Catch both IOError and OSError, fix regression introduced by 8046f0a070a6

hgext/mq.py

@@ -1583,7 +1583,7 b' class queue:'
                         text = sys.stdin.read()
                     else:
                         text = url.open(self.ui, filename).read()
-                except IOError:
+                except (OSError, IOError):
                     raise util.Abort(_("unable to read %s") % filename)
                 if not patchname:
                     patchname = normname(os.path.basename(filename))

tests/test-mq-qimport

@@ -25,7 +25,7 b' hg init repo'
 cd repo
 
 echo % qimport non-existing-file
-hg qimport non-existing-file 2>&1 | sed -e 's/\(No such file or directory:\) .*/\1/'
+hg qimport non-existing-file
 
 echo % import URL
 echo foo >> foo

tests/test-mq-qimport.out

@@ -1,5 +1,5 b''
 % qimport non-existing-file
-abort: No such file or directory:
+abort: unable to read non-existing-file
 % import URL
 adding url.diff to series file
 url.diff