Github user fhueske commented on a diff in the pull request:
https://github.com/apache/flink/pull/5240#discussion_r163071117
--- Diff:
flink-libraries/flink-table/src/test/scala/org/apache/flink/table/api/DescriptorsTest.scala
---
@@ -0,0 +1,245 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you 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
+ *
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+ */
+
+package org.apache.flink.table.api
+
+import _root_.java.util
+
+import org.apache.flink.api.common.typeinfo.TypeInformation
+import org.apache.flink.api.java.typeutils.TypeExtractor
+import org.apache.flink.table.descriptors._
+import org.apache.flink.table.plan.stats.{ColumnStats, TableStats}
+import org.apache.flink.table.utils.TableTestBase
+import org.junit.Assert.assertEquals
+import org.junit.Test
+
+class DescriptorsTest extends TableTestBase {
--- End diff --
I would move the tests to a separate class per descriptor.
If we add a `validate` method to `Descriptor` this needs to be tested as
well.
---
