Merged revisions 76805 via svnmerge from

svn+ssh://pythondev@svn.python.org/python/trunk

........
  r76805 | benjamin.peterson | 2009-12-13 13:19:07 -0600 (Sun, 13 Dec 2009) | 7 lines

  accept None as the same as having passed no argument in file types #7349

  This is for consistency with imitation file objects like StringIO and BytesIO.

  This commit also adds a few tests, where they were lacking for concerned
  methods.
........

1 files changed, 26 insertions, 0 deletions

diff --git a/Modules/_io/_iomodule.c b/Modules/_io/_iomodule.c
index 02776f3..dfd66aa 100644
--- a/Modules/_io/_iomodule.c
+++ b/Modules/_io/_iomodule.c
@@ -561,6 +561,30 @@ PyNumber_AsOff_t(PyObject *item, PyObject *err)
     return result;
 }
 
+
+/* Basically the "n" format code with the ability to turn None into -1. */
+int 
+_PyIO_ConvertSsize_t(PyObject *obj, void *result) {
+    Py_ssize_t limit;
+    if (obj == Py_None) {
+        limit = -1;
+    }
+    else if (PyNumber_Check(obj)) {
+        limit = PyNumber_AsSsize_t(obj, PyExc_OverflowError);
+        if (limit == -1 && PyErr_Occurred())
+            return 0;
+    }
+    else {
+        PyErr_Format(PyExc_TypeError,
+                     "integer argument expected, got '%.200s'",
+                     Py_TYPE(obj)->tp_name);
+        return 0;
+    }
+    *((Py_ssize_t *)result) = limit;
+    return 1;
+}
+
+
 static int
 iomodule_traverse(PyObject *mod, visitproc visit, void *arg) {
     _PyIO_State *state = IO_MOD_STATE(mod);
@@ -574,6 +598,7 @@ iomodule_traverse(PyObject *mod, visitproc visit, void *arg) {
     return 0;
 }
 
+
 static int
 iomodule_clear(PyObject *mod) {
     _PyIO_State *state = IO_MOD_STATE(mod);
@@ -591,6 +616,7 @@ iomodule_free(PyObject *mod) {
     iomodule_clear(mod);
 }
 
+
 /*
  * Module definition
  */