diff --git a/guix/tests.scm b/guix/tests.scm
index 16a426c4f9..749a4edd7a 100644
--- a/guix/tests.scm
+++ b/guix/tests.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2013, 2014, 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -334,18 +334,19 @@ (define-syntax with-derivation-substitute
 (define-syntax-rule (dummy-package name* extra-fields ...)
   "Return a \"dummy\" package called NAME*, with all its compulsory fields
 initialized with default values, and with EXTRA-FIELDS set as specified."
-  (package extra-fields ...
-           (name name*) (version "0") (source #f)
-           (build-system gnu-build-system)
-           (synopsis #f) (description #f)
-           (home-page #f) (license #f)))
+  (let ((p (package
+             (name name*) (version "0") (source #f)
+             (build-system gnu-build-system)
+             (synopsis #f) (description #f)
+             (home-page #f) (license #f))))
+    (package (inherit p) extra-fields ...)))
 
 (define-syntax-rule (dummy-origin extra-fields ...)
   "Return a \"dummy\" origin, with all its compulsory fields initialized with
 default values, and with EXTRA-FIELDS set as specified."
-  (origin extra-fields ...
-          (method #f) (uri "http://www.example.com")
-          (sha256 (base32 (make-string 52 #\x)))))
+  (let ((o (origin (method #f) (uri "http://www.example.com")
+                   (sha256 (base32 (make-string 52 #\x))))))
+    (origin (inherit o) extra-fields ...)))
 
 ;; Local Variables:
 ;; eval: (put 'call-with-derivation-narinfo 'scheme-indent-function 1)
diff --git a/tests/services.scm b/tests/services.scm
index 5827dee80d..44ad0022c6 100644
--- a/tests/services.scm
+++ b/tests/services.scm
@@ -1,5 +1,5 @@
 ;;; GNU Guix --- Functional package management for GNU
-;;; Copyright © 2015, 2016, 2017, 2018 Ludovic Courtès <ludo@gnu.org>
+;;; Copyright © 2015, 2016, 2017, 2018, 2019 Ludovic Courtès <ludo@gnu.org>
 ;;;
 ;;; This file is part of GNU Guix.
 ;;;
@@ -143,7 +143,7 @@ (define live-service
                            (default-value 'dflt)
                            (compose concatenate)
                            (extend cons)))
-         (t2 (service-type (name 't2) (extensions '())
+         (t2 (service-type (name 't2)
                            (default-value 'dflt2)
                            (compose concatenate)
                            (extend cons)