 @@
 
       s0 = peg$currPos;
       if (input.charCodeAt(peg$currPos) === 58) {
-        s1 = peg$c103;
+        s1 = peg$c113;
         peg$currPos++;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c104); }
+        if (peg$silentFails === 0) { peg$fail(peg$c114); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parseidentifierName();
         if (s2 !== peg$FAILED) {
           peg$savedPos = s0;
-          s1 = peg$c105(s2);
+          s1 = peg$c115(s2);
           s0 = s1;
         } else {
           peg$currPos = s0;
@@ -2740,12 +2992,6 @@
         });
       }
 
-      // https://github.com/estools/esquery/issues/68
-      // Inside all /regexp/ literals, we replace escaped-backslashes with the \x2F equivalent.
-      input = input.replaceAll(/\/((?:[^\/\\]|\\.)*?)\//g, (match) => {
-        return match.replaceAll("\\/", "\\\\x2F");
-      });
-
 
     peg$result = peg$startRuleFunction();
 
diff --git a/tests/fixtures/literalSlash.js b/tests/fixtures/literalSlash.js
index effce87..52c9d18 100644
--- a/tests/fixtures/literalSlash.js
+++ b/tests/fixtures/literalSlash.js
@@ -10,4 +10,3 @@ const parsed = esprima.parse(`
 
 export default parsed;
 
-
diff --git a/tests/queryAttribute.js b/tests/queryAttribute.js
index 2dc2d29..f4a39e8 100644
--- a/tests/queryAttribute.js
+++ b/tests/queryAttribute.js
@@ -163,43 +163,49 @@ describe('Attribute query', function () {
 
     it('single backslash-escaped slash in a literal', function () {
         const matches = esquery(literalSlash, '[value="foo\\/bar"]');
-        assert.includeMembers(matches, [
+        assert.sameMembers(matches, [
+            literalSlash.body[0].declarations[0].init,
             literalSlash.body[2].declarations[0].init
         ]);
     });
 
-    it('single backslash-escaped slash in a regexp', function () {
+    it('single backslash-escaped slash in a literal', function () {
         const matches = esquery(literalSlash, '[value=/foo\\/bar/]');
-        assert.includeMembers(matches, [
-            literalSlash.body[0].declarations[0].init
+        assert.sameMembers(matches, [
+            literalSlash.body[0].declarations[0].init,
+            literalSlash.body[2].declarations[0].init
         ]);
     });
 
     it('single encoded slash in a regexp', function () {
         const matches = esquery(literalSlash, '[value=/foo\\x2Fbar/]');
-        assert.includeMembers(matches, [
-            literalSlash.body[0].declarations[0].init
+        assert.sameMembers(matches, [
+            literalSlash.body[0].declarations[0].init,
+            literalSlash.body[2].declarations[0].init
         ]);
     });
 
     it('double backslash-escaped slash in a literal', function () {
         const matches = esquery(literalSlash, '[value="foo\\/\\/bar"]');
-        assert.includeMembers(matches, [
+        assert.sameMembers(matches, [
+            literalSlash.body[1].declarations[0].init,
             literalSlash.body[3].declarations[0].init
         ]);
     });
 
     it('double backslash-escaped slash in a regexp', function () {
         const matches = esquery(literalSlash, '[value=/foo\\/\\/bar/]');
-        assert.includeMembers(matches, [
-            literalSlash.body[1].declarations[0].init
+        assert.sameMembers(matches, [
+            literalSlash.body[1].declarations[0].init,
+            literalSlash.body[3].declarations[0].init
         ]);
     });
 
     it('double backslash-escaped slash in a regexp', function () {
         const matches = esquery(literalSlash, '[value=/foo\\x2F\\x2Fbar/]');
-        assert.includeMembers(matches, [
-            literalSlash.body[1].declarations[0].init
+        assert.sameMembers(matches, [
+            literalSlash.body[1].declarations[0].init,
+            literalSlash.body[3].declarations[0].init
         ]);
     });
 

From 261e905d4ff96d21b6bc0f7577276703426f8298 Mon Sep 17 00:00:00 2001
From: Michael Ficarra <m.ficarra@f5.com>
Date: Wed, 31 Dec 2025 08:23:47 -0700
Subject: [PATCH 6/6] simplify and add more tests

---
 grammar.pegjs           |  12 +-
 parser.js               | 318 +++++++++++++++-------------------------
 tests/queryAttribute.js |  36 ++++-
 3 files changed, 158 insertions(+), 208 deletions(-)

diff --git a/grammar.pegjs b/grammar.pegjs
index b396a31..7d6639f 100644
--- a/grammar.pegjs
+++ b/grammar.pegjs
@@ -97,18 +97,14 @@ attr
     path = i:identifierName { return { type: 'literal', value: i }; }
     type = "type(" _ t:[^ )]+ _ ")" { return { type: 'type', value: t.join('') }; }
     flags = [imsu]+
-    regex = "/" pattern:(regex_cc / regex_hex_escape / regex_single_char_escape / regex_chars)+ "/" flgs:flags? {
+    regex = "/" pattern:(re_character_class / re_escape / re_chars)+ "/" flgs:flags? {
       return {
         type: 'regexp', value: new RegExp(pattern.join(''), flgs ? flgs.join('') : '')
       };
     }
-      regex_cc = "[" cs:([^\]\\] / regex_hex_escape / regex_single_char_escape)+ "]" { return '[' + cs.join('') + ']'; }
-      regex_hex_escape = "\\x" a:[A-Fa-f0-9] b:[A-Fa-f0-9] { return '\\x' + a + b; }
-      regex_single_char_escape = "\\" a:. {
-        let hex = a.charCodeAt(0).toString(16);
-        return '\\x' + (hex.length > 1 ? hex : '0' + hex) ;
-      }
-      regex_chars = cs:[^/\\\[]+ { return cs.join(''); }
+      re_character_class = "[" cs:([^\]\\] / re_escape)+ "]" { return '[' + cs.join('') + ']'; }
+      re_escape = "\\" a:. { return '\\' + a; }
+      re_chars = cs:[^/\\[]+ { return cs.join(''); }
 
 field = "." i:identifierName is:("." identifierName)* {
   return { type: 'field', name: is.reduce(function(memo, p){ return memo + p[0] + p[1]; }, i)};
diff --git a/parser.js b/parser.js
index 62586d9..c6fd741 100644
--- a/parser.js
+++ b/parser.js
@@ -256,47 +256,39 @@
         peg$c77 = /^[^\]\\]/,
         peg$c78 = peg$classExpectation(["]", "\\"], true, false),
         peg$c79 = function(cs) { return '[' + cs.join('') + ']'; },
-        peg$c80 = "\\x",
-        peg$c81 = peg$literalExpectation("\\x", false),
-        peg$c82 = /^[A-Fa-f0-9]/,
-        peg$c83 = peg$classExpectation([["A", "F"], ["a", "f"], ["0", "9"]], false, false),
-        peg$c84 = function(a, b) { return '\\x' + a + b; },
-        peg$c85 = function(a) {
-                let hex = a.charCodeAt(0).toString(16);
-                return '\\x' + (hex.length > 1 ? hex : '0' + hex) ;
-              },
-        peg$c86 = /^[^\/\\[]/,
-        peg$c87 = peg$classExpectation(["/", "\\", "["], true, false),
-        peg$c88 = function(cs) { return cs.join(''); },
-        peg$c89 = function(i, is) {
+        peg$c80 = function(a) { return '\\' + a; },
+        peg$c81 = /^[^\/\\[]/,
+        peg$c82 = peg$classExpectation(["/", "\\", "["], true, false),
+        peg$c83 = function(cs) { return cs.join(''); },
+        peg$c84 = function(i, is) {
           return { type: 'field', name: is.reduce(function(memo, p){ return memo + p[0] + p[1]; }, i)};
         },
-        peg$c90 = ":not(",
-        peg$c91 = peg$literalExpectation(":not(", false),
-        peg$c92 = function(ss) { return { type: 'not', selectors: ss }; },
-        peg$c93 = ":matches(",
-        peg$c94 = peg$literalExpectation(":matches(", false),
-        peg$c95 = function(ss) { return { type: 'matches', selectors: ss }; },
-        peg$c96 = ":is(",
-        peg$c97 = peg$literalExpectation(":is(", false),
-        peg$c98 = ":has(",
-        peg$c99 = peg$literalExpectation(":has(", false),
-        peg$c100 = function(ss) { return { type: 'has', selectors: ss }; },
-        peg$c101 = ":first-child",
-        peg$c102 = peg$literalExpectation(":first-child", false),
-        peg$c103 = function() { return nth(1); },
-        peg$c104 = ":last-child",
-        peg$c105 = peg$literalExpectation(":last-child", false),
-        peg$c106 = function() { return nthLast(1); },
-        peg$c107 = ":nth-child(",
-        peg$c108 = peg$literalExpectation(":nth-child(", false),
-        peg$c109 = function(n) { return nth(parseInt(n.join(''), 10)); },
-        peg$c110 = ":nth-last-child(",
-        peg$c111 = peg$literalExpectation(":nth-last-child(", false),
-        peg$c112 = function(n) { return nthLast(parseInt(n.join(''), 10)); },
-        peg$c113 = ":",
-        peg$c114 = peg$literalExpectation(":", false),
-        peg$c115 = function(c) {
+        peg$c85 = ":not(",
+        peg$c86 = peg$literalExpectation(":not(", false),
+        peg$c87 = function(ss) { return { type: 'not', selectors: ss }; },
+        peg$c88 = ":matches(",
+        peg$c89 = peg$literalExpectation(":matches(", false),
+        peg$c90 = function(ss) { return { type: 'matches', selectors: ss }; },
+        peg$c91 = ":is(",
+        peg$c92 = peg$literalExpectation(":is(", false),
+        peg$c93 = ":has(",
+        peg$c94 = peg$literalExpectation(":has(", false),
+        peg$c95 = function(ss) { return { type: 'has', selectors: ss }; },
+        peg$c96 = ":first-child",
+        peg$c97 = peg$literalExpectation(":first-child", false),
+        peg$c98 = function() { return nth(1); },
+        peg$c99 = ":last-child",
+        peg$c100 = peg$literalExpectation(":last-child", false),
+        peg$c101 = function() { return nthLast(1); },
+        peg$c102 = ":nth-child(",
+        peg$c103 = peg$literalExpectation(":nth-child(", false),
+        peg$c104 = function(n) { return nth(parseInt(n.join(''), 10)); },
+        peg$c105 = ":nth-last-child(",
+        peg$c106 = peg$literalExpectation(":nth-last-child(", false),
+        peg$c107 = function(n) { return nthLast(parseInt(n.join(''), 10)); },
+        peg$c108 = ":",
+        peg$c109 = peg$literalExpectation(":", false),
+        peg$c110 = function(c) {
           return { type: 'class', name: c };
         },
 
@@ -441,7 +433,7 @@
     function peg$parsestart() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 37 + 0,
+      var key    = peg$currPos * 36 + 0,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -490,7 +482,7 @@
     function peg$parse_() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 1,
+      var key    = peg$currPos * 36 + 1,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -526,7 +518,7 @@
     function peg$parseidentifierName() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 2,
+      var key    = peg$currPos * 36 + 2,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -572,7 +564,7 @@
     function peg$parsebinaryOp() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 37 + 3,
+      var key    = peg$currPos * 36 + 3,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -702,7 +694,7 @@
     function peg$parsehasSelectors() {
       var s0, s1, s2, s3, s4, s5, s6, s7;
 
-      var key    = peg$currPos * 37 + 4,
+      var key    = peg$currPos * 36 + 4,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -805,7 +797,7 @@
     function peg$parseselectors() {
       var s0, s1, s2, s3, s4, s5, s6, s7;
 
-      var key    = peg$currPos * 37 + 5,
+      var key    = peg$currPos * 36 + 5,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -908,7 +900,7 @@
     function peg$parsehasSelector() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 6,
+      var key    = peg$currPos * 36 + 6,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -945,7 +937,7 @@
     function peg$parseselector() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 7,
+      var key    = peg$currPos * 36 + 7,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1012,7 +1004,7 @@
     function peg$parsesequence() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 37 + 8,
+      var key    = peg$currPos * 36 + 8,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1064,7 +1056,7 @@
     function peg$parseatom() {
       var s0;
 
-      var key    = peg$currPos * 37 + 9,
+      var key    = peg$currPos * 36 + 9,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1119,7 +1111,7 @@
     function peg$parsewildcard() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 10,
+      var key    = peg$currPos * 36 + 10,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1150,7 +1142,7 @@
     function peg$parseidentifier() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 11,
+      var key    = peg$currPos * 36 + 11,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1193,7 +1185,7 @@
     function peg$parseattr() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 12,
+      var key    = peg$currPos * 36 + 12,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1257,7 +1249,7 @@
     function peg$parseattrOps() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 13,
+      var key    = peg$currPos * 36 + 13,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1315,7 +1307,7 @@
     function peg$parseattrEqOps() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 14,
+      var key    = peg$currPos * 36 + 14,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1364,7 +1356,7 @@
     function peg$parseattrName() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 15,
+      var key    = peg$currPos * 36 + 15,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1443,7 +1435,7 @@
     function peg$parseattrValue() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 16,
+      var key    = peg$currPos * 36 + 16,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1549,7 +1541,7 @@
     function peg$parsestring() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 17,
+      var key    = peg$currPos * 36 + 17,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1791,7 +1783,7 @@
     function peg$parsenumber() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 37 + 18,
+      var key    = peg$currPos * 36 + 18,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1886,7 +1878,7 @@
     function peg$parsepath() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 19,
+      var key    = peg$currPos * 36 + 19,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1911,7 +1903,7 @@
     function peg$parsetype() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 20,
+      var key    = peg$currPos * 36 + 20,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -1996,7 +1988,7 @@
     function peg$parseflags() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 21,
+      var key    = peg$currPos * 36 + 21,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2036,7 +2028,7 @@
     function peg$parseregex() {
       var s0, s1, s2, s3, s4;
 
-      var key    = peg$currPos * 37 + 22,
+      var key    = peg$currPos * 36 + 22,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2055,27 +2047,21 @@
       }
       if (s1 !== peg$FAILED) {
         s2 = [];
-        s3 = peg$parseregex_cc();
+        s3 = peg$parsere_character_class();
         if (s3 === peg$FAILED) {
-          s3 = peg$parseregex_hex_escape();
+          s3 = peg$parsere_escape();
           if (s3 === peg$FAILED) {
-            s3 = peg$parseregex_single_char_escape();
-            if (s3 === peg$FAILED) {
-              s3 = peg$parseregex_chars();
-            }
+            s3 = peg$parsere_chars();
           }
         }
         if (s3 !== peg$FAILED) {
           while (s3 !== peg$FAILED) {
             s2.push(s3);
-            s3 = peg$parseregex_cc();
+            s3 = peg$parsere_character_class();
             if (s3 === peg$FAILED) {
-              s3 = peg$parseregex_hex_escape();
+              s3 = peg$parsere_escape();
               if (s3 === peg$FAILED) {
-                s3 = peg$parseregex_single_char_escape();
-                if (s3 === peg$FAILED) {
-                  s3 = peg$parseregex_chars();
-                }
+                s3 = peg$parsere_chars();
               }
             }
           }
@@ -2121,10 +2107,10 @@
       return s0;
     }
 
-    function peg$parseregex_cc() {
+    function peg$parsere_character_class() {
       var s0, s1, s2, s3;
 
-      var key    = peg$currPos * 37 + 23,
+      var key    = peg$currPos * 36 + 23,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2151,10 +2137,7 @@
           if (peg$silentFails === 0) { peg$fail(peg$c78); }
         }
         if (s3 === peg$FAILED) {
-          s3 = peg$parseregex_hex_escape();
-          if (s3 === peg$FAILED) {
-            s3 = peg$parseregex_single_char_escape();
-          }
+          s3 = peg$parsere_escape();
         }
         if (s3 !== peg$FAILED) {
           while (s3 !== peg$FAILED) {
@@ -2167,10 +2150,7 @@
               if (peg$silentFails === 0) { peg$fail(peg$c78); }
             }
             if (s3 === peg$FAILED) {
-              s3 = peg$parseregex_hex_escape();
-              if (s3 === peg$FAILED) {
-                s3 = peg$parseregex_single_char_escape();
-              }
+              s3 = peg$parsere_escape();
             }
           }
         } else {
@@ -2206,68 +2186,10 @@
       return s0;
     }
 
-    function peg$parseregex_hex_escape() {
-      var s0, s1, s2, s3;
-
-      var key    = peg$currPos * 37 + 24,
-          cached = peg$resultsCache[key];
-
-      if (cached) {
-        peg$currPos = cached.nextPos;
-
-        return cached.result;
-      }
-
-      s0 = peg$currPos;
-      if (input.substr(peg$currPos, 2) === peg$c80) {
-        s1 = peg$c80;
-        peg$currPos += 2;
-      } else {
-        s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c81); }
-      }
-      if (s1 !== peg$FAILED) {
-        if (peg$c82.test(input.charAt(peg$currPos))) {
-          s2 = input.charAt(peg$currPos);
-          peg$currPos++;
-        } else {
-          s2 = peg$FAILED;
-          if (peg$silentFails === 0) { peg$fail(peg$c83); }
-        }
-        if (s2 !== peg$FAILED) {
-          if (peg$c82.test(input.charAt(peg$currPos))) {
-            s3 = input.charAt(peg$currPos);
-            peg$currPos++;
-          } else {
-            s3 = peg$FAILED;
-            if (peg$silentFails === 0) { peg$fail(peg$c83); }
-          }
-          if (s3 !== peg$FAILED) {
-            peg$savedPos = s0;
-            s1 = peg$c84(s2, s3);
-            s0 = s1;
-          } else {
-            peg$currPos = s0;
-            s0 = peg$FAILED;
-          }
-        } else {
-          peg$currPos = s0;
-          s0 = peg$FAILED;
-        }
-      } else {
-        peg$currPos = s0;
-        s0 = peg$FAILED;
-      }
-
-      peg$resultsCache[key] = { nextPos: peg$currPos, result: s0 };
-
-      return s0;
-    }
-
-    function peg$parseregex_single_char_escape() {
+    function peg$parsere_escape() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 25,
+      var key    = peg$currPos * 36 + 24,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2294,7 +2216,7 @@
         }
         if (s2 !== peg$FAILED) {
           peg$savedPos = s0;
-          s1 = peg$c85(s2);
+          s1 = peg$c80(s2);
           s0 = s1;
         } else {
           peg$currPos = s0;
@@ -2310,10 +2232,10 @@
       return s0;
     }
 
-    function peg$parseregex_chars() {
+    function peg$parsere_chars() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 26,
+      var key    = peg$currPos * 36 + 25,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2324,22 +2246,22 @@
 
       s0 = peg$currPos;
       s1 = [];
-      if (peg$c86.test(input.charAt(peg$currPos))) {
+      if (peg$c81.test(input.charAt(peg$currPos))) {
         s2 = input.charAt(peg$currPos);
         peg$currPos++;
       } else {
         s2 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c87); }
+        if (peg$silentFails === 0) { peg$fail(peg$c82); }
       }
       if (s2 !== peg$FAILED) {
         while (s2 !== peg$FAILED) {
           s1.push(s2);
-          if (peg$c86.test(input.charAt(peg$currPos))) {
+          if (peg$c81.test(input.charAt(peg$currPos))) {
             s2 = input.charAt(peg$currPos);
             peg$currPos++;
           } else {
             s2 = peg$FAILED;
-            if (peg$silentFails === 0) { peg$fail(peg$c87); }
+            if (peg$silentFails === 0) { peg$fail(peg$c82); }
           }
         }
       } else {
@@ -2347,7 +2269,7 @@
       }
       if (s1 !== peg$FAILED) {
         peg$savedPos = s0;
-        s1 = peg$c88(s1);
+        s1 = peg$c83(s1);
       }
       s0 = s1;
 
@@ -2359,7 +2281,7 @@
     function peg$parsefield() {
       var s0, s1, s2, s3, s4, s5, s6;
 
-      var key    = peg$currPos * 37 + 27,
+      var key    = peg$currPos * 36 + 26,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2427,7 +2349,7 @@
           }
           if (s3 !== peg$FAILED) {
             peg$savedPos = s0;
-            s1 = peg$c89(s2, s3);
+            s1 = peg$c84(s2, s3);
             s0 = s1;
           } else {
             peg$currPos = s0;
@@ -2450,7 +2372,7 @@
     function peg$parsenegation() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 28,
+      var key    = peg$currPos * 36 + 27,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2460,12 +2382,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 5) === peg$c90) {
-        s1 = peg$c90;
+      if (input.substr(peg$currPos, 5) === peg$c85) {
+        s1 = peg$c85;
         peg$currPos += 5;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c91); }
+        if (peg$silentFails === 0) { peg$fail(peg$c86); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2483,7 +2405,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c92(s3);
+                s1 = peg$c87(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2514,7 +2436,7 @@
     function peg$parsematches() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 29,
+      var key    = peg$currPos * 36 + 28,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2524,12 +2446,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 9) === peg$c93) {
-        s1 = peg$c93;
+      if (input.substr(peg$currPos, 9) === peg$c88) {
+        s1 = peg$c88;
         peg$currPos += 9;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c94); }
+        if (peg$silentFails === 0) { peg$fail(peg$c89); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2547,7 +2469,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c95(s3);
+                s1 = peg$c90(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2578,7 +2500,7 @@
     function peg$parseis() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 30,
+      var key    = peg$currPos * 36 + 29,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2588,12 +2510,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 4) === peg$c96) {
-        s1 = peg$c96;
+      if (input.substr(peg$currPos, 4) === peg$c91) {
+        s1 = peg$c91;
         peg$currPos += 4;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c97); }
+        if (peg$silentFails === 0) { peg$fail(peg$c92); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2611,7 +2533,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c95(s3);
+                s1 = peg$c90(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2642,7 +2564,7 @@
     function peg$parsehas() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 31,
+      var key    = peg$currPos * 36 + 30,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2652,12 +2574,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 5) === peg$c98) {
-        s1 = peg$c98;
+      if (input.substr(peg$currPos, 5) === peg$c93) {
+        s1 = peg$c93;
         peg$currPos += 5;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c99); }
+        if (peg$silentFails === 0) { peg$fail(peg$c94); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2675,7 +2597,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c100(s3);
+                s1 = peg$c95(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2706,7 +2628,7 @@
     function peg$parsefirstChild() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 32,
+      var key    = peg$currPos * 36 + 31,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2716,16 +2638,16 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 12) === peg$c101) {
-        s1 = peg$c101;
+      if (input.substr(peg$currPos, 12) === peg$c96) {
+        s1 = peg$c96;
         peg$currPos += 12;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c102); }
+        if (peg$silentFails === 0) { peg$fail(peg$c97); }
       }
       if (s1 !== peg$FAILED) {
         peg$savedPos = s0;
-        s1 = peg$c103();
+        s1 = peg$c98();
       }
       s0 = s1;
 
@@ -2737,7 +2659,7 @@
     function peg$parselastChild() {
       var s0, s1;
 
-      var key    = peg$currPos * 37 + 33,
+      var key    = peg$currPos * 36 + 32,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2747,16 +2669,16 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 11) === peg$c104) {
-        s1 = peg$c104;
+      if (input.substr(peg$currPos, 11) === peg$c99) {
+        s1 = peg$c99;
         peg$currPos += 11;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c105); }
+        if (peg$silentFails === 0) { peg$fail(peg$c100); }
       }
       if (s1 !== peg$FAILED) {
         peg$savedPos = s0;
-        s1 = peg$c106();
+        s1 = peg$c101();
       }
       s0 = s1;
 
@@ -2768,7 +2690,7 @@
     function peg$parsenthChild() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 34,
+      var key    = peg$currPos * 36 + 33,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2778,12 +2700,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 11) === peg$c107) {
-        s1 = peg$c107;
+      if (input.substr(peg$currPos, 11) === peg$c102) {
+        s1 = peg$c102;
         peg$currPos += 11;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c108); }
+        if (peg$silentFails === 0) { peg$fail(peg$c103); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2822,7 +2744,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c109(s3);
+                s1 = peg$c104(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2853,7 +2775,7 @@
     function peg$parsenthLastChild() {
       var s0, s1, s2, s3, s4, s5;
 
-      var key    = peg$currPos * 37 + 35,
+      var key    = peg$currPos * 36 + 34,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2863,12 +2785,12 @@
       }
 
       s0 = peg$currPos;
-      if (input.substr(peg$currPos, 16) === peg$c110) {
-        s1 = peg$c110;
+      if (input.substr(peg$currPos, 16) === peg$c105) {
+        s1 = peg$c105;
         peg$currPos += 16;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c111); }
+        if (peg$silentFails === 0) { peg$fail(peg$c106); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parse_();
@@ -2907,7 +2829,7 @@
               }
               if (s5 !== peg$FAILED) {
                 peg$savedPos = s0;
-                s1 = peg$c112(s3);
+                s1 = peg$c107(s3);
                 s0 = s1;
               } else {
                 peg$currPos = s0;
@@ -2938,7 +2860,7 @@
     function peg$parseclass() {
       var s0, s1, s2;
 
-      var key    = peg$currPos * 37 + 36,
+      var key    = peg$currPos * 36 + 35,
           cached = peg$resultsCache[key];
 
       if (cached) {
@@ -2949,17 +2871,17 @@
 
       s0 = peg$currPos;
       if (input.charCodeAt(peg$currPos) === 58) {
-        s1 = peg$c113;
+        s1 = peg$c108;
         peg$currPos++;
       } else {
         s1 = peg$FAILED;
-        if (peg$silentFails === 0) { peg$fail(peg$c114); }
+        if (peg$silentFails === 0) { peg$fail(peg$c109); }
       }
       if (s1 !== peg$FAILED) {
         s2 = peg$parseidentifierName();
         if (s2 !== peg$FAILED) {
           peg$savedPos = s0;
-          s1 = peg$c115(s2);
+          s1 = peg$c110(s2);
           s0 = s1;
         } else {
           peg$currPos = s0;
diff --git a/tests/queryAttribute.js b/tests/queryAttribute.js
index f4a39e8..e72854f 100644
--- a/tests/queryAttribute.js
+++ b/tests/queryAttribute.js
@@ -177,7 +177,15 @@ describe('Attribute query', function () {
         ]);
     });
 
-    it('single encoded slash in a regexp', function () {
+    it('single slash in a regexp character class', function () {
+        const matches = esquery(literalSlash, '[value=/foo[/]bar/]');
+        assert.sameMembers(matches, [
+            literalSlash.body[0].declarations[0].init,
+            literalSlash.body[2].declarations[0].init
+        ]);
+    });
+
+    it('single encoded slash in a regexp (\\x2F)', function () {
         const matches = esquery(literalSlash, '[value=/foo\\x2Fbar/]');
         assert.sameMembers(matches, [
             literalSlash.body[0].declarations[0].init,
@@ -185,6 +193,14 @@ describe('Attribute query', function () {
         ]);
     });
 
+    it('single encoded slash in a regexp (\\u002F)', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\u002Fbar/]');
+        assert.sameMembers(matches, [
+            literalSlash.body[0].declarations[0].init,
+            literalSlash.body[2].declarations[0].init
+        ]);
+    });
+
     it('double backslash-escaped slash in a literal', function () {
         const matches = esquery(literalSlash, '[value="foo\\/\\/bar"]');
         assert.sameMembers(matches, [
@@ -201,7 +217,15 @@ describe('Attribute query', function () {
         ]);
     });
 
-    it('double backslash-escaped slash in a regexp', function () {
+    it('double slash in a regexp character class', function () {
+        const matches = esquery(literalSlash, '[value=/foo[/][/]bar/]');
+        assert.sameMembers(matches, [
+            literalSlash.body[1].declarations[0].init,
+            literalSlash.body[3].declarations[0].init
+        ]);
+    });
+
+    it('double backslash-escaped slash in a regexp (\\x2F)', function () {
         const matches = esquery(literalSlash, '[value=/foo\\x2F\\x2Fbar/]');
         assert.sameMembers(matches, [
             literalSlash.body[1].declarations[0].init,
@@ -209,6 +233,14 @@ describe('Attribute query', function () {
         ]);
     });
 
+    it('double backslash-escaped slash in a regexp (\\u002F)', function () {
+        const matches = esquery(literalSlash, '[value=/foo\\u002F\\u002Fbar/]');
+        assert.sameMembers(matches, [
+            literalSlash.body[1].declarations[0].init,
+            literalSlash.body[3].declarations[0].init
+        ]);
+    });
+
     it('multiple regexp flags (i and u)', function () {
         const matches = esquery(simpleProgram, '[name=/\\u{61}|[SDFY]/iu]');
         assert.includeMembers(matches, [