Add additional coercion support for "self subtypes" to int, long,

float (compare the recent checkin to complex).  Added tests for these.

Lib/test/test_descr.py

@@ -1924,6 +1924,33 @@ def rich_comparisons():
                     verify(eval("x %s c[y]" % op) == eval("x %s y" % op),
                            "x=%d, y=%d" % (x, y))
 
+def coercions():
+    if verbose: print "Testing coercions..."
+    class I(int): pass
+    coerce(I(0), 0)
+    coerce(0, I(0))
+    class L(long): pass
+    coerce(L(0), 0)
+    coerce(L(0), 0L)
+    coerce(0, L(0))
+    coerce(0L, L(0))
+    class F(float): pass
+    coerce(F(0), 0)
+    coerce(F(0), 0L)
+    coerce(F(0), 0.)
+    coerce(0, F(0))
+    coerce(0L, F(0))
+    coerce(0., F(0))
+    class C(complex): pass
+    coerce(C(0), 0)
+    coerce(C(0), 0L)
+    coerce(C(0), 0.)
+    coerce(C(0), 0j)
+    coerce(0, C(0))
+    coerce(0L, C(0))
+    coerce(0., C(0))
+    coerce(0j, C(0))
+
 
 def all():
     lists()
@@ -1964,6 +1991,7 @@ def all():
     str_subclass_as_dict_key()
     classic_comparisons()
     rich_comparisons()
+    coercions()
 
 all()
 

Objects/floatobject.c

@@ -590,6 +590,11 @@ float_coerce(PyObject **pv, PyObject **pw)
 		Py_INCREF(*pv);
 		return 0;
 	}
+	else if (PyFloat_Check(*pw)) {
+		Py_INCREF(*pv);
+		Py_INCREF(*pw);
+		return 0;
+	}
 	return 1; /* Can't do it */
 }
 

Objects/intobject.c

@@ -782,6 +782,17 @@ int_or(PyIntObject *v, PyIntObject *w)
 	return PyInt_FromLong(a | b);
 }
 
+static int
+int_coerce(PyObject **pv, PyObject **pw)
+{
+	if (PyInt_Check(*pw)) {
+		Py_INCREF(*pv);
+		Py_INCREF(*pw);
+		return 0;
+	}
+	return 1; /* Can't do it */
+}
+
 static PyObject *
 int_int(PyIntObject *v)
 {
@@ -904,7 +915,7 @@ static PyNumberMethods int_as_number = {
 	(binaryfunc)int_and,	/*nb_and*/
 	(binaryfunc)int_xor,	/*nb_xor*/
 	(binaryfunc)int_or,	/*nb_or*/
-	0,			/*nb_coerce*/
+	int_coerce,		/*nb_coerce*/
 	(unaryfunc)int_int,	/*nb_int*/
 	(unaryfunc)int_long,	/*nb_long*/
 	(unaryfunc)int_float,	/*nb_float*/

Objects/longobject.c

@@ -2134,6 +2134,11 @@ long_coerce(PyObject **pv, PyObject **pw)
 		Py_INCREF(*pv);
 		return 0;
 	}
+	else if (PyLong_Check(*pw)) {
+		Py_INCREF(*pv);
+		Py_INCREF(*pw);
+		return 0;
+	}
 	return 1; /* Can't do it */
 }