From d49d2c7ec4cbe2c0792cf112055a6f5eca79dd63 Mon Sep 17 00:00:00 2001
From: Idan Horowitz <idan.horowitz@gmail.com>
Date: Mon, 24 Jan 2022 23:25:53 +0200
Subject: [PATCH] AK: Add a consume_until(StringView) overload to GenericLexer

This allows us to skip a strlen call.
---
 AK/GenericLexer.cpp                        | 16 ++++++++++++++++
 AK/GenericLexer.h                          |  1 +
 Userland/Libraries/LibCpp/Preprocessor.cpp |  2 +-
 3 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/AK/GenericLexer.cpp b/AK/GenericLexer.cpp
index 7a0372d6a0..05bd6ebb95 100644
--- a/AK/GenericLexer.cpp
+++ b/AK/GenericLexer.cpp
@@ -84,6 +84,22 @@ StringView GenericLexer::consume_until(const char* stop)
     return m_input.substring_view(start, length);
 }
 
+// Consume and return characters until the string `stop` is found
+// The `stop` string is ignored, as it is user-defined
+StringView GenericLexer::consume_until(StringView stop)
+{
+    size_t start = m_index;
+    while (!is_eof() && !next_is(stop))
+        m_index++;
+    size_t length = m_index - start;
+
+    ignore(stop.length());
+
+    if (length == 0)
+        return {};
+    return m_input.substring_view(start, length);
+}
+
 /*
  * Consume a string surrounded by single or double quotes. The returned
  * StringView does not include the quotes. An escape character can be provided
diff --git a/AK/GenericLexer.h b/AK/GenericLexer.h
index 0a44bffc65..37604d2bd5 100644
--- a/AK/GenericLexer.h
+++ b/AK/GenericLexer.h
@@ -113,6 +113,7 @@ public:
     StringView consume_line();
     StringView consume_until(char);
     StringView consume_until(const char*);
+    StringView consume_until(StringView);
     StringView consume_quoted_string(char escape_char = 0);
     String consume_and_unescape_string(char escape_char = '\\');
 
diff --git a/Userland/Libraries/LibCpp/Preprocessor.cpp b/Userland/Libraries/LibCpp/Preprocessor.cpp
index 9cf3cd82fb..f1ade8f27b 100644
--- a/Userland/Libraries/LibCpp/Preprocessor.cpp
+++ b/Userland/Libraries/LibCpp/Preprocessor.cpp
@@ -356,7 +356,7 @@ String Preprocessor::remove_escaped_newlines(StringView value)
     AK::StringBuilder processed_value;
     GenericLexer lexer { value };
     while (!lexer.is_eof()) {
-        processed_value.append(lexer.consume_until("\\\n"));
+        processed_value.append(lexer.consume_until("\\\n"sv));
     }
     return processed_value.to_string();
 }