Implements the “Executing requests” section of the GraphQL specification.
Returns either a synchronous ExecutionResult (if all encountered resolvers
are synchronous), or a Promise of an ExecutionResult that will eventually be
resolved and never rejected.
If the arguments to this function do not result in a legal execution context,
a GraphQLError will be thrown immediately explaining the invalid input.
Implements the “Executing requests” section of the GraphQL specification.
Returns either a synchronous ExecutionResult (if all encountered resolvers are synchronous), or a Promise of an ExecutionResult that will eventually be resolved and never rejected.
If the arguments to this function do not result in a legal execution context, a GraphQLError will be thrown immediately explaining the invalid input.