1 files changed, 32 insertions, 0 deletions
diff --git a/tests/Jellyfin.Model.Tests/Extensions/StringHelperTests.cs b/tests/Jellyfin.Model.Tests/Extensions/StringHelperTests.cs
new file mode 100644
index 000000000..0a4e060df
--- /dev/null
+++ b/tests/Jellyfin.Model.Tests/Extensions/StringHelperTests.cs
@@ -0,0 +1,32 @@
+using System;
+using FsCheck;
+using FsCheck.Xunit;
+using MediaBrowser.Model.Extensions;
+using Xunit;
+
+namespace Jellyfin.Model.Tests.Extensions
+{
+    public class StringHelperTests
+    {
+        [Theory]
+        [InlineData("", "")]
+        [InlineData("banana", "Banana")]
+        [InlineData("Banana", "Banana")]
+        [InlineData("ä", "Ä")]
+        [InlineData("\027", "\027")]
+        public void StringHelper_ValidArgs_Success(string input, string expectedResult)
+        {
+            Assert.Equal(expectedResult, StringHelper.FirstToUpper(input));
+        }
+
+        [Property]
+        public Property FirstToUpper_RandomArg_Correct(NonEmptyString input)
+        {
+            var result = StringHelper.FirstToUpper(input.Item);
+
+            // We check IsLower instead of IsUpper because both return false for non-letters
+            return (!char.IsLower(result[0])).Label("First char is uppercase")
+                .And(input.Item.Length == 1 || result[1..].Equals(input.Item[1..], StringComparison.Ordinal)).Label("Remaining chars are unmodified");
+        }
+    }
+}