Fixes to support multi-dimensional arrays

src/EFCore.Relational/Storage/Internal/DbParameterCollectionExtensions.cs

@@ -164,20 +164,25 @@ private static void FormatParameterValue(StringBuilder builder, object? paramete
             case IList list:
                 builder.Append("{ ");
 
-                for (var i = 0; i < list.Count; i++)
+                // Note: multi-dimensional arrays implement non-generic IList. They do not support indexing, but do support enumeration.
+                var isFirst = true;
+                foreach (var element in list.Cast<object>().Take(5))
                 {
-                    if (i > 4)
+                    if (isFirst)
                     {
-                        builder.Append("...");
-                        break;
+                        isFirst = false;
                     }
-
-                    FormatParameterValue(builder, list[i]);
-
-                    if (i < list.Count - 1)
+                    else
                     {
                         builder.Append(", ");
                     }
+
+                    FormatParameterValue(builder, element);
+                }
+
+                if (list.Count > 5)
+                {
+                    builder.Append(", ...");
                 }
 
                 builder.Append(" }");

src/EFCore/ChangeTracking/ValueComparer`.cs

@@ -90,6 +90,8 @@ public ValueComparer(
         var param1 = Expression.Parameter(type, "v1");
         var param2 = Expression.Parameter(type, "v2");
 
+        // We exclude multi-dimensional arrays even though they're IStructuralEquatable because of
+        // https://github.com/dotnet/runtime/issues/66472
         if (typeof(IStructuralEquatable).IsAssignableFrom(type))
         {
             return Expression.Lambda<Func<T?, T?, bool>>(
@@ -172,7 +174,8 @@ public ValueComparer(
     protected static Expression<Func<T, T>> CreateDefaultSnapshotExpression(bool favorStructuralComparisons)
     {
         if (!favorStructuralComparisons
-            || !typeof(T).IsArray)
+            || !typeof(T).IsArray
+            || typeof(T).GetArrayRank() != 1)
         {
             return v => v;
         }

test/EFCore.Tests/Storage/ValueComparerTest.cs

@@ -56,6 +56,7 @@ public void Throws_for_comparer_with_wrong_type()
     [InlineData(typeof(float), (float)1, (float)2, null)]
     [InlineData(typeof(double), (double)1, (double)2, null)]
     [InlineData(typeof(JustAnEnum), JustAnEnum.A, JustAnEnum.B, null)]
+    [InlineData(typeof(int[]), new[] { 1, 2 }, new[] { 3, 4 }, null)]
     public ValueComparer Default_comparer_works_for_normal_types(Type type, object value1, object value2, int? hashCode)
         => CompareTest(type, value1, value2, hashCode);
 
@@ -94,8 +95,6 @@ private static ValueComparer CompareTest(Type type, object value1, object value2
         Assert.False(keyComparer.Equals(null, value2));
         Assert.True(keyComparer.Equals(null, null));
 
-        Assert.Equal(hashCode ?? value1.GetHashCode(), keyComparer.GetHashCode(value1));
-
         return comparer;
     }