From 077eda6fb34d1acb9c758838a404a28e5cf33974 Mon Sep 17 00:00:00 2001
From: "Alex A. Naanou" <alex.nanou@gmail.com>
Date: Wed, 7 Dec 2022 15:47:24 +0300
Subject: [PATCH] added ASIS(..) wrapper to help prevent values returned by
 .__new__(..) from being intergrated into the current object prototype chain
 enabling constructors to return non-instance values.

Signed-off-by: Alex A. Naanou <alex.nanou@gmail.com>
---
 README.md    | 13 +++++++++++++
 object.js    | 20 ++++++++++++++++++--
 package.json |  2 +-
 test.js      | 30 +++++++++++++++++++++++++++++-
 4 files changed, 61 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 12db264..a45f97d 100755
--- a/README.md
+++ b/README.md
@@ -130,6 +130,7 @@ class B extends A {
     - [`<object>.__call__(..)`](#object__call__)
   - [Components](#components)
     - [`STOP` / `STOP(..)`](#stop--stop)
+    - [`ASIS(..)`](#asis)
     - [`Constructor(..)` / `C(..)`](#constructor--c)
     - [`create(..)` / `Constructor.create(..)`](#create--constructorcreate)
     - [`sources(..)` / `Constructor.sources(..)`](#sources--constructorsources)
@@ -508,6 +509,13 @@ no instance exists yet.
 `<context>` is the _outer_ context of the call, i.e. the object from which 
 `<constructor>` was referenced before it was called.
 
+Any value returned by `.__new__(..)` will be integrated into the prototype 
+chain of `<object>`, if this is not desired then wrap it in 
+[`object.ASIS(..)`](#asis) before returning, but note that this will 
+not prevent `<object>.__init__(..)` from being called. The `ASIS(..)`-wrapped 
+value will be unwrapped before being returned by the constructor.
+
+
 For more info see: 
 - [Low level constructor](#low-level-constructor), 
 - [Inheriting from native constructor objects](#inheriting-from-native-constructor-objects)
@@ -564,6 +572,11 @@ to stop the search before it reaches the top of
 the prototype chain.
 
 
+### `ASIS(..)`
+
+Can be used in [`.__new__(..)`](#object__new__) to wrap the returned object to 
+prevent changing it's prototype by [`RawInstance()`](#rawinstance).
+
 
 ### `Constructor(..)` / `C(..)`
 
diff --git a/object.js b/object.js
index d26a8a7..d25f69c 100755
--- a/object.js
+++ b/object.js
@@ -241,6 +241,15 @@ function(obj){
 //---------------------------------------------------------------------
 // Helper objects/constructors...
 
+var ASIS =
+module.ASIS = 
+function ASIS(value){
+	return {
+		__proto__: ASIS.prototype,
+		value, 
+	} }
+
+
 BOOTSTRAP(function(){
 
 	// Error with some JS quirks fixed...
@@ -647,6 +656,10 @@ function(context, constructor, ...args){
 		// default object base...
 		: Reflect.construct(Object, [], constructor)
 
+	// return wrapped object as-is...
+	if(obj instanceof module.ASIS){
+		return obj.value }
+
 	// link to prototype chain, if not done already...
 	obj.__proto__ !== constructor.prototype
 		&& (obj.__proto__ = constructor.prototype)
@@ -917,8 +930,11 @@ function Constructor(name, a, b, c){
 			_constructor.__rawinstance__(this, ...arguments)
 			: RawInstance(this, _constructor, ...arguments)
 		// initialize...
-		obj.__init__ instanceof Function
-			&& obj.__init__(...arguments)
+		// NOTE: we are using _constructor.prototype.__init__ here instead 
+		// 		of obj.__init__ as at this point object may be of a different 
+		// 		type (see RawInstance + ASIS)...
+		_constructor.prototype.__init__ instanceof Function
+			&& _constructor.prototype.__init__.call(obj, ...arguments)
 		return obj }
 	// rename the consructor...
 	// NOTE: we are not using:
diff --git a/package.json b/package.json
index eaef069..3d28562 100755
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "ig-object",
-  "version": "6.2.0",
+  "version": "6.2.1",
   "description": "",
   "main": "object.js",
   "scripts": {
diff --git a/test.js b/test.js
index 6251833..9a1c844 100755
--- a/test.js
+++ b/test.js
@@ -205,7 +205,7 @@ var setups = test.Setups({
 
 	// initialization...
 	init: function(assert){
-		var A, B, C
+		var A, B, C, D
 		return {
 			// init...
 			A: A = assert(object.C('A', {
@@ -225,6 +225,7 @@ var setups = test.Setups({
 					return o
 				},
 				test_new: function(){
+					assert(this instanceof B, 'instanceof correct') 
 					assert(this.new_has_run, '.__new__() run') },
 			}), 'basic .__new__(..)'),
 			// new + init...
@@ -622,6 +623,33 @@ var tests = test.Tests({
 
 
 var cases = test.Cases({
+	'as-is-new': function(assert){
+		var A = object.C('A', {
+			__init__: function(){
+				this.init_A_did_run = true },
+		})
+		var B = object.C('B', {
+			__new__: function(){
+				return object.ASIS(A()) },
+		})
+
+		var b = B()
+
+		assert(b instanceof A, 'not instance of A')
+		assert(!(b instanceof B), 'not instance of B')
+
+		var C = object.C('C', {
+			__new__: function(){
+				return object.ASIS(A()) },
+			__init__: function(){
+				this.init_C_did_run = true },
+		})
+
+		var c = C()
+
+		assert(c.init_A_did_run, 'base .__init__() ran')
+		assert(c.init_C_did_run, 'constructor .__init__() ran')
+	},
 	'edge-cases': function(assert){
 		// bad names...
 		assert.error('Constructor(..): malformed name',