LibJS: Do not use the $ special character in file names

The dollar sign is a special character in POSIX shells and in the Ninja
build file format. If the file name contains a `$`, something goes wrong
in the escaping/unescaping of this symbol, and CMake/GCC/Clang generate
invalid dependency files where not all instances of `$` are escaped
properly. Because of this, Ninja fails to rebuild `$262Object.cpp` if
the headers included by it have changed.

Stale `$262Object.cpp.o` files have been the cause of mysterious crashes
multiple times which only go away after doing a clean build. Let's
prevent these from happening again by removing the `$` from the
filename.

Userland/Libraries/LibJS/Contrib/Test262/262Object.cpp

@@ -0,0 +1,119 @@
+/*
+ * Copyright (c) 2021-2022, Linus Groh <linusg@serenityos.org>
+ * Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+// NOTE: This file is not named $262Object.cpp because dollar signs in file names cause issues with some build tools.
+
+#include <AK/TypeCasts.h>
+#include <LibJS/Bytecode/Interpreter.h>
+#include <LibJS/Contrib/Test262/262Object.h>
+#include <LibJS/Contrib/Test262/AgentObject.h>
+#include <LibJS/Contrib/Test262/GlobalObject.h>
+#include <LibJS/Contrib/Test262/IsHTMLDDA.h>
+#include <LibJS/Heap/Cell.h>
+#include <LibJS/Interpreter.h>
+#include <LibJS/Runtime/ArrayBuffer.h>
+#include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/Object.h>
+#include <LibJS/Script.h>
+
+namespace JS::Test262 {
+
+$262Object::$262Object(Realm& realm)
+    : Object(Object::ConstructWithoutPrototypeTag::Tag, realm)
+{
+}
+
+ThrowCompletionOr<void> $262Object::initialize(Realm& realm)
+{
+    MUST_OR_THROW_OOM(Base::initialize(realm));
+
+    m_agent = MUST_OR_THROW_OOM(vm().heap().allocate<AgentObject>(realm, realm));
+    m_is_htmldda = MUST_OR_THROW_OOM(vm().heap().allocate<IsHTMLDDA>(realm, realm));
+
+    u8 attr = Attribute::Writable | Attribute::Configurable;
+    define_native_function(realm, "clearKeptObjects", clear_kept_objects, 0, attr);
+    define_native_function(realm, "createRealm", create_realm, 0, attr);
+    define_native_function(realm, "detachArrayBuffer", detach_array_buffer, 1, attr);
+    define_native_function(realm, "evalScript", eval_script, 1, attr);
+
+    define_direct_property("agent", m_agent, attr);
+    define_direct_property("gc", realm.global_object().get_without_side_effects("gc"), attr);
+    define_direct_property("global", &realm.global_object(), attr);
+    define_direct_property("IsHTMLDDA", m_is_htmldda, attr);
+
+    return {};
+}
+
+void $262Object::visit_edges(Cell::Visitor& visitor)
+{
+    Base::visit_edges(visitor);
+    visitor.visit(m_agent);
+    visitor.visit(m_is_htmldda);
+}
+
+JS_DEFINE_NATIVE_FUNCTION($262Object::clear_kept_objects)
+{
+    vm.finish_execution_generation();
+    return js_undefined();
+}
+
+JS_DEFINE_NATIVE_FUNCTION($262Object::create_realm)
+{
+    auto realm = MUST_OR_THROW_OOM(Realm::create(vm));
+    auto realm_global_object = vm.heap().allocate_without_realm<GlobalObject>(*realm);
+    VERIFY(realm_global_object);
+    realm->set_global_object(realm_global_object, nullptr);
+    set_default_global_bindings(*realm);
+    MUST_OR_THROW_OOM(realm_global_object->initialize(*realm));
+    return Value(realm_global_object->$262());
+}
+
+JS_DEFINE_NATIVE_FUNCTION($262Object::detach_array_buffer)
+{
+    auto array_buffer = vm.argument(0);
+    if (!array_buffer.is_object() || !is<ArrayBuffer>(array_buffer.as_object()))
+        return vm.throw_completion<TypeError>();
+
+    auto& array_buffer_object = static_cast<ArrayBuffer&>(array_buffer.as_object());
+    TRY(JS::detach_array_buffer(vm, array_buffer_object, vm.argument(1)));
+    return js_null();
+}
+
+JS_DEFINE_NATIVE_FUNCTION($262Object::eval_script)
+{
+    auto source_text = TRY(vm.argument(0).to_deprecated_string(vm));
+
+    // 1. Let hostDefined be any host-defined values for the provided sourceText (obtained in an implementation dependent manner)
+
+    // 2. Let realm be the current Realm Record.
+    auto& realm = *vm.current_realm();
+
+    // 3. Let s be ParseScript(sourceText, realm, hostDefined).
+    auto script_or_error = Script::parse(source_text, realm);
+
+    // 4. If s is a List of errors, then
+    if (script_or_error.is_error()) {
+        // a. Let error be the first element of s.
+        auto& error = script_or_error.error()[0];
+
+        // b. Return Completion { [[Type]]: throw, [[Value]]: error, [[Target]]: empty }.
+        return vm.throw_completion<SyntaxError>(TRY_OR_THROW_OOM(vm, error.to_string()));
+    }
+
+    // 5. Let status be ScriptEvaluation(s).
+    auto status = [&] {
+        if (auto* bytecode_interpreter = vm.bytecode_interpreter_if_exists())
+            return bytecode_interpreter->run(script_or_error.value());
+        else
+            return vm.interpreter().run(script_or_error.value());
+    }();
+
+    // 6. Return Completion(status).
+    return status;
+}
+
+}