From 65003241e40cb51605a0e0fcfb5203356af79b6a Mon Sep 17 00:00:00 2001
From: Timothy Flynn <trflynn89@pm.me>
Date: Tue, 6 Jul 2021 11:09:46 -0400
Subject: [PATCH] LibRegex: Allow dollar signs in ECMA262 named capture groups

Fixes 1 test262 test.
---
 Tests/LibRegex/Regex.cpp                      | 21 +++++++++++++++++++
 .../String/String.prototype.replace.js        |  3 +++
 Userland/Libraries/LibRegex/RegexParser.cpp   |  2 +-
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/Tests/LibRegex/Regex.cpp b/Tests/LibRegex/Regex.cpp
index 9656608571..20581b3a8f 100644
--- a/Tests/LibRegex/Regex.cpp
+++ b/Tests/LibRegex/Regex.cpp
@@ -422,6 +422,27 @@ TEST_CASE(named_capture_group)
     EXPECT_EQ(result.named_capture_group_matches.at(1).ensure("Test").view, "0");
 }
 
+TEST_CASE(ecma262_named_capture_group_with_dollar_sign)
+{
+    Regex<ECMA262> re("[a-zA-Z]*=(?<$Test$>[0-9]*)");
+    RegexResult result;
+
+    if constexpr (REGEX_DEBUG) {
+        RegexDebug regex_dbg(stderr);
+        regex_dbg.print_raw_bytecode(re);
+        regex_dbg.print_header();
+        regex_dbg.print_bytecode(re);
+    }
+
+    String haystack = "[Window]\nOpacity=255\nAudibleBeep=0\n";
+    EXPECT_EQ(re.search(haystack, result, ECMAScriptFlags::Multiline), true);
+    EXPECT_EQ(result.count, 2u);
+    EXPECT_EQ(result.matches.at(0).view, "Opacity=255");
+    EXPECT_EQ(result.named_capture_group_matches.at(0).ensure("$Test$").view, "255");
+    EXPECT_EQ(result.matches.at(1).view, "AudibleBeep=0");
+    EXPECT_EQ(result.named_capture_group_matches.at(1).ensure("$Test$").view, "0");
+}
+
 TEST_CASE(a_star)
 {
     Regex<PosixExtended> re("a*");
diff --git a/Userland/Libraries/LibJS/Tests/builtins/String/String.prototype.replace.js b/Userland/Libraries/LibJS/Tests/builtins/String/String.prototype.replace.js
index 16d481c9f8..90e306bccb 100644
--- a/Userland/Libraries/LibJS/Tests/builtins/String/String.prototype.replace.js
+++ b/Userland/Libraries/LibJS/Tests/builtins/String/String.prototype.replace.js
@@ -138,6 +138,9 @@ test("replacement with substitution", () => {
     expect("abc".replace(/(?<val1>a)b(?<val2>c)/, "$<val1>")).toBe("a");
     expect("abc".replace(/(?<val1>a)b(?<val2>c)/, "$<val2>")).toBe("c");
     expect("abc".replace(/(?<val1>a)b(?<val2>c)/, "$<val2>b$<val1>")).toBe("cba");
+
+    expect(/(?<𝒜>b)/u[Symbol.replace]("abc", "d$<𝒜>$`")).toBe("adbac");
+    expect(/(?<$𐒤>b)/gu[Symbol.replace]("abc", "$'$<$𐒤>d")).toBe("acbdc");
 });
 
 test("replacement with substitution and 'groups' coerced to an object", () => {
diff --git a/Userland/Libraries/LibRegex/RegexParser.cpp b/Userland/Libraries/LibRegex/RegexParser.cpp
index 1c6a78b072..a3a271036f 100644
--- a/Userland/Libraries/LibRegex/RegexParser.cpp
+++ b/Userland/Libraries/LibRegex/RegexParser.cpp
@@ -1625,7 +1625,7 @@ StringView ECMA262Parser::read_capture_group_specifier(bool take_starting_angle_
 
     auto start_token = m_parser_state.current_token;
     size_t offset = 0;
-    while (match(TokenType::Char)) {
+    while (match(TokenType::Char) || match(TokenType::Dollar)) {
         auto c = m_parser_state.current_token.value();
         if (c == ">")
             break;