TST: special: add a few infinity checks

Author: pv

scipy/special/tests/test_basic.py

@@ -137,6 +137,8 @@ def test_betaln(self):
         assert_equal(cephes.betaln(1,1),0.0)
     def test_betaincinv(self):
         assert_equal(cephes.betaincinv(1,1,1),1.0)
+    def test_beta_inf(self):
+        assert_(np.isinf(special.beta(-1, 2)))
 
     def test_btdtr(self):
         assert_equal(cephes.btdtr(1,1,1),1.0)
@@ -1236,6 +1238,10 @@ def test_rgamma(self):
         rlgam = 1/special.gamma(8)
         assert_almost_equal(rgam,rlgam,8)
 
+    def test_infinity(self):
+        assert_(np.isinf(special.gamma(-1)))
+        assert_equal(special.rgamma(-1), 0)
+
 class TestHankel(TestCase):
 
     def test_negv1(self):