Issue #12175: FileIO.readall() now raises a ValueError instead of an IOError if

the file is closed.

Lib/test/test_io.py

@@ -2467,6 +2467,8 @@ class MiscIOTest(unittest.TestCase):
             self.assertRaises(ValueError, f.read)
             if hasattr(f, "read1"):
                 self.assertRaises(ValueError, f.read1, 1024)
+            if hasattr(f, "readall"):
+                self.assertRaises(ValueError, f.readall)
             if hasattr(f, "readinto"):
                 self.assertRaises(ValueError, f.readinto, bytearray(1024))
             self.assertRaises(ValueError, f.readline)

Misc/NEWS

@@ -75,6 +75,9 @@ Core and Builtins
 Library
 -------
 
+- Issue #12175: FileIO.readall() now raises a ValueError instead of an IOError
+  if the file is closed.
+
 - Issue #12100: Don't reset incremental encoders of CJK codecs at each call to
   their encode() method anymore, but continue to call the reset() method if the
   final argument is True.

Modules/_io/fileio.c

@@ -536,6 +536,8 @@ fileio_readall(fileio *self)
     Py_ssize_t total = 0;
     int n;
 
+    if (self->fd < 0)
+        return err_closed();
     if (!_PyVerify_fd(self->fd))
         return PyErr_SetFromErrno(PyExc_IOError);