From 8d9a30cc821c85b5310c4aa3f1b068dfb4eac2f5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?JC=20P=C3=A9rez=20Chavez?= <jcperezch@meta.com>
Date: Mon, 2 Nov 2026 11:45:39 -0800
Subject: [PATCH] Remove $FlowExpectedError[sketchy-null-string] (utils.js)
 (#59765)

Summary:

Replace `commandResult.stdout || '(empty)'` and `commandResult.stderr || '(empty)'` with explicit null-or-empty checks, and remove their `$FlowExpectedError[sketchy-null-string]` suppressions.

Both fields are `?string`. `x || '(empty)'` falls back only for `undefined`, `null` and `''`; `x == null || x === '' ? '(empty)' : x` falls back for exactly those values and keeps every other string, including whitespace. The header line, `stdout` and `stderr` are each read once, in the original order.

Changelog: [Internal]

Differential Revision: D128806028
---
 private/react-native-fantom/runner/utils.js | 12 +++++++-----
 1 file changed, 7 insertions(+), 5 deletions(-)

diff --git a/private/react-native-fantom/runner/utils.js b/private/react-native-fantom/runner/utils.js
index d7a75e8e0e5f..3c23536eff09 100644
--- a/private/react-native-fantom/runner/utils.js
+++ b/private/react-native-fantom/runner/utils.js
@@ -268,16 +268,18 @@ export function getDebugInfoFromCommandResult(
       ? 'succeeded'
       : `failed (status code: ${commandResult.status ?? '(empty)'}${maybeSignal})`;
 
+  const commandLine = `Command ${resultByStatus}: ${commandResult.originalCommand}`;
+  const stdout = commandResult.stdout;
+  const stderr = commandResult.stderr;
+
   const logLines = [
-    `Command ${resultByStatus}: ${commandResult.originalCommand}`,
+    commandLine,
     '',
     'stdout:',
-    // $FlowExpectedError[sketchy-null-string]
-    commandResult.stdout || '(empty)',
+    stdout == null || stdout === '' ? '(empty)' : stdout,
     '',
     'stderr:',
-    // $FlowExpectedError[sketchy-null-string]
-    commandResult.stderr || '(empty)',
+    stderr == null || stderr === '' ? '(empty)' : stderr,
   ];
 
   if (commandResult.error) {