add tests

Author: jdconrad

server/src/test/java/org/elasticsearch/TransportVersionTests.java

@@ -391,4 +391,25 @@ public void testComment() {
         );
         assertThat(new TransportVersion(null, 1000000, null).supports(test3), is(true));
     }
+
+    public void testMoreLikeThis() {
+        IllegalStateException ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("to_child_lock_join_query"));
+        assertThat(
+            ise.getMessage(),
+            is(
+                "unknown transport version [to_child_lock_join_query]; "
+                    + "did you mean [to_child_block_join_query]? "
+                    + "if this is a new transport version, did you run './gradle generateTransportVersion'?"
+            )
+        );
+
+        ise = expectThrows(IllegalStateException.class, () -> TransportVersion.fromName("brand_new_version_unrelated_to_others"));
+        assertThat(
+            ise.getMessage(),
+            is(
+                "unknown transport version [brand_new_version_unrelated_to_others]; "
+                    + "if this is a new transport version, did you run './gradle generateTransportVersion'?"
+            )
+        );
+    }
 }