bpo-37523: Raise ValueError for I/O operations on a closed zipfile.ZipExtFile. (GH-14658)

Raises ValueError when calling the following on a closed zipfile.ZipExtFile: read, readable, seek, seekable, tell.

1 files changed, 10 insertions, 0 deletions

diff --git a/Lib/zipfile.py b/Lib/zipfile.py
index b0afb9da94..e1d07f2a52 100644
--- a/Lib/zipfile.py
+++ b/Lib/zipfile.py
@@ -889,12 +889,16 @@ class ZipExtFile(io.BufferedIOBase):
         return self._readbuffer[self._offset: self._offset + 512]
 
     def readable(self):
+        if self.closed:
+            raise ValueError("I/O operation on closed file.")
         return True
 
     def read(self, n=-1):
         """Read and return up to n bytes.
         If the argument is omitted, None, or negative, data is read and returned until EOF is reached.
         """
+        if self.closed:
+            raise ValueError("read from closed file.")
         if n is None or n < 0:
             buf = self._readbuffer[self._offset:]
             self._readbuffer = b''
@@ -1031,9 +1035,13 @@ class ZipExtFile(io.BufferedIOBase):
             super().close()
 
     def seekable(self):
+        if self.closed:
+            raise ValueError("I/O operation on closed file.")
         return self._seekable
 
     def seek(self, offset, whence=0):
+        if self.closed:
+            raise ValueError("seek on closed file.")
         if not self._seekable:
             raise io.UnsupportedOperation("underlying stream is not seekable")
         curr_pos = self.tell()
@@ -1082,6 +1090,8 @@ class ZipExtFile(io.BufferedIOBase):
         return self.tell()
 
     def tell(self):
+        if self.closed:
+            raise ValueError("tell on closed file.")
         if not self._seekable:
             raise io.UnsupportedOperation("underlying stream is not seekable")
         filepos = self._orig_file_size - self._left - len(self._readbuffer) + self._offset