Additional test changes

Author: alex-kulakov

Orm/Xtensive.Orm.Tests/Linq/OfTypeTest.cs

@@ -381,8 +381,6 @@ public void Test04()
         Assert.That(result1.Length, Is.EqualTo(2));
         new[] { 1000, 2000 }
           .ForEach(i => Assert.That(result1.Contains(i), Is.True));
-        Assert.That(result1.First(), Is.EqualTo(1000));
-        Assert.That(result1.Last(), Is.EqualTo(2000));
 
         var result2 = session.Query.All<B2ClassTable>().OfType<AClassTable>()
           .Select(x => x.Field2).ToArray();
@@ -801,21 +799,16 @@ public void Test14()
         var result1B = source2B.Union(source1B).Select(x => x.Field1).ToArray();
 
         Assert.That(result1A, Is.Not.Empty);
-        Assert.That(result1B.Length, Is.EqualTo(result1A.Length));
-        foreach (var item in result1B) {
-          Assert.That(result1A.Contains(item));
-        }
-
+        Assert.That(result1A.Length, Is.EqualTo(result1B.Length));
+        Assert.That(result1A.Intersect(result1B).Count(), Is.EqualTo(result1A.Length));
 
         var result2A = source1B.Union(source2B).ToArray().OfType<B3ClassTable>().Select(x => x.Field4)
           .ToArray();
         var result2B = source1B.Union(source2B).OfType<B3ClassTable>().Select(x => x.Field4).ToArray();
 
         Assert.That(result2A, Is.Not.Empty);
-        Assert.That(result2B.Length, Is.EqualTo(result2A.Length));
-        foreach (var item in result2B) {
-          Assert.That(result2A.Contains(item));
-        }
+        Assert.That(result2A.Length, Is.EqualTo(result2B.Length));
+        Assert.That(result2A.Intersect(result2B).Count(), Is.EqualTo(result2A.Length));
 
         var result3 = session.Query.All<AClassTable>().OfType<AConcreteTable>().ToArray();
         Assert.That(result3, Is.Empty);
@@ -836,21 +829,17 @@ public void Test14()
         var result1B = source2B.Union(source1B).Select(x => x.Field1).ToArray();
 
         Assert.That(result1A, Is.Not.Empty);
-        Assert.That(result1B.Length, Is.EqualTo(result1A.Length));
-        foreach (var item in result1B) {
-          Assert.That(result1A.Contains(item));
-        }
+        Assert.That(result1A.Length, Is.EqualTo(result1B.Length));
+        Assert.That(result1A.Intersect(result1B).Count(), Is.EqualTo(result1A.Length));
 
 
         var result2A = source1B.Union(source2B).ToArray().OfType<B3ConcreteTable>().Select(x => x.Field4)
           .ToArray();
         var result2B = source1B.Union(source2B).OfType<B3ConcreteTable>().Select(x => x.Field4).ToArray();
 
         Assert.That(result2A, Is.Not.Empty);
-        Assert.That(result2B.Length, Is.EqualTo(result2A.Length));
-        foreach (var item in result2B) {
-          Assert.That(result2A.Contains(item));
-        }
+        Assert.That(result2A.Length, Is.EqualTo(result2B.Length));
+        Assert.That(result2A.Intersect(result2B).Count(), Is.EqualTo(result2A.Length));
 
         var result3 = session.Query.All<AConcreteTable>().OfType<ASingleTable>().ToArray();
         Assert.That(result3, Is.Empty);
@@ -871,20 +860,16 @@ public void Test14()
         var result1B = source2B.Union(source1B).Select(x => x.Field1).ToArray();
 
         Assert.That(result1A, Is.Not.Empty);
-        Assert.That(result1B.Length, Is.EqualTo(result1A.Length));
-        foreach (var item in result1B) {
-          Assert.That(result1A.Contains(item));
-        }
+        Assert.That(result1A.Length, Is.EqualTo(result1B.Length));
+        Assert.That(result1A.Intersect(result1B).Count(), Is.EqualTo(result1A.Length));
 
         var result2A = source1B.Union(source2B).ToArray().OfType<B3SingleTable>().Select(x => x.Field4)
           .ToArray();
         var result2B = source1B.Union(source2B).OfType<B3SingleTable>().Select(x => x.Field4).ToArray();
 
         Assert.That(result2A, Is.Not.Empty);
-        Assert.That(result2B.Length, Is.EqualTo(result2A.Length));
-        foreach (var item in result2B) {
-          Assert.That(result2A.Contains(item));
-        }
+        Assert.That(result2A.Length, Is.EqualTo(result2B.Length));
+        Assert.That(result2A.Intersect(result2B).Count(), Is.EqualTo(result2A.Length));
 
         var result3 = session.Query.All<ASingleTable>().OfType<AClassTable>().ToArray();
         Assert.That(result3, Is.Empty);