LibJS: Implement Function.prototype.bind()

1 files changed, 66 insertions, 0 deletions

diff --git a/Libraries/LibJS/Runtime/BoundFunction.h b/Libraries/LibJS/Runtime/BoundFunction.h
new file mode 100644
index 0000000000..27387843df
--- /dev/null
+++ b/Libraries/LibJS/Runtime/BoundFunction.h
@@ -0,0 +1,66 @@
+/*
+ * Copyright (c) 2020, Jack Karamanian <karamanian.jack@gmail.com>
+ * 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/Function.h>
+
+namespace JS {
+
+class BoundFunction final : public Function {
+public:
+    BoundFunction(Function& target_function, Value bound_this, Vector<Value> arguments, i32 length, Object* constructor_prototype);
+
+    virtual ~BoundFunction();
+
+    virtual Value call(Interpreter& interpreter) override;
+
+    virtual Value construct(Interpreter& interpreter) override;
+
+    virtual LexicalEnvironment* create_environment() override;
+
+    virtual void visit_children(Visitor&) override;
+
+    virtual const FlyString& name() const override
+    {
+        return m_name;
+    }
+
+    Function& target_function() const
+    {
+        return *m_target_function;
+    }
+
+private:
+    virtual bool is_bound_function() const override { return true; }
+    virtual const char* class_name() const override { return "BoundFunction"; }
+
+    Function* m_target_function = nullptr;
+    Object* m_constructor_prototype = nullptr;
+    FlyString m_name;
+};
+
+}