From bded3cec2e69ed30f9341a693a2b3dd67eaa8ccc Mon Sep 17 00:00:00 2001
From: Carl Bergman <30546+carlbergman@users.noreply.github.com>
Date: Thu, 5 Mar 2026 15:52:29 +0100
Subject: [PATCH 1/2] [compiler] Add fixture for custom hook with use() not
 compiled

Custom hooks whose only invocation is the `use()` function are
skipped by the compiler. This fixture demonstrates the
current (broken) output where `useMyContext` is not compiled.

Ref #35960
---
 .../compiler/use-operator-in-hook.expect.md   | 43 +++++++++++++++++++
 .../fixtures/compiler/use-operator-in-hook.js | 14 ++++++
 2 files changed, 57 insertions(+)
 create mode 100644 compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
 create mode 100644 compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js

diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
new file mode 100644
index 000000000000..cdd5651cfade
--- /dev/null
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
@@ -0,0 +1,43 @@
+
+## Input
+
+```javascript
+// @compilationMode:"infer" @expectNothingCompiled
+import {use} from 'react';
+
+const MyContext = React.createContext(null);
+
+function useMyContext() {
+  const context = use(MyContext);
+  return [context];
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: useMyContext,
+  params: [],
+};
+
+```
+
+## Code
+
+```javascript
+// @compilationMode:"infer" @expectNothingCompiled
+import { use } from "react";
+
+const MyContext = React.createContext(null);
+
+function useMyContext() {
+  const context = use(MyContext);
+  return [context];
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: useMyContext,
+  params: [],
+};
+
+```
+      
+### Eval output
+(kind: ok) [null]
\ No newline at end of file
diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js
new file mode 100644
index 000000000000..2874390928bd
--- /dev/null
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js
@@ -0,0 +1,14 @@
+// @compilationMode:"infer" @expectNothingCompiled
+import {use} from 'react';
+
+const MyContext = React.createContext(null);
+
+function useMyContext() {
+  const context = use(MyContext);
+  return [context];
+}
+
+export const FIXTURE_ENTRYPOINT = {
+  fn: useMyContext,
+  params: [],
+};

From 2d02a52f29097736b8c4f0d771a5eecce85afd6e Mon Sep 17 00:00:00 2001
From: Carl Bergman <30546+carlbergman@users.noreply.github.com>
Date: Thu, 5 Mar 2026 17:00:04 +0100
Subject: [PATCH 2/2] [compiler] Fix detection of use() in custom hooks for
 infer mode

The `isHookName` check in Program.ts used the regex `/^use[A-Z0-9]/`
which doesn't match `use()`. This caused custom hooks whose only
invocation is `use()` to be skipped in infer mode.

Fixes #35960
---
 .../src/Entrypoint/Program.ts                     |  2 +-
 .../compiler/use-operator-in-hook.expect.md       | 15 ++++++++++++---
 .../fixtures/compiler/use-operator-in-hook.js     |  2 +-
 3 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
index 2880e9283c77..75b54a7dc7ec 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
+++ b/compiler/packages/babel-plugin-react-compiler/src/Entrypoint/Program.ts
@@ -895,7 +895,7 @@ function hasMemoCacheFunctionImport(
 }
 
 function isHookName(s: string): boolean {
-  return /^use[A-Z0-9]/.test(s);
+  return /^use[A-Z0-9]/.test(s) || s === 'use';
 }
 
 /*
diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
index cdd5651cfade..a22fc4e54100 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.expect.md
@@ -2,7 +2,7 @@
 ## Input
 
 ```javascript
-// @compilationMode:"infer" @expectNothingCompiled
+// @compilationMode:"infer"
 import {use} from 'react';
 
 const MyContext = React.createContext(null);
@@ -22,14 +22,23 @@ export const FIXTURE_ENTRYPOINT = {
 ## Code
 
 ```javascript
-// @compilationMode:"infer" @expectNothingCompiled
+import { c as _c } from "react/compiler-runtime"; // @compilationMode:"infer"
 import { use } from "react";
 
 const MyContext = React.createContext(null);
 
 function useMyContext() {
+  const $ = _c(2);
   const context = use(MyContext);
-  return [context];
+  let t0;
+  if ($[0] !== context) {
+    t0 = [context];
+    $[0] = context;
+    $[1] = t0;
+  } else {
+    t0 = $[1];
+  }
+  return t0;
 }
 
 export const FIXTURE_ENTRYPOINT = {
diff --git a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js
index 2874390928bd..dfa92b78bf08 100644
--- a/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js
+++ b/compiler/packages/babel-plugin-react-compiler/src/__tests__/fixtures/compiler/use-operator-in-hook.js
@@ -1,4 +1,4 @@
-// @compilationMode:"infer" @expectNothingCompiled
+// @compilationMode:"infer"
 import {use} from 'react';
 
 const MyContext = React.createContext(null);