From 6e8e0d98fa4849a72db712b96899fdbf77f84932 Mon Sep 17 00:00:00 2001
From: Iban Eguia Moraza <razican@protonmail.ch>
Date: Fri, 22 May 2020 22:28:23 +0200
Subject: [PATCH] Adding native error types, starting with `RangeError`

---
 boa/src/builtins/{error.rs => error/mod.rs} |  9 ++-
 boa/src/builtins/error/range.rs             | 67 +++++++++++++++++++++
 boa/src/builtins/number/mod.rs              |  2 +-
 boa/src/exec/mod.rs                         | 13 ++--
 4 files changed, 82 insertions(+), 9 deletions(-)
 rename boa/src/builtins/{error.rs => error/mod.rs} (94%)
 create mode 100644 boa/src/builtins/error/range.rs

diff --git a/boa/src/builtins/error.rs b/boa/src/builtins/error/mod.rs
similarity index 94%
rename from boa/src/builtins/error.rs
rename to boa/src/builtins/error/mod.rs
index 35f4e91c44c..2293ea5ba2a 100644
--- a/boa/src/builtins/error.rs
+++ b/boa/src/builtins/error/mod.rs
@@ -10,15 +10,22 @@
 //! [spec]: https://tc39.es/ecma262/#sec-error-objects
 //! [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error
 
-use super::function::make_constructor_fn;
 use crate::{
     builtins::{
+        function::make_constructor_fn,
         object::ObjectKind,
         value::{ResultValue, Value},
     },
     exec::Interpreter,
 };
 
+// mod eval;
+pub mod range;
+// mod reference;
+// mod syntax;
+// mod type_err;
+// mod uri;
+
 /// Create a new error object.
 pub fn make_error(this: &mut Value, args: &[Value], _: &mut Interpreter) -> ResultValue {
     if !args.is_empty() {
diff --git a/boa/src/builtins/error/range.rs b/boa/src/builtins/error/range.rs
new file mode 100644
index 00000000000..72492728322
--- /dev/null
+++ b/boa/src/builtins/error/range.rs
@@ -0,0 +1,67 @@
+//! This module implements the global `RangeError` object.
+//!
+//! Indicates a value that is not in the set or range of allowable values.
+//!
+//! More information:
+//!  - [MDN documentation][mdn]
+//!  - [ECMAScript reference][spec]
+//!
+//! [spec]: https://tc39.es/ecma262/#sec-native-error-types-used-in-this-standard-rangeerror
+//! [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RangeError
+
+use crate::{
+    builtins::{
+        function::make_constructor_fn,
+        object::ObjectKind,
+        value::{ResultValue, Value},
+    },
+    exec::Interpreter,
+};
+
+/// Create a new error object.
+pub fn make_error(this: &mut Value, args: &[Value], _: &mut Interpreter) -> ResultValue {
+    if !args.is_empty() {
+        this.set_field_slice(
+            "message",
+            Value::from(
+                args.get(0)
+                    .expect("failed getting error message")
+                    .to_string(),
+            ),
+        );
+    }
+    // This value is used by console.log and other routines to match Object type
+    // to its Javascript Identifier (global constructor method name)
+    this.set_kind(ObjectKind::Error);
+    Ok(Value::undefined())
+}
+
+/// `Error.prototype.toString()`
+///
+/// The toString() method returns a string representing the specified Error object.
+///
+/// More information:
+///  - [MDN documentation][mdn]
+///  - [ECMAScript reference][spec]
+///
+/// [spec]: https://tc39.es/ecma262/#sec-error.prototype.tostring
+/// [mdn]: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Error/toString
+pub fn to_string(this: &mut Value, _: &[Value], _: &mut Interpreter) -> ResultValue {
+    let name = this.get_field_slice("name");
+    let message = this.get_field_slice("message");
+    Ok(Value::from(format!("{}: {}", name, message)))
+}
+
+/// Create a new `RangeError` object.
+pub fn create(global: &Value) -> Value {
+    let prototype = Value::new_object(Some(global));
+    prototype.set_field_slice("message", Value::from(""));
+    prototype.set_field_slice("name", Value::from("RangeError"));
+    make_builtin_fn!(to_string, named "toString", of prototype);
+    make_constructor_fn(make_error, global, prototype)
+}
+
+/// Initialise the global object with the `RangeError` object.
+pub fn init(global: &Value) {
+    global.set_field_slice("RangeError", create(global));
+}
diff --git a/boa/src/builtins/number/mod.rs b/boa/src/builtins/number/mod.rs
index 0da8860f5ac..d1692f001f2 100644
--- a/boa/src/builtins/number/mod.rs
+++ b/boa/src/builtins/number/mod.rs
@@ -318,7 +318,7 @@ pub fn to_string(this: &mut Value, args: &[Value], _ctx: &mut Interpreter) -> Re
 
     // 4. If radixNumber < 2 or radixNumber > 36, throw a RangeError exception.
     if radix_number < 2 || radix_number > 36 {
-        panic!("Radix must be between 2 and 36");
+        panic!("RangeError: radix must be an integer at least 2 and no greater than 36");
     }
 
     // 5. If radixNumber = 10, return ! ToString(x).
diff --git a/boa/src/exec/mod.rs b/boa/src/exec/mod.rs
index 8e7524341cb..5ea5b5d4044 100644
--- a/boa/src/exec/mod.rs
+++ b/boa/src/exec/mod.rs
@@ -109,13 +109,12 @@ impl Interpreter {
         this: &mut Value,
         arguments_list: &[Value],
     ) -> ResultValue {
-        // All functions should be objects, and eventually will be.
-        // During this transition call will support both native functions and function objects
-        match (*f).deref() {
-            ValueData::Object(ref obj) => match (*obj).deref().borrow().func {
-                Some(ref func) => func.call(&mut f.clone(), arguments_list, self, this),
-                None => panic!("Expected function"),
-            },
+        match *f.data() {
+            ValueData::Object(ref obj) => {
+                let obj = (**obj).borrow();
+                let func = obj.func.as_ref().expect("Expected function");
+                func.call(&mut f.clone(), arguments_list, self, this)
+            }
             _ => Err(Value::undefined()),
         }
     }