diff --git a/tests/test_helpers.py b/tests/test_helpers.py
new file mode 100644
index 0000000..8962060
--- /dev/null
+++ b/tests/test_helpers.py
@@ -0,0 +1,85 @@
+import pytest
+import aiosocks
+
+
+def test_socks4_auth1():
+    with pytest.raises(ValueError):
+        aiosocks.Socks4Auth(None)
+
+
+def test_socks4_auth2():
+    auth = aiosocks.Socks4Auth('usr', encoding='ascii')
+    assert auth.login == b'usr'
+
+
+def test_socks4_auth3():
+    auth = aiosocks.Socks4Auth('usrё', encoding='utf-8')
+    assert auth.login == b'usr\xd1\x91'
+
+
+def test_socks5_auth1():
+    with pytest.raises(ValueError):
+        aiosocks.Socks5Auth(None, '')
+
+
+def test_socks5_auth2():
+    with pytest.raises(ValueError):
+        aiosocks.Socks5Auth('', None)
+
+
+def test_socks5_auth3():
+    auth = aiosocks.Socks5Auth('usr', 'pwd', encoding='ascii')
+    assert auth.login == b'usr'
+    assert auth.password == b'pwd'
+
+
+def test_socks5_auth4():
+    auth = aiosocks.Socks5Auth('usrё', 'pwdё', encoding='utf-8')
+    assert auth.login == b'usr\xd1\x91'
+    assert auth.password == b'pwd\xd1\x91'
+
+
+def test_socks4_addr1():
+    with pytest.raises(ValueError):
+        aiosocks.Socks4Addr(None)
+
+
+def test_socks4_addr2():
+    addr = aiosocks.Socks4Addr('localhost')
+    assert addr.host == 'localhost'
+    assert addr.port == 1080
+
+
+def test_socks4_addr3():
+    addr = aiosocks.Socks4Addr('localhost', 1)
+    assert addr.host == 'localhost'
+    assert addr.port == 1
+
+
+def test_socks4_addr4():
+    addr = aiosocks.Socks4Addr('localhost', None)
+    assert addr.host == 'localhost'
+    assert addr.port == 1080
+
+
+def test_socks5_addr1():
+    with pytest.raises(ValueError):
+        aiosocks.Socks5Addr(None)
+
+
+def test_socks5_addr2():
+    addr = aiosocks.Socks5Addr('localhost')
+    assert addr.host == 'localhost'
+    assert addr.port == 1080
+
+
+def test_socks5_addr3():
+    addr = aiosocks.Socks5Addr('localhost', 1)
+    assert addr.host == 'localhost'
+    assert addr.port == 1
+
+
+def test_socks5_addr4():
+    addr = aiosocks.Socks5Addr('localhost', None)
+    assert addr.host == 'localhost'
+    assert addr.port == 1080