Remove dependency to case

requirements/test.txt

@@ -1,4 +1,3 @@
-case>=1.3.1
 pytest>=3.0,<=5.3.5
 pytest-sugar>=0.9.1
 pytest-rerunfailures>=6.0

t/mocks.py

@@ -0,0 +1,24 @@
+from unittest.mock import Mock
+
+class _ContextMock(Mock):
+    """Dummy class implementing __enter__ and __exit__
+    as the :keyword:`with` statement requires these to be implemented
+    in the class, not just the instance."""
+
+    def __enter__(self):
+        return self
+
+    def __exit__(self, *exc_info):
+        pass
+
+
+def ContextMock(*args, **kwargs):
+    """Mock that mocks :keyword:`with` statement contexts."""
+    obj = _ContextMock(*args, **kwargs)
+    obj.attach_mock(_ContextMock(), '__enter__')
+    obj.attach_mock(_ContextMock(), '__exit__')
+    obj.__enter__.return_value = obj
+    # if __exit__ return a value the exception is ignored,
+    # so it must return None here.
+    obj.__exit__.return_value = None
+    return obj

t/unit/conftest.py

@@ -0,0 +1,78 @@
+from unittest.mock import MagicMock
+import pytest
+
+sentinel = object()
+
+class _patching(object):
+
+    def __init__(self, monkeypatch, request):
+        self.monkeypatch = monkeypatch
+        self.request = request
+
+    def __getattr__(self, name):
+        return getattr(self.monkeypatch, name)
+
+    def __call__(self, path, value=sentinel, name=None,
+                 new=MagicMock, **kwargs):
+        value = self._value_or_mock(value, new, name, path, **kwargs)
+        self.monkeypatch.setattr(path, value)
+        return value
+
+    def object(self, target, attribute, *args, **kwargs):
+        return _wrap_context(
+            patch.object(target, attribute, *args, **kwargs),
+            self.request)
+
+    def _value_or_mock(self, value, new, name, path, **kwargs):
+        if value is sentinel:
+            value = new(name=name or path.rpartition('.')[2])
+        for k, v in kwargs.items():
+            setattr(value, k, v)
+        return value
+
+    def setattr(self, target, name=sentinel, value=sentinel, **kwargs):
+        # alias to __call__ with the interface of pytest.monkeypatch.setattr
+        if value is sentinel:
+            value, name = name, None
+        return self(target, value, name=name)
+
+    def setitem(self, dic, name, value=sentinel, new=MagicMock, **kwargs):
+        # same as pytest.monkeypatch.setattr but default value is MagicMock
+        value = self._value_or_mock(value, new, name, dic, **kwargs)
+        self.monkeypatch.setitem(dic, name, value)
+        return value
+
+    def modules(self, *mods):
+        modules = []
+        for mod in mods:
+            mod = mod.split('.')
+            modules.extend(reversed([
+                '.'.join(mod[:-i] if i else mod) for i in range(len(mod))
+            ]))
+        modules = sorted(set(modules))
+        return _wrap_context(mock.module(*modules), self.request)
+
+
+def _wrap_context(context, request):
+    ret = context.__enter__()
+
+    def fin():
+        context.__exit__(*sys.exc_info())
+    request.addfinalizer(fin)
+    return ret
+
+
+@pytest.fixture()
+def patching(monkeypatch, request):
+    """Monkeypath.setattr shortcut.
+    Example:
+        .. code-block:: python
+        def test_foo(patching):
+            # execv value here will be mock.MagicMock by default.
+            execv = patching('os.execv')
+            patching('sys.platform', 'darwin')  # set concrete value
+            patching.setenv('DJANGO_SETTINGS_MODULE', 'x.settings')
+            # val will be of type mock.MagicMock by default
+            val = patching.setitem('path.to.dict', 'KEY')
+    """
+    return _patching(monkeypatch, request)

t/unit/test_channel.py

@@ -3,7 +3,6 @@
 from unittest.mock import ANY, MagicMock, Mock, patch
 
 import pytest
-from case import ContextMock
 from vine import promise
 
 from amqp import spec
@@ -13,6 +12,7 @@
                              RecoverableConnectionError)
 from amqp.serialization import dumps
 
+from t.mocks import ContextMock
 
 class test_Channel:
 

t/unit/test_connection.py

@@ -4,7 +4,6 @@
 from unittest.mock import Mock, call, patch
 
 import pytest
-from case import ContextMock
 
 from amqp import Connection, spec
 from amqp.connection import SSLError
@@ -13,6 +12,8 @@
 from amqp.sasl import AMQPLAIN, EXTERNAL, GSSAPI, PLAIN, SASL
 from amqp.transport import TCPTransport
 
+from t.mocks import ContextMock
+
 
 class test_Connection: