Merge pull request #202 from zopefoundation/issue3

Let interfaces override __adapt__

3 files changed, 216 insertions, 52 deletions

diff --git a/src/zope/interface/tests/test_adapter.py b/src/zope/interface/tests/test_adapter.py
index 869df66..8ff96f0 100644
--- a/src/zope/interface/tests/test_adapter.py
+++ b/src/zope/interface/tests/test_adapter.py
@@ -796,12 +796,12 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface import Interface
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         alb = self._makeOne(registry)
         self.assertEqual(sorted(alb._extendors.keys()),
                          sorted([IBar, IFoo, Interface]))
-        self.assertEqual(alb._extendors[IFoo], [IFoo])
+        self.assertEqual(alb._extendors[IFoo], [IFoo, IBar])
         self.assertEqual(alb._extendors[IBar], [IBar])
         self.assertEqual(sorted(alb._extendors[Interface]),
                          sorted([IFoo, IBar]))
@@ -847,14 +847,14 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface import Interface
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         alb = self._makeOne(registry)
         registry._provided = [IFoo, IBar]
         alb.init_extendors()
         self.assertEqual(sorted(alb._extendors.keys()),
                          sorted([IBar, IFoo, Interface]))
-        self.assertEqual(alb._extendors[IFoo], [IFoo])
+        self.assertEqual(alb._extendors[IFoo], [IFoo, IBar])
         self.assertEqual(alb._extendors[IBar], [IBar])
         self.assertEqual(sorted(alb._extendors[Interface]),
                          sorted([IFoo, IBar]))
@@ -863,14 +863,14 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface import Interface
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         alb = self._makeOne(registry)
         alb.add_extendor(IFoo)
         alb.add_extendor(IBar)
         self.assertEqual(sorted(alb._extendors.keys()),
                          sorted([IBar, IFoo, Interface]))
-        self.assertEqual(alb._extendors[IFoo], [IFoo])
+        self.assertEqual(alb._extendors[IFoo], [IFoo, IBar])
         self.assertEqual(alb._extendors[IBar], [IBar])
         self.assertEqual(sorted(alb._extendors[Interface]),
                          sorted([IFoo, IBar]))
@@ -879,13 +879,13 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface import Interface
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         alb = self._makeOne(registry)
         alb.remove_extendor(IFoo)
         self.assertEqual(sorted(alb._extendors.keys()),
                          sorted([IFoo, IBar, Interface]))
-        self.assertEqual(alb._extendors[IFoo], [])
+        self.assertEqual(alb._extendors[IFoo], [IBar])
         self.assertEqual(alb._extendors[IBar], [IBar])
         self.assertEqual(sorted(alb._extendors[Interface]),
                          sorted([IBar]))
@@ -895,7 +895,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_empty_ro(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         alb = self._makeOne(registry)
         result = alb._uncached_lookup((IFoo,), IBar)
@@ -906,7 +906,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_order_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         registry.ro.append(subr)
@@ -917,7 +917,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_extendors_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         subr = self._makeSubregistry()
         subr._adapters = [{}, {}] #utilities, single adapters
@@ -930,7 +930,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_components_miss_wrong_iface(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         IQux = InterfaceClass('IQux')
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
@@ -949,7 +949,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_components_miss_wrong_name(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
 
@@ -968,7 +968,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_simple_hit(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         _expected = object()
@@ -985,7 +985,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookup_repeated_hit(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         _expected = object()
@@ -1005,7 +1005,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface.declarations import implementer
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         @implementer(IFoo)
         class Foo(object):
             pass
@@ -1051,7 +1051,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface.declarations import implementer
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         @implementer(IFoo)
         class Foo(object):
             pass
@@ -1080,7 +1080,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface.declarations import implementer
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         @implementer(IFoo)
         class Foo(object):
             pass
@@ -1131,7 +1131,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookupAll_empty_ro(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         alb = self._makeOne(registry)
         result = alb._uncached_lookupAll((IFoo,), IBar)
@@ -1142,7 +1142,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookupAll_order_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         registry.ro.append(subr)
@@ -1154,7 +1154,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookupAll_extendors_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         subr = self._makeSubregistry()
         subr._adapters = [{}, {}] #utilities, single adapters
@@ -1167,7 +1167,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookupAll_components_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         IQux = InterfaceClass('IQux')
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
@@ -1185,7 +1185,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_lookupAll_simple_hit(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         _expected = object()
@@ -1203,7 +1203,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test_names(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         _expected = object()
@@ -1222,7 +1222,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_empty_ro(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         alb = self._makeOne(registry)
         result = alb._uncached_subscriptions((IFoo,), IBar)
@@ -1233,7 +1233,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_order_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         registry.ro.append(subr)
@@ -1245,7 +1245,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_extendors_miss(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry()
         subr = self._makeSubregistry()
         subr._subscribers = [{}, {}] #utilities, single adapters
@@ -1258,7 +1258,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_components_miss_wrong_iface(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         IQux = InterfaceClass('IQux')
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
@@ -1276,7 +1276,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_components_miss_wrong_name(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         wrongname = object()
@@ -1293,7 +1293,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
     def test__uncached_subscriptions_simple_hit(self):
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         registry = self._makeRegistry(IFoo, IBar)
         subr = self._makeSubregistry()
         class Foo(object):
@@ -1314,7 +1314,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface.declarations import implementer
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         @implementer(IFoo)
         class Foo(object):
             pass
@@ -1343,7 +1343,7 @@ class AdapterLookupBaseTests(unittest.TestCase):
         from zope.interface.declarations import implementer
         from zope.interface.interface import InterfaceClass
         IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar', IFoo)
+        IBar = InterfaceClass('IBar', (IFoo,))
         @implementer(IFoo)
         class Foo(object):
             pass
diff --git a/src/zope/interface/tests/test_declarations.py b/src/zope/interface/tests/test_declarations.py
index 5d7272a..83815d7 100644
--- a/src/zope/interface/tests/test_declarations.py
+++ b/src/zope/interface/tests/test_declarations.py
@@ -864,25 +864,30 @@ class Test_classImplements(unittest.TestCase):
     def test_w_existing_Implements_w_bases(self):
         from zope.interface.declarations import Implements
         from zope.interface.interface import InterfaceClass
-        IFoo = InterfaceClass('IFoo')
-        IBar = InterfaceClass('IBar')
-        IBaz = InterfaceClass('IBaz', IFoo)
-        b_impl = Implements(IBaz)
-        impl = Implements(IFoo)
-        impl.declared = (IFoo,)
-        class Base1(object):
-            __implemented__ = b_impl
-        class Base2(object):
-            __implemented__ = b_impl
-        class Foo(Base1, Base2):
-            __implemented__ = impl
-        impl.inherit = Foo
-        self._callFUT(Foo, IBar)
+        IRoot = InterfaceClass('IRoot')
+        ISecondRoot = InterfaceClass('ISecondRoot')
+        IExtendsRoot = InterfaceClass('IExtendsRoot', (IRoot,))
+
+        impl_root = Implements.named('Root', IRoot)
+        impl_root.declared = (IRoot,)
+
+        class Root1(object):
+            __implemented__ = impl_root
+        class Root2(object):
+            __implemented__ = impl_root
+
+        impl_extends_root = Implements.named('ExtendsRoot1', IExtendsRoot)
+        impl_extends_root.declared = (IExtendsRoot,)
+        class ExtendsRoot(Root1, Root2):
+            __implemented__ = impl_extends_root
+        impl_extends_root.inherit = ExtendsRoot
+
+        self._callFUT(ExtendsRoot, ISecondRoot)
         # Same spec, now different values
-        self.assertTrue(Foo.__implemented__ is impl)
-        self.assertEqual(impl.inherit, Foo)
-        self.assertEqual(impl.declared, (IFoo, IBar,))
-        self.assertEqual(impl.__bases__, (IFoo, IBar, b_impl))
+        self.assertIs(ExtendsRoot.__implemented__, impl_extends_root)
+        self.assertEqual(impl_extends_root.inherit, ExtendsRoot)
+        self.assertEqual(impl_extends_root.declared, (IExtendsRoot, ISecondRoot,))
+        self.assertEqual(impl_extends_root.__bases__, (IExtendsRoot, ISecondRoot, impl_root))
 
 
 class Test__implements_advice(unittest.TestCase):
diff --git a/src/zope/interface/tests/test_interface.py b/src/zope/interface/tests/test_interface.py
index 2100340..036e858 100644
--- a/src/zope/interface/tests/test_interface.py
+++ b/src/zope/interface/tests/test_interface.py
@@ -1318,9 +1318,9 @@ class InterfaceTests(unittest.TestCase):
 
         new = Interface.__class__
         FunInterface = new('FunInterface')
-        BarInterface = new('BarInterface', [FunInterface])
+        BarInterface = new('BarInterface', (FunInterface,))
         BobInterface = new('BobInterface')
-        BazInterface = new('BazInterface', [BobInterface, BarInterface])
+        BazInterface = new('BazInterface', (BobInterface, BarInterface,))
 
         self.assertTrue(BazInterface.extends(BobInterface))
         self.assertTrue(BazInterface.extends(BarInterface))
@@ -2161,6 +2161,165 @@ class InterfaceTests(unittest.TestCase):
         finally:
             adapter_hooks[:] = old_adapter_hooks
 
+    def test___call___w_overridden_adapt(self):
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+        from zope.interface import implementer
+
+        class I(Interface):
+
+            @interfacemethod
+            def __adapt__(self, obj):
+                return 42
+
+        @implementer(I)
+        class O(object):
+            pass
+
+        self.assertEqual(42, I(object()))
+        # __adapt__ can ignore the fact that the object provides
+        # the interface if it chooses.
+        self.assertEqual(42, I(O()))
+
+    def test___call___w_overridden_adapt_and_conform(self):
+        # Conform is first, taking precedence over __adapt__,
+        # *if* it returns non-None
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+        from zope.interface import implementer
+
+        class IAdapt(Interface):
+            @interfacemethod
+            def __adapt__(self, obj):
+                return 42
+
+        class ISimple(Interface):
+            """Nothing special."""
+
+        @implementer(IAdapt)
+        class Conform24(object):
+            def __conform__(self, iface):
+                return 24
+
+        @implementer(IAdapt)
+        class ConformNone(object):
+            def __conform__(self, iface):
+                return None
+
+        self.assertEqual(42, IAdapt(object()))
+
+        self.assertEqual(24, ISimple(Conform24()))
+        self.assertEqual(24, IAdapt(Conform24()))
+
+        with self.assertRaises(TypeError):
+            ISimple(ConformNone())
+
+        self.assertEqual(42, IAdapt(ConformNone()))
+
+
+    def test___call___w_overridden_adapt_call_super(self):
+        import sys
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+        from zope.interface import implementer
+
+        class I(Interface):
+
+            @interfacemethod
+            def __adapt__(self, obj):
+                if not self.providedBy(obj):
+                    return 42
+                if sys.version_info[:2] > (3, 5):
+                    # Python 3.5 raises 'RuntimeError: super() __class__ is not a type'
+                    return super().__adapt__(obj)
+
+                return super(type(I), self).__adapt__(obj)
+
+        @implementer(I)
+        class O(object):
+            pass
+
+        self.assertEqual(42, I(object()))
+        o = O()
+        self.assertIs(o, I(o))
+
+    def test___adapt___as_method_and_implementation(self):
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+
+        class I(Interface):
+            @interfacemethod
+            def __adapt__(self, obj):
+                return 42
+
+            def __adapt__(to_adapt):
+                "This is a protocol"
+
+        self.assertEqual(42, I(object()))
+        self.assertEqual(I['__adapt__'].getSignatureString(), '(to_adapt)')
+
+    def test___adapt__inheritance_and_type(self):
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+
+        class IRoot(Interface):
+            """Root"""
+
+        class IWithAdapt(IRoot):
+            @interfacemethod
+            def __adapt__(self, obj):
+                return 42
+
+        class IOther(IRoot):
+            """Second branch"""
+
+        class IUnrelated(Interface):
+            """Unrelated"""
+
+        class IDerivedAdapt(IUnrelated, IWithAdapt, IOther):
+            """Inherits an adapt"""
+            # Order of "inheritance" matters here.
+
+        class IDerived2Adapt(IDerivedAdapt):
+            """Overrides an inherited custom adapt."""
+            @interfacemethod
+            def __adapt__(self, obj):
+                return 24
+
+        self.assertEqual(42, IDerivedAdapt(object()))
+        for iface in IRoot, IWithAdapt, IOther, IUnrelated, IDerivedAdapt:
+            self.assertEqual(__name__, iface.__module__)
+
+        for iface in IRoot, IOther, IUnrelated:
+            self.assertEqual(type(IRoot), type(Interface))
+
+        # But things that implemented __adapt__ got a new type
+        self.assertNotEqual(type(Interface), type(IWithAdapt))
+        self.assertEqual(type(IWithAdapt), type(IDerivedAdapt))
+        self.assertIsInstance(IWithAdapt, type(Interface))
+
+        self.assertEqual(24, IDerived2Adapt(object()))
+        self.assertNotEqual(type(IDerived2Adapt), type(IDerivedAdapt))
+        self.assertIsInstance(IDerived2Adapt, type(IDerivedAdapt))
+
+    def test_interfacemethod_is_general(self):
+        from zope.interface import Interface
+        from zope.interface import interfacemethod
+
+        class I(Interface):
+
+            @interfacemethod
+            def __call__(self, obj):
+                """Replace an existing method"""
+                return 42
+
+            @interfacemethod
+            def this_is_new(self):
+                return 42
+
+        self.assertEqual(I(self), 42)
+        self.assertEqual(I.this_is_new(), 42)
+
 
 class AttributeTests(ElementTests):