From 5ec758d790360bc81371b88409d5b263e288cba9 Mon Sep 17 00:00:00 2001
From: Nikita Tsukanov <keks9n@gmail.com>
Date: Wed, 10 May 2023 14:58:58 +0600
Subject: [PATCH] Fix TokenParser

---
 .../Composition/Expressions/TokenParser.cs    |  2 +-
 .../CompositionAnimationParserTests.cs        | 39 +++++++++++++++++++
 2 files changed, 40 insertions(+), 1 deletion(-)
 create mode 100644 tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationParserTests.cs

diff --git a/src/Avalonia.Base/Rendering/Composition/Expressions/TokenParser.cs b/src/Avalonia.Base/Rendering/Composition/Expressions/TokenParser.cs
index 8ecc0028ce..3991300fb5 100644
--- a/src/Avalonia.Base/Rendering/Composition/Expressions/TokenParser.cs
+++ b/src/Avalonia.Base/Rendering/Composition/Expressions/TokenParser.cs
@@ -243,7 +243,7 @@ namespace Avalonia.Rendering.Composition.Expressions
                 else if (ch == '-')
                 {
                     if (len != 0)
-                        return false;
+                        break;
                     len = c + 1;
                 }
                 else
diff --git a/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationParserTests.cs b/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationParserTests.cs
new file mode 100644
index 0000000000..fc6ea969d8
--- /dev/null
+++ b/tests/Avalonia.Base.UnitTests/Composition/CompositionAnimationParserTests.cs
@@ -0,0 +1,39 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Reflection;
+using Avalonia.Animation.Easings;
+using Avalonia.Base.UnitTests.Rendering;
+using Avalonia.Rendering;
+using Avalonia.Rendering.Composition;
+using Avalonia.Rendering.Composition.Expressions;
+using Avalonia.Rendering.Composition.Server;
+using Avalonia.Threading;
+using Avalonia.UnitTests;
+using Xunit;
+using Xunit.Sdk;
+
+namespace Avalonia.Base.UnitTests.Composition;
+
+public class CompositionAnimationParserTests
+{
+    [Theory,
+     InlineData("Vector3(0.5+(4.0-0.5)* -2, 1, 0).X", -6.5)]
+    public void EvaluatesExpressionCorrectly(string expression, double value)
+    {
+        var expr = ExpressionParser.Parse(expression);
+        var ctx = new ExpressionEvaluationContext
+        {
+            ForeignFunctionInterface = BuiltInExpressionFfi.Instance,
+        };
+        var res = expr.Evaluate(ref ctx);
+        double doubleRes;
+        if (res.Type == VariantType.Scalar)
+            doubleRes = res.Scalar;
+        else if (res.Type == VariantType.Double)
+            doubleRes = res.Double;
+        else
+            throw new Exception("Invalid result type: " + res.Type);
+        Assert.Equal(value, doubleRes);
+    }
+}
\ No newline at end of file