add test__evdns.py

greentest/test__evdns.py

+#!/usr/bin/python
+import greentest
+from gevent import evdns
+from gevent import core
+from gevent import socket
+
+funcs = [evdns.resolve_ipv4, evdns.resolve_ipv6,
+         evdns.resolve_reverse, evdns.resolve_reverse_ipv6]
+
+
+class TestNoSwitch(greentest.TestCase):
+
+    switch_expected = False
+
+    def test_type_error(self):
+        for func in funcs:
+            self.assertRaises(TypeError, func, None)
+            self.assertRaises(TypeError, func, 15)
+            self.assertRaises(TypeError, func, object())
+
+    def test_dns_err_to_string(self):
+        for err in range(-100, 100):
+            result = core.dns_err_to_string(err)
+            assert result, result
+            assert isinstance(result, str)
+
+
+class TestSwitch(greentest.TestCase):
+
+    switch_expected = True
+
+    def test_empty_string(self):
+        self.assertRaises(evdns.DNSError, evdns.resolve_ipv4, '')
+        self.assertRaises(evdns.DNSError, evdns.resolve_ipv6, '')
+        self.assertRaises(evdns.DNSError, evdns.resolve_reverse, '')
+        self.assertRaises(evdns.DNSError, evdns.resolve_reverse_ipv6, '')
+
+
+if __name__ == '__main__':
+    greentest.main()
+