diff --git a/tests/test_basis_rotation.py b/tests/test_basis_rotation.py
index 52fce8a..242c795 100644
--- a/tests/test_basis_rotation.py
+++ b/tests/test_basis_rotation.py
@@ -11,21 +11,32 @@
 from qibochem.driver.molecule import Molecule
 from qibochem.measurement.expectation import expectation
 
+def test_swap_matrices():
+    """Test for swap_matrices"""
+    permutations = [[(0,1),(2,3)]]
+    n_qubits = 4
+    smat = basis_rotation.swap_matrices(permutations, n_qubits)
+    ref_smat = np.array([[0., 1., 0., 0.],
+                         [1., 0., 0., 0.],
+                         [0., 0., 0., 1.],
+                         [0., 0., 1., 0.]])
+
+    assert np.allclose(smat, ref_smat)
+
 
 def test_unitary_rot_matrix():
     """Test for unitary rotation matrix"""
     occ = [0]
     vir = [1, 2]
-    parameters = np.zeros(len(occ) * len(vir))
+    parameters = np.zeros(len(occ)*len(vir))
     parameters += 0.1
     u = basis_rotation.unitary_rot_matrix(parameters, occ, vir)
-    ref_u = np.array(
-        [[0.99001666, 0.099667, 0.099667], [-0.099667, 0.99500833, -0.00499167], [-0.099667, -0.00499167, 0.99500833]]
-    )
-
+    ref_u = np.array([[ 0.99001666, 0.099667, 0.099667],
+                      [-0.099667, 0.99500833, -0.00499167],
+                      [-0.099667, -0.00499167, 0.99500833]])
+    
     assert np.allclose(u, ref_u)
 
-
 def test_br_ansatz():
     """Test of basis rotation ansatz against hardcoded HF energies"""
     h2_ref_energy = -1.117349035
diff --git a/tests/test_ucc.py b/tests/test_ucc.py
index ea4094f..e806455 100644
--- a/tests/test_ucc.py
+++ b/tests/test_ucc.py
@@ -1,4 +1,5 @@
 import numpy as np
+import pytest
 from scipy.optimize import minimize
 
 from qibochem.ansatz.hf_reference import hf_circuit