diff --git a/unittest/force-styles/tests/data.fourmol b/unittest/force-styles/tests/data.fourmol
index 386ad81c49..1415230e9c 100644
--- a/unittest/force-styles/tests/data.fourmol
+++ b/unittest/force-styles/tests/data.fourmol
@@ -46,6 +46,19 @@ Angle Coeffs # zero
 3 120
 4 108.5
 
+Dihedral Coeffs # zero
+
+1
+2
+3
+4
+5
+
+Improper Coeffs # zero
+
+1
+2
+
 Atoms # full
 
 10 2 1 7.0000000000000007e-02 2.0185283555536988e+00 -1.4283966846517357e+00 -9.6733527271133024e-01 0 0 0
diff --git a/unittest/force-styles/tests/in.fourmol b/unittest/force-styles/tests/in.fourmol
index 943c0466e6..df936da78e 100644
--- a/unittest/force-styles/tests/in.fourmol
+++ b/unittest/force-styles/tests/in.fourmol
@@ -28,5 +28,3 @@ dihedral_style   ${dihedral_style}
 improper_style   ${improper_style}
 
 read_data        ${data_file}
-if "${dihedral_style} == zero" then "dihedral_coeff *"
-if "${improper_style} == zero" then "improper_coeff *"