[pypy-svn] pypy default: Negative values can be raised to the nan power.

[alex_gaynor]

Author: Alex Gaynor <alex.gaynor at gmail.com>
Branch: 
Changeset: r41526:57363f9b7479
Date: 2011-02-01 09:59 -0500
http://bitbucket.org/pypy/pypy/changeset/57363f9b7479/

Log:	Negative values can be raised to the nan power.

diff --git a/pypy/objspace/std/floatobject.py b/pypy/objspace/std/floatobject.py
--- a/pypy/objspace/std/floatobject.py
+++ b/pypy/objspace/std/floatobject.py
@@ -10,12 +10,13 @@
 from pypy.objspace.std.longobject import W_LongObject
 from pypy.rlib.rarithmetic import ovfcheck_float_to_int, intmask, isinf, isnan
 from pypy.rlib.rarithmetic import (LONG_BIT, INFINITY, copysign,
-    formatd, DTSF_ADD_DOT_0, DTSF_STR_PRECISION)
+    formatd, DTSF_ADD_DOT_0, DTSF_STR_PRECISION, NAN)
 from pypy.rlib.rbigint import rbigint
 from pypy.rlib.objectmodel import we_are_translated
 from pypy.rlib import rfloat
 from pypy.tool.sourcetools import func_with_new_name
 
+
 import math
 from pypy.objspace.std.intobject import W_IntObject
 
@@ -340,7 +341,7 @@
     x = w_float1.floatval
     y = w_float2.floatval
     if y == 0.0:
-        raise FailedToImplementArgs(space.w_ZeroDivisionError, space.wrap("float division"))    
+        raise FailedToImplementArgs(space.w_ZeroDivisionError, space.wrap("float division"))
     return W_FloatObject(x / y)
 
 truediv__Float_Float = div__Float_Float
@@ -424,6 +425,8 @@
     # unlike "math.pow(-1.0, bignum)".  See http://mail.python.org/
     # -           pipermail/python-bugs-list/2003-March/016795.html
     if x < 0.0:
+        if math.isnan(y):
+            return W_FloatObject(NAN)
         if math.floor(y) != y:
             raise OperationError(space.w_ValueError,
                                  space.wrap("negative number cannot be "

diff --git a/pypy/objspace/std/test/test_floatobject.py b/pypy/objspace/std/test/test_floatobject.py
--- a/pypy/objspace/std/test/test_floatobject.py
+++ b/pypy/objspace/std/test/test_floatobject.py
@@ -170,21 +170,23 @@
 
     def test_special_float_method(self):
         class a(object):
-            def __float__(self): 
-                self.ar = True 
+            def __float__(self):
+                self.ar = True
                 return None
         inst = a()
-        raises(TypeError, float, inst) 
-        assert inst.ar 
+        raises(TypeError, float, inst)
+        assert inst.ar
 
-        class b(object): 
-            pass 
-        raises((AttributeError, TypeError), float, b()) 
+        class b(object):
+            pass
+        raises((AttributeError, TypeError), float, b())
 
     def test_getnewargs(self):
         assert  0.0 .__getnewargs__() == (0.0,)
 
     def test_pow(self):
+        import math
+
         def pw(x, y):
             return x ** y
         def espeq(x, y):
@@ -200,6 +202,8 @@
         assert pw(-1.0, 1e200) == 1.0
         if self.py26:
             assert pw(0.0, float("-inf")) == float("inf")
+            assert math.isnan(pw(-3, float("nan")))
+            assert math.isnan(pw(-3., float("nan")))
 
     def test_pow_neg_base(self):
         import math