Merge 2b058db into 1ded4d9

.travis.yml

@@ -9,12 +9,12 @@ matrix:
     include:
         - name: "2.7-pure"
           python: "2.7"
-          env: PURE_PYTHON = 1
+          env: PURE_PYTHON=1
         - python: "3.7"
           dist: xenial
         - name: "3.7-pure"
           python: "3.7"
-          env: PURE_PYTHON = 1
+          env: PURE_PYTHON=1
           dist: xenial
         - python: "3.8-dev"
           dist: xenial

CHANGES.rst

@@ -8,6 +8,10 @@ Changelog
 
 - Add support for Python 3.8a3.
 
+- Add support to call ``bytes()`` on an object wrapped by an
+  ``ImplicitAcquisitionWrapper``.
+  (`#38 <https://github.com/zopefoundation/Acquisition/issues/38>`_)
+
 
 4.5 (2018-10-05)
 ----------------

README.rst

@@ -429,7 +429,7 @@ Conclusion
 ----------
 
 Acquisition provides a powerful way to dynamically share information
-between objects. Zope 2 uses acquisition for a number of its key
+between objects. Zope uses acquisition for a number of its key
 features including security, object publishing, and DTML variable
 lookup. Acquisition also provides an elegant solution to the problem
 of circular references for many classes of problems. While acquisition

src/Acquisition/_Acquisition.c

@@ -46,7 +46,8 @@ static PyObject *py__add__, *py__sub__, *py__mul__, *py__div__,
   *py__long__, *py__float__, *py__oct__, *py__hex__,
   *py__getitem__, *py__setitem__, *py__delitem__,
   *py__getslice__, *py__setslice__, *py__delslice__,  *py__contains__,
-  *py__len__, *py__of__, *py__call__, *py__repr__, *py__str__, *py__unicode__,
+  *py__len__, *py__of__, *py__call__, *py__repr__,
+  *py__str__, *py__unicode__, *py__bytes__,
   *py__cmp__, *py__parent__, *py__iter__, *py__bool__, *py__index__, *py__iadd__,
   *py__isub__, *py__imul__, *py__imod__, *py__ipow__, *py__ilshift__, *py__irshift__,
   *py__iand__, *py__ixor__, *py__ior__, *py__floordiv__, *py__truediv__,
@@ -95,6 +96,7 @@ init_py_names(void)
   INIT_PY_NAME(__repr__);
   INIT_PY_NAME(__str__);
   INIT_PY_NAME(__unicode__);
+  INIT_PY_NAME(__bytes__);
   INIT_PY_NAME(__cmp__);
   INIT_PY_NAME(__parent__);
   INIT_PY_NAME(__iter__);
@@ -970,6 +972,24 @@ Wrapper_unicode(Wrapper *self)
     }
 }
 
+static PyObject *
+Wrapper_bytes(Wrapper *self)
+{
+    PyObject *r;
+
+    if ((r = PyObject_GetAttr(OBJECT(self), py__bytes__))) {
+        ASSIGN(r, PyObject_CallFunction(r, NULL, NULL));
+        return r;
+    } else {
+        PyErr_Clear();
+#ifdef PY3K
+        return PyBytes_FromObject(self->obj);
+#else
+        return Wrapper_str(self);
+#endif
+    }
+}
+
 static long
 Wrapper_hash(Wrapper *self)
 {
@@ -1487,6 +1507,8 @@ static struct PyMethodDef Wrapper_methods[] = {
    "Wrappers are not picklable"},
   {"__unicode__", (PyCFunction)Wrapper_unicode, METH_NOARGS,
    "Unicode"},
+  {"__bytes__", (PyCFunction)Wrapper_bytes, METH_NOARGS,
+   "Bytes"},
   {NULL,  NULL}
 };
 

src/Acquisition/__init__.py

@@ -47,7 +47,7 @@ def _apply_filter(predicate, inst, name, result, extra, orig):
     return predicate(orig, inst, name, result, extra)
 
 
-if sys.version_info < (3,):
+if sys.version_info < (3,):  # pragma: PY2
     import copy_reg
 
     def _rebound_method(method, wrapper):
@@ -566,6 +566,13 @@ def __str__(self):
         except (AttributeError, TypeError):  # pragma: PY3
             return str(aq_self)
 
+    def __bytes__(self):
+        aq_self = self._obj
+        try:
+            return _rebound_method(aq_self.__bytes__, self)()
+        except (AttributeError, TypeError):  # pragma: PY3
+            return bytes(aq_self)
+
     __binary_special_methods__ = [
         # general numeric
         '__add__',

src/Acquisition/tests.py

@@ -2449,6 +2449,27 @@ class Impl(Implicit):
         # By the time it gets there, it's not wrapped:
         self.assertIs(type(child.__dict__['child2']), Impl)
 
+    def test__bytes__is_correcty_wrapped(self):
+        class A(Implicit):
+
+            def __bytes__(self):
+                return b'my bytes'
+
+        a = A()
+        a.b = A()
+        wrapper = Acquisition.ImplicitAcquisitionWrapper(a.b, a)
+        self.assertEqual(b'my bytes', bytes(wrapper))
+
+    def test_AttributeError_if_object_has_no__bytes__(self):
+        class A(Implicit):
+            pass
+
+        a = A()
+        a.b = A()
+        wrapper = Acquisition.ImplicitAcquisitionWrapper(a.b, a)
+        with self.assertRaises(TypeError):
+            bytes(wrapper)
+
 
 class TestOf(unittest.TestCase):