diff --git a/tests/fits_test.py b/tests/fits_test.py
index 4018abb8..374f590a 100644
--- a/tests/fits_test.py
+++ b/tests/fits_test.py
@@ -97,6 +97,35 @@ def test_least_squares_num_grad():
     assert(num[1] == auto[1])
 
 
+def test_prior_fit_num_grad():
+    x = []
+    y = []
+    for i in range(2, 5):
+        x.append(i * 0.01)
+        y.append(pe.pseudo_Obs(i * 0.01, 0.0001, "ens"))
+
+    num = pe.fits.least_squares(x, y, lambda a, x: np.exp(a[0] * x) + a[1], num_grad=True, priors=y[:2])
+    auto = pe.fits.least_squares(x, y, lambda a, x: anp.exp(a[0] * x) + a[1], num_grad=False, piors=y[:2])
+
+
+def test_least_squares_num_grad():
+    x = []
+    y = []
+    for i in range(2, 5):
+        x.append(i * 0.01)
+        y.append(pe.pseudo_Obs(i * 0.01, 0.0001, "ens"))
+
+    num = pe.fits.least_squares(x, y, lambda a, x: np.exp(a[0] * x) + a[1], num_grad=True)
+    auto = pe.fits.least_squares(x, y, lambda a, x: anp.exp(a[0] * x) + a[1], num_grad=False)
+
+    assert(num[0] == auto[0])
+    assert(num[1] == auto[1])
+
+
+    assert(num[0] == auto[0])
+    assert(num[1] == auto[1])
+
+
 def test_total_least_squares_num_grad():
     x = []
     y = []