Hi Guys,

I think i might have found a bug, it seems like the QueryTraversal class doesn't work with union types:

java.lang.ClassCastException: graphql.schema.GraphQLUnionType cannot be cast to graphql.schema.GraphQLFieldsContainer at graphql.analysis.QueryTraversal.visitImpl(QueryTraversal.java:98) at graphql.analysis.QueryTraversal.visitField(QueryTraversal.java:165) at graphql.analysis.QueryTraversal.visitImpl(QueryTraversal.java:100) at graphql.analysis.QueryTraversal.visitField(QueryTraversal.java:165) at graphql.analysis.QueryTraversal.visitImpl(QueryTraversal.java:100) at graphql.analysis.QueryTraversal.visitField(QueryTraversal.java:165) at graphql.analysis.QueryTraversal.visitImpl(QueryTraversal.java:100) at graphql.analysis.QueryTraversal.visitPreOrder(QueryTraversal.java:64) at graphql.analysis.QueryTraversal.reducePreOrder(QueryTraversal.java:89) at graphql.analysis.MaxQueryDepthInstrumentation.lambda$beginValidation$1(MaxQueryDepthInstrumentation.java:31)

This is with the 4.2 release but it looks like the QueryTraversal class hasn't changed in 5.0 yet. Will take a look and see if i can work out a patch.

-David