Merged revisions 61038,61042-61045,61047,61050,61053,61055-61056,61061-61062,61066,61068,61070,61083,61085,61092-61103 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r61098 | jeffrey.yasskin | 2008-02-28 05:45:36 +0100 (Thu, 28 Feb 2008) | 7 lines

  Move abc._Abstract into object by adding a new flag Py_TPFLAGS_IS_ABSTRACT,
  which forbids constructing types that have it set. The effect is to speed

    ./python.exe -m timeit -s 'import abc' -s 'class Foo(object): __metaclass__ = abc.ABCMeta' 'Foo()'

  up from 2.5us to 0.201us. This fixes issue 1762.
........
  r61099 | jeffrey.yasskin | 2008-02-28 06:53:18 +0100 (Thu, 28 Feb 2008) | 3 lines

  Speed test_socketserver up from 28.739s to 0.226s, simplify the logic, and make
  sure all tests run even if some fail.
........
  r61100 | jeffrey.yasskin | 2008-02-28 07:09:19 +0100 (Thu, 28 Feb 2008) | 21 lines

  Thread.start() used sleep(0.000001) to make sure it didn't return before the
  new thread had started. At least on my MacBook Pro, that wound up sleeping for
  a full 10ms (probably 1 jiffy). By using an Event instead, we can be absolutely
  certain that the thread has started, and return more quickly (217us).

  Before:
  $  ./python.exe -m timeit -s 'from threading import Thread'  't = Thread(); t.start(); t.join()'
  100 loops, best of 3: 10.3 msec per loop
  $  ./python.exe -m timeit -s 'from threading import Thread; t = Thread()'  't.isAlive()'
  1000000 loops, best of 3: 0.47 usec per loop

  After:
  $  ./python.exe -m timeit -s 'from threading import Thread'  't = Thread(); t.start(); t.join()'
  1000 loops, best of 3: 217 usec per loop
  $  ./python.exe -m timeit -s 'from threading import Thread; t = Thread()'  't.isAlive()'
  1000000 loops, best of 3: 0.86 usec per loop

  To be fair, the 10ms isn't CPU time, and other threads including the spawned
  one get to run during it. There are also some slightly more complicated ways to
  get back the .4us in isAlive() if we want.
........
  r61101 | raymond.hettinger | 2008-02-28 10:23:48 +0100 (Thu, 28 Feb 2008) | 1 line

  Add repeat keyword argument to itertools.product().
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  r61102 | christian.heimes | 2008-02-28 12:18:49 +0100 (Thu, 28 Feb 2008) | 1 line

  The empty tuple is usually a singleton with a much higher refcnt than 1
........

1 files changed, 98 insertions, 0 deletions

diff --git a/Objects/typeobject.c b/Objects/typeobject.c
index 1d6336c..7a6d258 100644
--- a/Objects/typeobject.c
+++ b/Objects/typeobject.c
@@ -319,6 +319,40 @@ type_set_module(PyTypeObject *type, PyObject *value, void *context)
 }
 
 static PyObject *
+type_abstractmethods(PyTypeObject *type, void *context)
+{
+	PyObject *mod = PyDict_GetItemString(type->tp_dict,
+					     "__abstractmethods__");
+	if (!mod) {
+		PyErr_Format(PyExc_AttributeError, "__abstractmethods__");
+		return NULL;
+	}
+	Py_XINCREF(mod);
+	return mod;
+}
+
+static int
+type_set_abstractmethods(PyTypeObject *type, PyObject *value, void *context)
+{
+	/* __abstractmethods__ should only be set once on a type, in
+	   abc.ABCMeta.__new__, so this function doesn't do anything
+	   special to update subclasses.
+	*/
+	int res = PyDict_SetItemString(type->tp_dict,
+				       "__abstractmethods__", value);
+	if (res == 0) {
+		type_modified(type);
+		if (value && PyObject_IsTrue(value)) {
+			type->tp_flags |= Py_TPFLAGS_IS_ABSTRACT;
+		}
+		else {
+			type->tp_flags &= ~Py_TPFLAGS_IS_ABSTRACT;
+		}
+	}
+	return res;
+}
+
+static PyObject *
 type_get_bases(PyTypeObject *type, void *context)
 {
 	Py_INCREF(type->tp_bases);
@@ -555,6 +589,8 @@ static PyGetSetDef type_getsets[] = {
 	{"__name__", (getter)type_name, (setter)type_set_name, NULL},
 	{"__bases__", (getter)type_get_bases, (setter)type_set_bases, NULL},
 	{"__module__", (getter)type_module, (setter)type_set_module, NULL},
+	{"__abstractmethods__", (getter)type_abstractmethods,
+	 (setter)type_set_abstractmethods, NULL},
 	{"__dict__",  (getter)type_dict,  NULL, NULL},
 	{"__doc__", (getter)type_get_doc, NULL, NULL},
 	{0}
@@ -2638,6 +2674,52 @@ object_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 	}
 	if (err < 0)
 		return NULL;
+
+	if (type->tp_flags & Py_TPFLAGS_IS_ABSTRACT) {
+		static PyObject *comma = NULL;
+		PyObject *abstract_methods = NULL;
+		PyObject *builtins;
+		PyObject *sorted;
+		PyObject *sorted_methods = NULL;
+		PyObject *joined = NULL;
+
+		/* Compute ", ".join(sorted(type.__abstractmethods__))
+		   into joined. */
+		abstract_methods = type_abstractmethods(type, NULL);
+		if (abstract_methods == NULL)
+			goto error;
+		builtins = PyEval_GetBuiltins();
+		if (builtins == NULL)
+			goto error;
+		sorted = PyDict_GetItemString(builtins, "sorted");
+		if (sorted == NULL)
+			goto error;
+		sorted_methods = PyObject_CallFunctionObjArgs(sorted,
+							      abstract_methods,
+							      NULL);
+		if (sorted_methods == NULL)
+			goto error;
+		if (comma == NULL) {
+			comma = PyUnicode_InternFromString(", ");
+			if (comma == NULL)
+				goto error;
+		}
+		joined = PyObject_CallMethod(comma, "join",
+					     "O",  sorted_methods);
+		if (joined == NULL)
+			goto error;
+
+		PyErr_Format(PyExc_TypeError,
+			     "Can't instantiate abstract class %s "
+			     "with abstract methods %U",
+			     type->tp_name,
+			     joined);
+	error:
+		Py_XDECREF(joined);
+		Py_XDECREF(sorted_methods);
+		Py_XDECREF(abstract_methods);
+		return NULL;
+	}
 	return type->tp_alloc(type, 0);
 }
 
@@ -3143,6 +3225,20 @@ object_reduce_ex(PyObject *self, PyObject *args)
 	return _common_reduce(self, proto);
 }
 
+static PyObject *
+object_subclasshook(PyObject *cls, PyObject *args)
+{
+	Py_INCREF(Py_NotImplemented);
+	return Py_NotImplemented;
+}
+
+PyDoc_STRVAR(object_subclasshook_doc,
+"Abstract classes can override this to customize issubclass().\n"
+"\n"
+"This is invoked early on by abc.ABCMeta.__subclasscheck__().\n"
+"It should return True, False or NotImplemented.  If it returns\n"
+"NotImplemented, the normal algorithm is used.  Otherwise, it\n"
+"overrides the normal algorithm (and the outcome is cached).\n");
 
 /*
    from PEP 3101, this code implements:
@@ -3183,6 +3279,8 @@ static PyMethodDef object_methods[] = {
 	 PyDoc_STR("helper for pickle")},
 	{"__reduce__", object_reduce, METH_VARARGS,
 	 PyDoc_STR("helper for pickle")},
+	{"__subclasshook__", object_subclasshook, METH_CLASS | METH_VARARGS,
+	 object_subclasshook_doc},
         {"__format__", object_format, METH_VARARGS,
          PyDoc_STR("default object formatter")},
 	{0}