Fix Object.defineProperty() (#1005)

- Fix panic if first argument is not supplied.
 - Fix panic if second argument is not supplied.
 - Fix bug when the object is not a object.
 - Implemented `DefinePropertyOrThrow()`

boa/src/builtins/object/mod.rs

@@ -287,19 +287,23 @@ impl Object {
 
     /// Define a property in an object
     pub fn define_property(_: &Value, args: &[Value], context: &mut Context) -> Result<Value> {
-        let obj = args.get(0).expect("Cannot get object");
-        let prop = args
-            .get(1)
-            .expect("Cannot get object")
-            .to_property_key(context)?;
-
-        let desc = if let Value::Object(ref object) = args.get(2).cloned().unwrap_or_default() {
-            object.to_property_descriptor(context)?
+        let object = args.get(0).cloned().unwrap_or_else(Value::undefined);
+        if let Some(mut object) = object.as_object() {
+            let key = args
+                .get(1)
+                .unwrap_or(&Value::undefined())
+                .to_property_key(context)?;
+            let desc = args
+                .get(2)
+                .unwrap_or(&Value::undefined())
+                .to_property_descriptor(context)?;
+
+            object.define_property_or_throw(key, desc, context)?;
+
+            Ok(object.into())
         } else {
-            return context.throw_type_error("Property description must be an object");
-        };
-        obj.set_property(prop, desc);
-        Ok(obj.clone())
+            context.throw_type_error("Object.defineProperty called on non-object")
+        }
     }
 
     /// `Object.defineProperties( proto, [propertiesObject] )`

boa/src/object/gcobject.rs

@@ -761,7 +761,6 @@ impl GcObject {
             Ok(false)
         }
     }
-
     #[inline]
     #[track_caller]
     pub fn has_own_property<K>(&self, key: K) -> bool
@@ -771,6 +770,34 @@ impl GcObject {
         let key = key.into();
         self.get_own_property(&key).is_some()
     }
+
+    /// Defines the property or throws a `TypeError` if the operation fails.
+    ///
+    /// More information:
+    /// - [EcmaScript reference][spec]
+    ///
+    /// [spec]: https://tc39.es/ecma262/#sec-definepropertyorthrow
+    #[inline]
+    pub(crate) fn define_property_or_throw<K, P>(
+        &mut self,
+        key: K,
+        desc: P,
+        context: &mut Context,
+    ) -> Result<()>
+    where
+        K: Into<PropertyKey>,
+        P: Into<PropertyDescriptor>,
+    {
+        let key = key.into();
+        let desc = desc.into();
+
+        let success = self.define_own_property(key.clone(), desc);
+        if !success {
+            Err(context.construct_type_error(format!("Cannot redefine property: {}", key)))
+        } else {
+            Ok(())
+        }
+    }
 }
 
 impl AsRef<GcCell<Object>> for GcObject {