From 342bae08c9ee4d03eed2e0ef4d54d3d251d06c62 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Sat, 15 Feb 2025 11:06:13 -0500
Subject: [PATCH 1/2] Editorial: Split TypedArray [[DefineOwnProperty]] into
 distinct branches by mutability

---
 spec.emu | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/spec.emu b/spec.emu
index c3d88b7..60dbea3 100644
--- a/spec.emu
+++ b/spec.emu
@@ -99,18 +99,21 @@ contributors: Mark S. Miller, Richard Gibson
             1. Let _numericIndex_ be CanonicalNumericIndexString(_P_).
             1. If _numericIndex_ is not *undefined*, then
               1. If IsValidIntegerIndex(_O_, _numericIndex_) is *false*, return *false*.
-              1. <ins>Let _mutable_ be *true*.</ins>
-              1. <ins>If IsImmutableBuffer(_O_.[[ViewedArrayBuffer]]) is *true*, set _mutable_ to *false*.</ins>
-              1. If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is <del>*false*</del> <ins>not _mutable_</ins>, return *false*.
-              1. If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.
-              1. If IsAccessorDescriptor(_Desc_) is *true*, return *false*.
-              1. If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is <del>*false*</del> <ins>not _mutable_</ins>, return *false*.
-              1. <del>If _Desc_ has a [[Value]] field, perform ? TypedArraySetElement(_O_, _numericIndex_, _Desc_.[[Value]]).</del>
-              1. <ins>If _Desc_ has a [[Value]] field, then</ins>
+              1. <ins>If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.</ins>
+              1. <ins>If IsAccessorDescriptor(_Desc_) is *true*, return *false*.</ins>
+              1. <ins>If IsImmutableBuffer(_O_.[[ViewedArrayBuffer]]) is *false*, then</ins>
+                1. If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is *false*, return *false*.
+                1. <del>If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.</del>
+                1. <del>If IsAccessorDescriptor(_Desc_) is *true*, return *false*.</del>
+                1. If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is *false*, return *false*.
+                1. If _Desc_ has a [[Value]] field, perform ? TypedArraySetElement(_O_, _numericIndex_, _Desc_.[[Value]]).
+                1. Return *true*.
+              1. <ins>Else,</ins>
+                1. <ins>If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is *true*, return *false*.</ins>
+                1. <ins>If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is *true*, return *false*.</ins>
                 1. <ins>NOTE: Attempting to redefine an immutable value always fails, even if the new value would be cast to the current value.</ins>
-                1. <ins>If _mutable_ is *false* and SameValue(_Desc_.[[Value]], TypedArrayGetElement(_O_, _numericIndex_)) is *false*, return *false*.</ins>
-                1. <ins>If _mutable_ is *true*, perform ? TypedArraySetElement(_O_, _numericIndex_, _Desc_.[[Value]]).</ins>
-              1. Return *true*.
+                1. <ins>If _Desc_ has a [[Value]] field and SameValue(_Desc_.[[Value]], TypedArrayGetElement(_O_, _numericIndex_)) is *false*, return *false*.</ins>
+                1. <ins>Return *true*.</ins>
           1. Return ! OrdinaryDefineOwnProperty(_O_, _P_, _Desc_).
         </emu-alg>
       </emu-clause>

From e2315160233514d7c68c17cf32cf8a83df2e2867 Mon Sep 17 00:00:00 2001
From: Richard Gibson <richard.gibson@gmail.com>
Date: Sat, 15 Feb 2025 11:06:13 -0500
Subject: [PATCH 2/2] Editorial: Defer the TypedArray [[DefineOwnProperty]]
 immutable branch to ValidateAndApplyPropertyDescriptor

---
 spec.emu | 24 ++++++++++--------------
 1 file changed, 10 insertions(+), 14 deletions(-)

diff --git a/spec.emu b/spec.emu
index 60dbea3..475cd19 100644
--- a/spec.emu
+++ b/spec.emu
@@ -99,21 +99,17 @@ contributors: Mark S. Miller, Richard Gibson
             1. Let _numericIndex_ be CanonicalNumericIndexString(_P_).
             1. If _numericIndex_ is not *undefined*, then
               1. If IsValidIntegerIndex(_O_, _numericIndex_) is *false*, return *false*.
-              1. <ins>If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.</ins>
-              1. <ins>If IsAccessorDescriptor(_Desc_) is *true*, return *false*.</ins>
-              1. <ins>If IsImmutableBuffer(_O_.[[ViewedArrayBuffer]]) is *false*, then</ins>
-                1. If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is *false*, return *false*.
-                1. <del>If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.</del>
-                1. <del>If IsAccessorDescriptor(_Desc_) is *true*, return *false*.</del>
-                1. If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is *false*, return *false*.
-                1. If _Desc_ has a [[Value]] field, perform ? TypedArraySetElement(_O_, _numericIndex_, _Desc_.[[Value]]).
-                1. Return *true*.
-              1. <ins>Else,</ins>
-                1. <ins>If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is *true*, return *false*.</ins>
-                1. <ins>If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is *true*, return *false*.</ins>
+              1. <ins>If IsImmutableBuffer(_O_.[[ViewedArrayBuffer]]) is *true*, then</ins>
+                1. <ins>Let _current_ be ! <emu-meta suppress-effects="user-code">_O_.[[GetOwnProperty]](_P_)</emu-meta>.</ins>
+                1. <ins>Assert: _current_.[[Configurable]] and _current_.[[Writable]] are both *false*.</ins>
                 1. <ins>NOTE: Attempting to redefine an immutable value always fails, even if the new value would be cast to the current value.</ins>
-                1. <ins>If _Desc_ has a [[Value]] field and SameValue(_Desc_.[[Value]], TypedArrayGetElement(_O_, _numericIndex_)) is *false*, return *false*.</ins>
-                1. <ins>Return *true*.</ins>
+                1. <ins>Return ValidateAndApplyPropertyDescriptor(_O_, _P_, *false*, _Desc_, _current_).</ins>
+              1. If _Desc_ has a [[Configurable]] field and _Desc_.[[Configurable]] is *false*, return *false*.
+              1. If _Desc_ has an [[Enumerable]] field and _Desc_.[[Enumerable]] is *false*, return *false*.
+              1. If IsAccessorDescriptor(_Desc_) is *true*, return *false*.
+              1. If _Desc_ has a [[Writable]] field and _Desc_.[[Writable]] is *false*, return *false*.
+              1. If _Desc_ has a [[Value]] field, perform ? TypedArraySetElement(_O_, _numericIndex_, _Desc_.[[Value]]).
+              1. Return *true*.
           1. Return ! OrdinaryDefineOwnProperty(_O_, _P_, _Desc_).
         </emu-alg>
       </emu-clause>