TODO: add matching when bulk optional fields are allowed
alongside other fields.
-- in.cue --
{[X=string]: baz: X}
bar: {}
@test(eq, {bar: baz: "bar"})
-- out/eval/stats --
Leaks:  0
Freed:  3
Reused: 0
Allocs: 3
Retain: 0

Unifications: 3
Conjuncts:    5
Disjuncts:    3
