(test-begin "services")
+(test-assert "service-back-edges"
+ (let* ((t1 (service-type (name 't1) (extensions '())
+ (compose +) (extend *)))
+ (t2 (service-type (name 't2)
+ (extensions
+ (list (service-extension t1 (const '()))))
+ (compose +) (extend *)))
+ (t3 (service-type (name 't3)
+ (extensions
+ (list (service-extension t2 identity)
+ (service-extension t1 list)))))
+ (s1 (service t1 #t))
+ (s2 (service t2 #t))
+ (s3 (service t3 #t))
+ (e (service-back-edges (list s1 s2 s3))))
+ (and (lset= eq? (e s1) (list s2 s3))
+ (lset= eq? (e s2) (list s3))
+ (null? (e s3)))))
+
(test-equal "fold-services"
;; Make sure 'fold-services' returns the right result. The numbers come
;; from services of type T3; 'xyz 60' comes from the service of type T2,