From 6da6f69e7acc74fb72738c08518fe822b0f0db83 Mon Sep 17 00:00:00 2001
From: Shay Rojansky <roji@roji.org>
Date: Sat, 16 Nov 2019 12:24:25 -0800
Subject: [PATCH] Switch to using EqualsExact in geometry comparer

Fixes #18921
---
 .../ChangeTracking/GeometryValueComparer.cs   |  2 +-
 .../RelationalGeometryTypeMappingTest.cs      | 57 +++++++++++++++++++
 2 files changed, 58 insertions(+), 1 deletion(-)
 create mode 100644 test/EFCore.Relational.Tests/Storage/RelationalGeometryTypeMappingTest.cs

diff --git a/src/EFCore/ChangeTracking/GeometryValueComparer.cs b/src/EFCore/ChangeTracking/GeometryValueComparer.cs
index 1453fd7e6e7..10c5a635524 100644
--- a/src/EFCore/ChangeTracking/GeometryValueComparer.cs
+++ b/src/EFCore/ChangeTracking/GeometryValueComparer.cs
@@ -31,7 +31,7 @@ private static Expression<Func<TGeometry, TGeometry, bool>> GetEqualsExpression(
             return Expression.Lambda<Func<TGeometry, TGeometry, bool>>(
                 Expression.Call(
                     left,
-                    typeof(TGeometry).GetRuntimeMethod("EqualsTopologically", new[] { typeof(TGeometry) }),
+                    typeof(TGeometry).GetRuntimeMethod("EqualsExact", new[] { typeof(TGeometry) }),
                     right),
                 left,
                 right);
diff --git a/test/EFCore.Relational.Tests/Storage/RelationalGeometryTypeMappingTest.cs b/test/EFCore.Relational.Tests/Storage/RelationalGeometryTypeMappingTest.cs
new file mode 100644
index 00000000000..4ca3925bcb0
--- /dev/null
+++ b/test/EFCore.Relational.Tests/Storage/RelationalGeometryTypeMappingTest.cs
@@ -0,0 +1,57 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
+using NetTopologySuite.Geometries;
+using Xunit;
+
+namespace Microsoft.EntityFrameworkCore.Storage
+{
+    public class RelationalGeometryTypeMappingTest
+    {
+        [ConditionalFact]
+        public void Comparer_uses_exact_comparison()
+        {
+            var geometry1 = new GeometryCollection(new[]
+            {
+                new Point(1, 2),
+                new Point(3, 4)
+            });
+            var geometry2 = new GeometryCollection(new[]
+            {
+                new Point(3, 4),
+                new Point(1, 2)
+            });
+
+            var comparer = new FakeRelationalGeometryTypeMapping<GeometryCollection>().Comparer;
+            Assert.False(comparer.Equals(geometry1, geometry2));
+        }
+
+        private class FakeRelationalGeometryTypeMapping<TGeometry> : RelationalGeometryTypeMapping<TGeometry, TGeometry>
+        {
+            public FakeRelationalGeometryTypeMapping()
+                : base(new NullValueConverter(), "geometry")
+            {
+            }
+
+            private FakeRelationalGeometryTypeMapping(RelationalTypeMappingParameters parameters)
+                : base(parameters, new NullValueConverter())
+            {
+            }
+
+            protected override RelationalTypeMapping Clone(RelationalTypeMappingParameters parameters)
+                => new FakeRelationalGeometryTypeMapping<TGeometry>(parameters);
+
+            protected override Type WKTReaderType { get; }
+            protected override string AsText(object value) => throw new NotImplementedException();
+            protected override int GetSrid(object value) => throw new NotImplementedException();
+
+            class NullValueConverter : ValueConverter<TGeometry, TGeometry>
+            {
+                public NullValueConverter() : base(t => t, t => t) {}
+            }
+        }
+
+    }
+}