Add details about Carbon 3 upgrade (#9653)

alexpgates · web-flow · commit b8bf6ca8a64b · 2024-05-13T12:08:43.000-05:00
Adds a bit more context about changes to Carbon 3's `diffIn*`changes.
diff --git a/upgrade.md b/upgrade.md
@@ -414,7 +414,7 @@ public function scalar($query, $bindings = [], $useReadPdo = true);
 
 **Likelihood Of Impact: Medium**
 
-Laravel 11 supports both Carbon 2 and Carbon 3. Carbon is a date manipulation library utilized extensively by Laravel and packages throughout the ecosystem. If you install Carbon 3, you should review Carbon's [change log](https://github.com/briannesbitt/Carbon/releases/tag/3.0.0).
+Laravel 11 supports both Carbon 2 and Carbon 3. Carbon is a date manipulation library utilized extensively by Laravel and packages throughout the ecosystem. If you upgrade to Carbon 3, be aware that `diffIn*` methods now return floating-point numbers and may return negative values to indicate time direction, which is a significant change from Carbon 2. Review Carbon's [change log](https://github.com/briannesbitt/Carbon/releases/tag/3.0.0) for detailed information on how to handle these and other changes.
 
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