Issue #16304: Further performance improvements for BZ2File.
Optimizations suggested by Serhiy Storchaka.
diff --git a/Lib/bz2.py b/Lib/bz2.py
index fe4118f..37918a8 100644
--- a/Lib/bz2.py
+++ b/Lib/bz2.py
@@ -159,15 +159,21 @@
raise ValueError("I/O operation on closed file")
def _check_can_read(self):
- if not self.readable():
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if self._mode not in (_MODE_READ, _MODE_READ_EOF):
raise io.UnsupportedOperation("File not open for reading")
def _check_can_write(self):
- if not self.writable():
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if self._mode != _MODE_WRITE:
raise io.UnsupportedOperation("File not open for writing")
def _check_can_seek(self):
- if not self.readable():
+ if self.closed:
+ raise ValueError("I/O operation on closed file")
+ if self._mode not in (_MODE_READ, _MODE_READ_EOF):
raise io.UnsupportedOperation("Seeking is only supported "
"on files open for reading")
if not self._fp.seekable():