+(test-assert "instantiate-missing-services, indirect"
+ (let* ((t1 (service-type (name 't1) (extensions '())
+ (default-value 'dflt)
+ (compose concatenate)
+ (extend cons)))
+ (t2 (service-type (name 't2)
+ (default-value 'dflt2)
+ (compose concatenate)
+ (extend cons)
+ (extensions
+ (list (service-extension t1 list)))))
+ (t3 (service-type (name 't3)
+ (extensions
+ (list (service-extension t2 list)))))
+ (s1 (service t1))
+ (s2 (service t2))
+ (s3 (service t3 42))
+ (== (cut lset= equal? <...>)))
+ (and (== (list s1 s2 s3)
+ (instantiate-missing-services (list s3)))
+ (== (list s1 s2 s3)
+ (instantiate-missing-services (list s1 s3)))
+ (== (list s1 s2 s3)
+ (instantiate-missing-services (list s2 s3))))))
+