From 355cf162b1d959e2625330045d1dd230740792a3 Mon Sep 17 00:00:00 2001
From: Maxwell Katz <maxkatz6@outlook.com>
Date: Fri, 14 Feb 2025 17:12:19 -0800
Subject: [PATCH] Add FontSize property validation (#18198)

* Add FontSize property validation

* Also disallow 0 value for the font size

* Also check for IsInfinity
---
 src/Avalonia.Controls/Documents/TextElement.cs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/Avalonia.Controls/Documents/TextElement.cs b/src/Avalonia.Controls/Documents/TextElement.cs
index e4e5fb8983..1d02161689 100644
--- a/src/Avalonia.Controls/Documents/TextElement.cs
+++ b/src/Avalonia.Controls/Documents/TextElement.cs
@@ -38,7 +38,8 @@ namespace Avalonia.Controls.Documents
             AvaloniaProperty.RegisterAttached<TextElement, TextElement, double>(
                 nameof(FontSize),
                 defaultValue: 12,
-                inherits: true);
+                inherits: true,
+                validate: fontSize => fontSize > 0 && !double.IsNaN(fontSize) && !double.IsInfinity(fontSize));
 
         /// <summary>
         /// Defines the <see cref="FontStyle"/> property.