fix(m2): fix repository tag model issue

YKanBan.Tests/Models/RgbColorTests.cs

@@ -0,0 +1,72 @@
+using YKanBan.Models;
+
+namespace YKanBan.Tests.Models;
+
+/// <summary>Tests for the RGB color value type and its #RRGGBB text conversions.</summary>
+[TestClass]
+public class RgbColorTests
+{
+    [TestMethod]
+    public void ParseExtractsComponents()
+    {
+        RgbColor color = RgbColor.Parse("#ff0a00");
+        Assert.AreEqual(new RgbColor(0xFF, 0x0A, 0x00), color);
+    }
+
+    [TestMethod]
+    public void ParseAcceptsUppercaseAndMixedCaseHex()
+    {
+        Assert.AreEqual(new RgbColor(0xAB, 0xCD, 0xEF), RgbColor.Parse("#ABCDEF"));
+        Assert.AreEqual(new RgbColor(0xAB, 0xCD, 0xEF), RgbColor.Parse("#aBcDeF"));
+    }
+
+    [TestMethod]
+    [DataRow("ff0000")]
+    [DataRow("#ff000")]
+    [DataRow("#ff00000")]
+    [DataRow("#gg0000")]
+    [DataRow("#ff 000")]
+    [DataRow(" #ff0000")]
+    [DataRow("#ff0000 ")]
+    [DataRow("#")]
+    [DataRow("")]
+    public void TryParseRejectsMalformedText(string text)
+    {
+        Assert.IsFalse(RgbColor.TryParse(text, out _));
+    }
+
+    [TestMethod]
+    public void TryParseRejectsNull()
+    {
+        Assert.IsFalse(RgbColor.TryParse(null, out _));
+    }
+
+    [TestMethod]
+    public void ParseThrowsFormatExceptionForMalformedText()
+    {
+        Assert.ThrowsExactly<FormatException>(() => RgbColor.Parse("red"));
+    }
+
+    [TestMethod]
+    public void ToStringProducesCanonicalLowercaseForm()
+    {
+        Assert.AreEqual("#ee0a0a", new RgbColor(0xEE, 0x0A, 0x0A).ToString());
+
+        // Uppercase input normalizes to the canonical lowercase output.
+        Assert.AreEqual("#ee0a0a", RgbColor.Parse("#EE0A0A").ToString());
+    }
+
+    [TestMethod]
+    public void EqualityComparesComponents()
+    {
+        Assert.AreEqual(RgbColor.Parse("#ff0000"), RgbColor.Parse("#FF0000"));
+        Assert.AreNotEqual(RgbColor.Parse("#ff0000"), RgbColor.Parse("#ff0001"));
+    }
+
+    [TestMethod]
+    public void TextRoundTripPreservesColor()
+    {
+        RgbColor original = new(0x12, 0x34, 0x56);
+        Assert.AreEqual(original, RgbColor.Parse(original.ToString()));
+    }
+}