Draft: [DRIVER-788] Validate SELECT without FROM support

src/Cassandra.IntegrationTests/Core/SelectWithoutFromTests.cs

@@ -0,0 +1,71 @@
+//
+//      Copyright (C) DataStax Inc.
+//
+//   Licensed under the Apache License, Version 2.0 (the "License");
+//   you may not use this file except in compliance with the License.
+//   You may obtain a copy of the License at
+//
+//      http://www.apache.org/licenses/LICENSE-2.0
+//
+//   Unless required by applicable law or agreed to in writing, software
+//   distributed under the License is distributed on an "AS IS" BASIS,
+//   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+//   See the License for the specific language governing permissions and
+//   limitations under the License.
+//
+
+using System;
+using System.Linq;
+using Cassandra.IntegrationTests.TestBase;
+using Cassandra.Tests;
+using NUnit.Framework;
+using Assert = NUnit.Framework.Legacy.ClassicAssert;
+
+namespace Cassandra.IntegrationTests.Core
+{
+    [TestFixture, Category(TestCategory.Short), Category(TestCategory.RealCluster), Category(TestCategory.ServerApi)]
+    public class SelectWithoutFromTests : SharedClusterTest
+    {
+        [Test]
+        public void Should_Execute_Select_Without_From()
+        {
+            RowSet result;
+            try
+            {
+                result = Session.Execute("SELECT 1");
+            }
+            catch (QueryValidationException ex) when (ex is InvalidQueryException || ex is SyntaxError)
+            {
+                Assert.Ignore("Server does not support SELECT without FROM");
+                return;
+            }
+
+            AssertLiteralResult(result);
+            AssertNowResult(Session.Execute("SELECT now()"));
+
+            var prepared = Session.Prepare("SELECT 1");
+            AssertLiteralResult(Session.Execute(prepared.Bind()));
+
+            prepared = Session.Prepare("SELECT now()");
+            AssertNowResult(Session.Execute(prepared.Bind()));
+        }
+
+        private static void AssertLiteralResult(RowSet result)
+        {
+            var row = result.Single();
+            Assert.AreEqual(1, result.Columns.Length);
+            Assert.AreEqual("1", result.Columns[0].Name);
+            Assert.AreEqual(ColumnTypeCode.Int, result.Columns[0].TypeCode);
+            Assert.AreEqual(1, row.GetValue<int>(0));
+        }
+
+        private static void AssertNowResult(RowSet result)
+        {
+            var row = result.Single();
+            Assert.AreEqual(1, result.Columns.Length);
+            Assert.AreEqual("now()", result.Columns[0].Name);
+            Assert.AreEqual(ColumnTypeCode.Timeuuid, result.Columns[0].TypeCode);
+            Assert.AreNotEqual(Guid.Empty, row.GetValue<Guid>(0));
+        }
+    }
+}