[config] Implements "Exclusive" context processor allowing to ask for an exclusive usage of a service while in a transformation.

tests/config/test_methods.py

@@ -0,0 +1,82 @@
+import pytest
+
+from bonobo.config import Configurable, Method, Option
+from bonobo.errors import ConfigurationError
+
+
+class MethodBasedConfigurable(Configurable):
+    handler = Method()
+    foo = Option(positional=True)
+    bar = Option()
+
+    def call(self, *args, **kwargs):
+        self.handler(*args, **kwargs)
+
+
+def test_one_wrapper_only():
+    with pytest.raises(ConfigurationError):
+
+        class TwoMethods(Configurable):
+            h1 = Method()
+            h2 = Method()
+
+
+def test_define_with_decorator():
+    calls = []
+
+    @MethodBasedConfigurable
+    def Concrete(self, *args, **kwargs):
+        calls.append((args, kwargs, ))
+
+    assert callable(Concrete.handler)
+    t = Concrete('foo', bar='baz')
+
+    assert callable(t.handler)
+    assert len(calls) == 0
+    t()
+    assert len(calls) == 1
+
+
+def test_define_with_argument():
+    calls = []
+
+    def concrete_handler(*args, **kwargs):
+        calls.append((args, kwargs, ))
+
+    t = MethodBasedConfigurable('foo', bar='baz', handler=concrete_handler)
+    assert callable(t.handler)
+    assert len(calls) == 0
+    t()
+    assert len(calls) == 1
+
+
+def test_define_with_inheritance():
+    calls = []
+
+    class Inheriting(MethodBasedConfigurable):
+        def handler(self, *args, **kwargs):
+            calls.append((args, kwargs, ))
+
+    t = Inheriting('foo', bar='baz')
+    assert callable(t.handler)
+    assert len(calls) == 0
+    t()
+    assert len(calls) == 1
+
+
+def test_inheritance_then_decorate():
+    calls = []
+
+    class Inheriting(MethodBasedConfigurable):
+        pass
+
+    @Inheriting
+    def Concrete(self, *args, **kwargs):
+        calls.append((args, kwargs, ))
+
+    assert callable(Concrete.handler)
+    t = Concrete('foo', bar='baz')
+    assert callable(t.handler)
+    assert len(calls) == 0
+    t()
+    assert len(calls) == 1