make tests nicer

kwant/linalg/tests/test_mumps.py

@@ -74,10 +74,8 @@ def test_error_minus_9(r=10):
 
     sys = Builder()
     sys[graphene.shape(circle, (0,0))] = -0.0001
-    for kind in (HoppingKind((0, 0), b, a),
-                 HoppingKind((0, 1), b, a),
-                 HoppingKind((-1, 1), b, a)):
-        sys[kind] = - 1
+    for kind in [((0, 0), b, a), ((0, 1), b, a), ((-1, 1), b, a)]:
+        sys[HoppingKind(*kind)] = - 1
 
     ham = sys.finalized().hamiltonian_submatrix(sparse=True)
 

kwant/tests/test_plotter.py

@@ -49,9 +49,8 @@ def sys_2d(W=3, r1=3, r2=8):
 
 def sys_3d(W=3, r1=2, r2=4, a=1, t=1.0):
     lat = kwant.lattice.general(((a, 0, 0), (0, a, 0), (0, 0, a)))
-    lat.nearest = [kwant.builder.HoppingKind((1, 0, 0), lat),
-                   kwant.builder.HoppingKind((0, 1, 0), lat),
-                   kwant.builder.HoppingKind((0, 0, 1), lat)]
+    lat.nearest = [kwant.builder.HoppingKind(*kind) for kind in
+                   [((1, 0, 0), lat), ((0, 1, 0), lat), ((0, 0, 1), lat)]]
     sys = kwant.Builder()
 
     def ring(pos):