tests refactoring

tests/test_signature.py

@@ -6,65 +6,81 @@
 
 
 @pytest.fixture(scope='module')
-def state():
-    signature = (
-        '0947c88ce16d078dde4a2aded1fe4627643a378757dccc3428c19569fea99542'
-    )
-    prefix = 'HMAC-SHA256'
-    access_key = 'my access key'
-    secret_key = 'my secret key'
-    message = '1457369891.672671'
-    full_signature = '{} {}:{}'.format(prefix, access_key, signature)
-    return dict(message=message,
-                access_key=access_key,
-                secret_key=secret_key,
-                signature=signature,
-                full_signature=full_signature)
-
-
-def test_generate_key():
-    key_settings = {
+def _prefix():
+    return 'HMAC-SHA256'
+
+
+@pytest.fixture(scope='module')
+def _access_key():
+    return 'my access key'
+
+
+@pytest.fixture(scope='module')
+def _secret_key():
+    return 'my secret key'
+
+
+@pytest.fixture(scope='module')
+def _message():
+    return '1457369891.672671'
+
+
+@pytest.fixture(scope='module')
+def _signature():
+    return '0947c88ce16d078dde4a2aded1fe4627643a378757dccc3428c19569fea99542'
+
+
+@pytest.fixture(scope='module')
+def _full_signature(_prefix, _access_key, _signature):
+    return '{} {}:{}'.format(_prefix, _access_key, _signature)
+
+
+@pytest.fixture(scope='module')
+def _key_settings():
+    return {
         'key_length': 5,
         'key_chars': 'abc123',
     }
-    key = generate_key(**key_settings)
-    assert (len(key) == key_settings['key_length'],
+
+
+def test_generate_key(_key_settings):
+    key = generate_key(**_key_settings)
+    assert (len(key) == _key_settings['key_length'],
             'Key should have defined length')
-    assert (not set(key) - set(key_settings['key_chars']),
+    assert (not set(key) - set(_key_settings['key_chars']),
             'Key should contain only defined chars')
 
 
-def test_create_signature(state):
-    expected_result = state['full_signature']
-    actual_result = create_signature(state['access_key'], state['secret_key'],
-                                     state['message'])
+def test_create_signature(_access_key, _secret_key, _message, _full_signature):
+    expected_result = _full_signature
+    actual_result = create_signature(_access_key, _secret_key, _message)
     assert actual_result == expected_result, 'Should produce correct signature'
 
 
-def test_parse_signature(state):
-    access_key, signature = parse_signature(state['full_signature'])
+def test_parse_signature(_access_key, _signature, _full_signature):
+    access_key, signature = parse_signature(_full_signature)
     assert (
-        (access_key, signature) == (state['access_key'], state['signature']),
+        (access_key, signature) == (_access_key, _signature),
         'Should parse access key and signature correctly'
     )
     with pytest.raises(ValueError) as e:
-        parse_signature(state['full_signature'], auth_header_prefix='my pref')
+        parse_signature(_full_signature, auth_header_prefix='WRONG_PREFIX')
     assert 'Invalid prefix value in `Authorization` header.' in str(e.value)
 
 
-def test_verify_signature(state):
-    valid = (state['access_key'], state['secret_key'], state['message'],
-             state['full_signature'])
-    invalid = (
-        (state['access_key'], state['secret_key'], state['message'] + 'x',
-         state['full_signature']),
-        (state['access_key'] + 'x', state['secret_key'],
-         state['message'], state['full_signature']),
-        (state['access_key'], state['secret_key'] + 'x',
-         state['message'], state['full_signature']),
-        (state['access_key'], state['secret_key'], state['message'],
-         state['full_signature'] + 'x')
-    )
+def test_verify_signature(_access_key, _secret_key, _message, _full_signature):
+    valid = (_access_key, _secret_key, _message, _full_signature)
+    len_valid = len(valid)
+
+    def _invalid(wrong_index):
+        args = list(valid)
+        arg = args.pop(wrong_index)
+        args.insert(wrong_index, arg + 'x')
+        return args
+
+    invalid = (_invalid(i) for i in range(len_valid - 1))
+
     assert verify_signature(*valid)
+
     for args in invalid:
         assert not verify_signature(*args)