Close SF bug 563740. complex() now finds __complex__() in new style classes.

Made conversion failure error messages consistent between types.
Added related unittests.

Lib/test/test_b1.py

@@ -101,6 +101,17 @@ print 'compile'
 compile('print 1\n', '', 'exec')
 
 print 'complex'
+class OS:
+   def __complex__(self): return 1+10j
+class NS(object):
+   def __complex__(self): return 1+10j
+if complex(OS()) != 1+10j: raise TestFailed, '__complex__ in old style class'
+if complex(NS()) != 1+10j: raise TestFailed, '__complex__ in new style class'
+if complex("1+10j") != 1+10j: raise TestFailed, 'complex("1+10j")'
+if complex(10) != 10+0j: raise TestFailed, 'complex(10)'
+if complex(10.0) != 10+0j: raise TestFailed, 'complex(10.0)'
+if complex(10L) != 10+0j: raise TestFailed, 'complex(10L)'
+if complex(10+0j) != 10+0j: raise TestFailed, 'complex(10+0j)'
 if complex(1,10) != 1+10j: raise TestFailed, 'complex(1,10)'
 if complex(1,10L) != 1+10j: raise TestFailed, 'complex(1,10L)'
 if complex(1,10.0) != 1+10j: raise TestFailed, 'complex(1,10.0)'

Objects/abstract.c

@@ -903,7 +903,7 @@ PyNumber_Int(PyObject *o)
 	if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
 		return int_from_string((char*)buffer, buffer_len);
 
-	return type_error("object can't be converted to int");
+	return type_error("int() argument must be a string or a number");
 }
 
 /* Add a check for embedded NULL-bytes in the argument. */
@@ -960,7 +960,7 @@ PyNumber_Long(PyObject *o)
 	if (!PyObject_AsCharBuffer(o, &buffer, &buffer_len))
 		return long_from_string(buffer, buffer_len);
 
-	return type_error("object can't be converted to long");
+	return type_error("long() argument must be a string or a number");
 }
 
 PyObject *

Objects/complexobject.c

@@ -811,10 +811,11 @@ complex_subtype_from_string(PyTypeObject *type, PyObject *v)
 static PyObject *
 complex_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
-	PyObject *r, *i, *tmp;
+	PyObject *r, *i, *tmp, *f;
 	PyNumberMethods *nbr, *nbi = NULL;
 	Py_complex cr, ci;
 	int own_r = 0;
+	static PyObject *complexstr;
 	static char *kwlist[] = {"real", "imag", 0};
 
 	r = Py_False;
@@ -837,39 +838,35 @@ complex_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 		return NULL;
 	}
 
+	/* XXX Hack to support classes with __complex__ method */
+	if (complexstr == NULL) {
+		complexstr = PyString_InternFromString("__complex__");
+		if (complexstr == NULL)
+			return NULL;
+	}
+	f = PyObject_GetAttr(r, complexstr);
+	if (f == NULL)
+		PyErr_Clear();
+	else {
+		PyObject *args = Py_BuildValue("()");
+		if (args == NULL)
+			return NULL;
+		r = PyEval_CallObject(f, args);
+		Py_DECREF(args);
+		Py_DECREF(f);
+		if (r == NULL)
+			return NULL;
+		own_r = 1;
+	}
 	nbr = r->ob_type->tp_as_number;
 	if (i != NULL)
 		nbi = i->ob_type->tp_as_number;
 	if (nbr == NULL || nbr->nb_float == NULL ||
 	    ((i != NULL) && (nbi == NULL || nbi->nb_float == NULL))) {
 		PyErr_SetString(PyExc_TypeError,
-			   "complex() arg can't be converted to complex");
+			   "complex() argument must be a string or a number");
 		return NULL;
 	}
-	/* XXX Hack to support classes with __complex__ method */
-	if (PyInstance_Check(r)) {
-		static PyObject *complexstr;
-		PyObject *f;
-		if (complexstr == NULL) {
-			complexstr = PyString_InternFromString("__complex__");
-			if (complexstr == NULL)
-				return NULL;
-		}
-		f = PyObject_GetAttr(r, complexstr);
-		if (f == NULL)
-			PyErr_Clear();
-		else {
-			PyObject *args = Py_BuildValue("()");
-			if (args == NULL)
-				return NULL;
-			r = PyEval_CallObject(f, args);
-			Py_DECREF(args);
-			Py_DECREF(f);
-			if (r == NULL)
-				return NULL;
-			own_r = 1;
-		}
-	}
 	if (PyComplex_Check(r)) {
 		/* Note that if r is of a complex subtype, we're only
 		   retaining its real & imag parts here, and the return