From da7c6b93b57171c37646c51569eaac94562b8a1f Mon Sep 17 00:00:00 2001
From: Christoph Knittel <ck@cca.io>
Date: Thu, 11 Sep 2025 08:22:58 +0200
Subject: [PATCH 1/2] Float.isNaN: use Number.isNaN instead of isNaN

---
 packages/@rescript/runtime/Stdlib_Float.res        | 2 +-
 packages/@rescript/runtime/Stdlib_Float.resi       | 4 ++--
 packages/@rescript/runtime/lib/es6/Stdlib_Float.js | 2 +-
 packages/@rescript/runtime/lib/es6/Stdlib_Int.js   | 2 +-
 packages/@rescript/runtime/lib/js/Stdlib_Float.js  | 2 +-
 packages/@rescript/runtime/lib/js/Stdlib_Int.js    | 2 +-
 tests/tests/src/core/Core_FloatTests.mjs           | 2 +-
 7 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/packages/@rescript/runtime/Stdlib_Float.res b/packages/@rescript/runtime/Stdlib_Float.res
index e41be0b356..3e66e97caf 100644
--- a/packages/@rescript/runtime/Stdlib_Float.res
+++ b/packages/@rescript/runtime/Stdlib_Float.res
@@ -13,7 +13,7 @@ external equal: (float, float) => bool = "%equal"
 
 external compare: (float, float) => Stdlib_Ordering.t = "%compare"
 
-@val external isNaN: float => bool = "isNaN"
+@val @scope("Number") external isNaN: float => bool = "isNaN"
 @val external isFinite: float => bool = "isFinite"
 @val external parseFloat: 'a => float = "parseFloat"
 // parseInt's return type is a float because it can be NaN
diff --git a/packages/@rescript/runtime/Stdlib_Float.resi b/packages/@rescript/runtime/Stdlib_Float.resi
index ef67cfda09..f0f2b78a5b 100644
--- a/packages/@rescript/runtime/Stdlib_Float.resi
+++ b/packages/@rescript/runtime/Stdlib_Float.resi
@@ -139,7 +139,7 @@ external compare: (float, float) => Stdlib_Ordering.t = "%compare"
 
 /**
 `isNaN(v)` tests if the given `v` is `NaN`.
-See [`NaN`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/NaN) on MDN.
+See [`isNaN`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Number/isNaN) on MDN.
 
 ## Examples
 
@@ -148,7 +148,7 @@ Float.isNaN(3.0) // false
 Float.isNaN(Float.Constants.nan) // true
 ```
 */
-@val
+@val @scope("Number")
 external isNaN: float => bool = "isNaN"
 
 /**
diff --git a/packages/@rescript/runtime/lib/es6/Stdlib_Float.js b/packages/@rescript/runtime/lib/es6/Stdlib_Float.js
index d0955e3ce0..7cb1e62d88 100644
--- a/packages/@rescript/runtime/lib/es6/Stdlib_Float.js
+++ b/packages/@rescript/runtime/lib/es6/Stdlib_Float.js
@@ -5,7 +5,7 @@ let Constants = {};
 
 function fromString(i) {
   let i$1 = parseFloat(i);
-  if (isNaN(i$1)) {
+  if (Number.isNaN(i$1)) {
     return;
   } else {
     return i$1;
diff --git a/packages/@rescript/runtime/lib/es6/Stdlib_Int.js b/packages/@rescript/runtime/lib/es6/Stdlib_Int.js
index 4993a6297c..9f2ba3a6d1 100644
--- a/packages/@rescript/runtime/lib/es6/Stdlib_Int.js
+++ b/packages/@rescript/runtime/lib/es6/Stdlib_Int.js
@@ -4,7 +4,7 @@ import * as Stdlib_Array from "./Stdlib_Array.js";
 
 function fromString(x, radix) {
   let maybeInt = radix !== undefined ? parseInt(x, radix) : parseInt(x);
-  if (isNaN(maybeInt) || maybeInt > 2147483647 || maybeInt < -2147483648) {
+  if (Number.isNaN(maybeInt) || maybeInt > 2147483647 || maybeInt < -2147483648) {
     return;
   } else {
     return maybeInt | 0;
diff --git a/packages/@rescript/runtime/lib/js/Stdlib_Float.js b/packages/@rescript/runtime/lib/js/Stdlib_Float.js
index ecb91a0c04..c34f9395a3 100644
--- a/packages/@rescript/runtime/lib/js/Stdlib_Float.js
+++ b/packages/@rescript/runtime/lib/js/Stdlib_Float.js
@@ -5,7 +5,7 @@ let Constants = {};
 
 function fromString(i) {
   let i$1 = parseFloat(i);
-  if (isNaN(i$1)) {
+  if (Number.isNaN(i$1)) {
     return;
   } else {
     return i$1;
diff --git a/packages/@rescript/runtime/lib/js/Stdlib_Int.js b/packages/@rescript/runtime/lib/js/Stdlib_Int.js
index 5e6dbb7ced..dbd70277e6 100644
--- a/packages/@rescript/runtime/lib/js/Stdlib_Int.js
+++ b/packages/@rescript/runtime/lib/js/Stdlib_Int.js
@@ -4,7 +4,7 @@ let Stdlib_Array = require("./Stdlib_Array.js");
 
 function fromString(x, radix) {
   let maybeInt = radix !== undefined ? parseInt(x, radix) : parseInt(x);
-  if (isNaN(maybeInt) || maybeInt > 2147483647 || maybeInt < -2147483648) {
+  if (Number.isNaN(maybeInt) || maybeInt > 2147483647 || maybeInt < -2147483648) {
     return;
   } else {
     return maybeInt | 0;
diff --git a/tests/tests/src/core/Core_FloatTests.mjs b/tests/tests/src/core/Core_FloatTests.mjs
index 865bbe9cba..2a08805ebb 100644
--- a/tests/tests/src/core/Core_FloatTests.mjs
+++ b/tests/tests/src/core/Core_FloatTests.mjs
@@ -105,7 +105,7 @@ Test.run([
     33
   ],
   "clamp - nan"
-], isNaN(Stdlib_Float.clamp(4.1, 4.3, Number.NaN)), eq, true);
+], Number.isNaN(Stdlib_Float.clamp(4.1, 4.3, Number.NaN)), eq, true);
 
 Test.run([
   [

From fa87b4b09dff74701a0bdd160a3e7325c40f4a63 Mon Sep 17 00:00:00 2001
From: Christoph Knittel <ck@cca.io>
Date: Thu, 11 Sep 2025 14:28:01 +0200
Subject: [PATCH 2/2] CHANGELOG

---
 CHANGELOG.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index 0a69f1052b..031cc623b6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -32,6 +32,7 @@
 #### :nail_care: Polish
 
 - Reactivate optimization for length of array literals. https://github.com/rescript-lang/rescript/pull/7872
+- `Float.isNaN`: use `Number.isNaN` instead of global `isNaN`. https://github.com/rescript-lang/rescript/pull/7874
 
 #### :house: Internal