1 files changed, 16 insertions, 7 deletions
diff --git a/Lib/_pyio.py b/Lib/_pyio.py
index a870de5b532..fb2a6d049ca 100644
--- a/Lib/_pyio.py
+++ b/Lib/_pyio.py
@@ -407,6 +407,9 @@ class IOBase(metaclass=abc.ABCMeta):
         if closed:
             return
 
+        if dealloc_warn := getattr(self, "_dealloc_warn", None):
+            dealloc_warn(self)
+
         # If close() fails, the caller logs the exception with
         # sys.unraisablehook. close() must be called at the end at __del__().
         self.close()
@@ -645,8 +648,6 @@ class RawIOBase(IOBase):
         self._unsupported("write")
 
 io.RawIOBase.register(RawIOBase)
-from _io import FileIO
-RawIOBase.register(FileIO)
 
 
 class BufferedIOBase(IOBase):
@@ -853,6 +854,10 @@ class _BufferedIOMixin(BufferedIOBase):
         else:
             return "<{}.{} name={!r}>".format(modname, clsname, name)
 
+    def _dealloc_warn(self, source):
+        if dealloc_warn := getattr(self.raw, "_dealloc_warn", None):
+            dealloc_warn(source)
+
     ### Lower-level APIs ###
 
     def fileno(self):
@@ -1563,7 +1568,8 @@ class FileIO(RawIOBase):
                     if not isinstance(fd, int):
                         raise TypeError('expected integer from opener')
                     if fd < 0:
-                        raise OSError('Negative file descriptor')
+                        # bpo-27066: Raise a ValueError for bad value.
+                        raise ValueError(f'opener returned {fd}')
                 owned_fd = fd
                 if not noinherit_flag:
                     os.set_inheritable(fd, False)
@@ -1600,12 +1606,11 @@ class FileIO(RawIOBase):
             raise
         self._fd = fd
 
-    def __del__(self):
+    def _dealloc_warn(self, source):
         if self._fd >= 0 and self._closefd and not self.closed:
             import warnings
-            warnings.warn('unclosed file %r' % (self,), ResourceWarning,
+            warnings.warn(f'unclosed file {source!r}', ResourceWarning,
                           stacklevel=2, source=self)
-            self.close()
 
     def __getstate__(self):
         raise TypeError(f"cannot pickle {self.__class__.__name__!r} object")
@@ -1780,7 +1785,7 @@ class FileIO(RawIOBase):
         if not self.closed:
             self._stat_atopen = None
             try:
-                if self._closefd:
+                if self._closefd and self._fd >= 0:
                     os.close(self._fd)
             finally:
                 super().close()
@@ -2689,6 +2694,10 @@ class TextIOWrapper(TextIOBase):
     def newlines(self):
         return self._decoder.newlines if self._decoder else None
 
+    def _dealloc_warn(self, source):
+        if dealloc_warn := getattr(self.buffer, "_dealloc_warn", None):
+            dealloc_warn(source)
+
 
 class StringIO(TextIOWrapper):
     """Text I/O implementation using an in-memory buffer.