From 9710853baf9649fed556dc0e9d39765649675b7b Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Sebastian=20Markb=C3=A5ge?= <sebastian@calyptus.eu>
Date: Thu, 30 May 2024 15:00:55 -0400
Subject: [PATCH] [Flight] Try/Catch Eval (#29671)

Follow up to https://github.com/facebook/react/pull/29632.

It's possible for `eval` to throw such as if we're in a CSP environment.
This is non-essential debug information. We can still proceed to create
a fake stack entry. It'll still have the right name. It just won't have
the right line/col number nor source url/source map. It might also be
ignored listed since it's inside Flight.
---
 packages/react-client/src/ReactFlightClient.js | 16 +++++++++++++---
 1 file changed, 13 insertions(+), 3 deletions(-)

diff --git a/packages/react-client/src/ReactFlightClient.js b/packages/react-client/src/ReactFlightClient.js
index 7795b3025215d..3cd07de4b1f14 100644
--- a/packages/react-client/src/ReactFlightClient.js
+++ b/packages/react-client/src/ReactFlightClient.js
@@ -1648,7 +1648,7 @@ const taskCache: null | WeakMap<
   ConsoleTask,
 > = supportsCreateTask ? new WeakMap() : null;
 
-type FakeFunction<T> = (FakeFunction<T>) => T;
+type FakeFunction<T> = (() => T) => T;
 const fakeFunctionCache: Map<string, FakeFunction<any>> = __DEV__
   ? new Map()
   : (null: any);
@@ -1684,8 +1684,18 @@ function createFakeFunction<T>(
     code += '//# sourceURL=' + filename;
   }
 
-  // eslint-disable-next-line no-eval
-  const fn: FakeFunction<T> = (0, eval)(code);
+  let fn: FakeFunction<T>;
+  try {
+    // eslint-disable-next-line no-eval
+    fn = (0, eval)(code);
+  } catch (x) {
+    // If eval fails, such as if in an environment that doesn't support it,
+    // we fallback to creating a function here. It'll still have the right
+    // name but it'll lose line/column number and file name.
+    fn = function (_) {
+      return _();
+    };
+  }
   // $FlowFixMe[cannot-write]
   Object.defineProperty(fn, 'name', {value: name || '(anonymous)'});
   // $FlowFixMe[prop-missing]