From f4c68eb0a4451004ecc4153266254b1aab28476e Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sun, 17 Jul 2022 21:08:53 +0200
Subject: [PATCH] LibJS: Add PrimitiveString::is_empty() and use it

If we're only interested in whether the string is empty, we can skip the
conversion from UTF-16 to UTF-8.
---
 Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp | 9 +++++++++
 Userland/Libraries/LibJS/Runtime/PrimitiveString.h   | 2 ++
 Userland/Libraries/LibJS/Runtime/Value.cpp           | 2 +-
 3 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp b/Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp
index 4eae78e950..5aa4f0e17f 100644
--- a/Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp
+++ b/Userland/Libraries/LibJS/Runtime/PrimitiveString.cpp
@@ -32,6 +32,15 @@ PrimitiveString::~PrimitiveString()
     vm().string_cache().remove(m_utf8_string);
 }
 
+bool PrimitiveString::is_empty() const
+{
+    if (m_has_utf16_string)
+        return m_utf16_string.is_empty();
+    if (m_has_utf8_string)
+        return m_utf8_string.is_empty();
+    VERIFY_NOT_REACHED();
+}
+
 String const& PrimitiveString::string() const
 {
     if (!m_has_utf8_string) {
diff --git a/Userland/Libraries/LibJS/Runtime/PrimitiveString.h b/Userland/Libraries/LibJS/Runtime/PrimitiveString.h
index 49b136bcd6..1a4f4af0dc 100644
--- a/Userland/Libraries/LibJS/Runtime/PrimitiveString.h
+++ b/Userland/Libraries/LibJS/Runtime/PrimitiveString.h
@@ -24,6 +24,8 @@ public:
     PrimitiveString(PrimitiveString const&) = delete;
     PrimitiveString& operator=(PrimitiveString const&) = delete;
 
+    bool is_empty() const;
+
     String const& string() const;
     bool has_utf8_string() const { return m_has_utf8_string; }
 
diff --git a/Userland/Libraries/LibJS/Runtime/Value.cpp b/Userland/Libraries/LibJS/Runtime/Value.cpp
index c560763156..34fb6c1395 100644
--- a/Userland/Libraries/LibJS/Runtime/Value.cpp
+++ b/Userland/Libraries/LibJS/Runtime/Value.cpp
@@ -382,7 +382,7 @@ bool Value::to_boolean() const
             return false;
         return m_value.as_double != 0;
     case Type::String:
-        return !m_value.as_string->string().is_empty();
+        return !m_value.as_string->is_empty();
     case Type::Symbol:
         return true;
     case Type::BigInt: