From 8b1867422939d8f5ee66aafdd8684b7f0f0f492d Mon Sep 17 00:00:00 2001
From: Andreas Kling <kling@serenityos.org>
Date: Sat, 21 Mar 2020 17:52:12 +0100
Subject: [PATCH] LibJS: Add Math.random() :^)

---
 Libraries/LibJS/Makefile                 |  1 +
 Libraries/LibJS/Runtime/GlobalObject.cpp |  2 ++
 Libraries/LibJS/Runtime/MathObject.cpp   | 44 ++++++++++++++++++++++++
 Libraries/LibJS/Runtime/MathObject.h     | 42 ++++++++++++++++++++++
 4 files changed, 89 insertions(+)
 create mode 100644 Libraries/LibJS/Runtime/MathObject.cpp
 create mode 100644 Libraries/LibJS/Runtime/MathObject.h

diff --git a/Libraries/LibJS/Makefile b/Libraries/LibJS/Makefile
index cb1f5141ed..e550349a57 100644
--- a/Libraries/LibJS/Makefile
+++ b/Libraries/LibJS/Makefile
@@ -12,6 +12,7 @@ OBJS = \
     Runtime/ConsoleObject.o \
     Runtime/Function.o \
     Runtime/GlobalObject.o \
+    Runtime/MathObject.o \
     Runtime/NativeFunction.o \
     Runtime/NativeProperty.o \
     Runtime/Object.o \
diff --git a/Libraries/LibJS/Runtime/GlobalObject.cpp b/Libraries/LibJS/Runtime/GlobalObject.cpp
index c8459d7105..770ccddd65 100644
--- a/Libraries/LibJS/Runtime/GlobalObject.cpp
+++ b/Libraries/LibJS/Runtime/GlobalObject.cpp
@@ -4,6 +4,7 @@
 #include <LibJS/Interpreter.h>
 #include <LibJS/Runtime/ConsoleObject.h>
 #include <LibJS/Runtime/GlobalObject.h>
+#include <LibJS/Runtime/MathObject.h>
 #include <LibJS/Runtime/NativeFunction.h>
 #include <LibJS/Runtime/Value.h>
 
@@ -17,6 +18,7 @@ GlobalObject::GlobalObject()
         this_object->heap().collect_garbage();
         return js_undefined();
     });
+    put("Math", heap().allocate<MathObject>());
 }
 
 GlobalObject::~GlobalObject()
diff --git a/Libraries/LibJS/Runtime/MathObject.cpp b/Libraries/LibJS/Runtime/MathObject.cpp
new file mode 100644
index 0000000000..23ef4d6bda
--- /dev/null
+++ b/Libraries/LibJS/Runtime/MathObject.cpp
@@ -0,0 +1,44 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <AK/Function.h>
+#include <LibJS/Runtime/MathObject.h>
+
+namespace JS {
+
+MathObject::MathObject()
+{
+    put_native_function("random", [](Object*, const Vector<Value>&) {
+        double r = (double)arc4random() / (double)UINT32_MAX;
+        return Value(r);
+    });
+}
+
+MathObject::~MathObject()
+{
+}
+
+}
diff --git a/Libraries/LibJS/Runtime/MathObject.h b/Libraries/LibJS/Runtime/MathObject.h
new file mode 100644
index 0000000000..a52aadc68d
--- /dev/null
+++ b/Libraries/LibJS/Runtime/MathObject.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice, this
+ *    list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#pragma once
+
+#include <LibJS/Runtime/Object.h>
+
+namespace JS {
+
+class MathObject final : public Object {
+public:
+    MathObject();
+    virtual ~MathObject() override;
+
+private:
+    virtual const char* class_name() const override { return "MathObject"; }
+};
+
+}