Tests for generateSchema have too much code repetition

[helfer]

It would make sense to rewrite the tests in this way:

• Define a complete shorthand once for all tests
• Define some resolve functions once for all tests
• Write a helper function that given the expected result generates and runs query and checks the result

(PS: I probably won't do this any time soon, but PRs very much appreciated)

[helfer]

Closing this since there's more important work to do. The tests work and they probably won't change. If we revisit the file, then we can refactor it when we get to it.