Change ValueError to io.UnsupportedOperation in capture.py. Resolves issue #2276

_pytest/capture.py

@@ -13,6 +13,7 @@ import py
 import pytest
 
 from py.io import TextIO
+from io import UnsupportedOperation
 unicode = py.builtin.text
 
 patchsysdict = {0: 'stdin', 1: 'stdout', 2: 'stderr'}
@@ -448,7 +449,7 @@ class DontReadFromInput:
     __iter__ = read
 
     def fileno(self):
-        raise ValueError("redirected Stdin is pseudofile, has no fileno()")
+        raise UnsupportedOperation("redirected Stdin is pseudofile, has no fileno()")
 
     def isatty(self):
         return False

testing/test_capture.py

@@ -4,6 +4,7 @@ from __future__ import with_statement
 import pickle
 import os
 import sys
+from io import UnsupportedOperation
 
 import _pytest._code
 import py
@@ -658,7 +659,7 @@ def test_dontreadfrominput():
     pytest.raises(IOError, f.read)
     pytest.raises(IOError, f.readlines)
     pytest.raises(IOError, iter, f)
-    pytest.raises(ValueError, f.fileno)
+    pytest.raises(UnsupportedOperation, f.fileno)
     f.close()  # just for completeness