[3.10] bpo-25130: Add calls of gc.collect() in tests to support PyPy (GH-28005) (GH-28027)
(cherry picked from commit 2a8127cafe1d196f858a3ecabf5f1df3eebf9a12)
Co-authored-by: Serhiy Storchaka <storchaka@gmail.com>
diff --git a/Lib/test/test_io.py b/Lib/test/test_io.py
index 32c29ea..273545a 100644
--- a/Lib/test/test_io.py
+++ b/Lib/test/test_io.py
@@ -4372,6 +4372,31 @@ def check_interrupted_write(self, item, bytes, **fdopen_kwargs):
"""Check that a partial write, when it gets interrupted, properly
invokes the signal handler, and bubbles up the exception raised
in the latter."""
+
+ # XXX This test has three flaws that appear when objects are
+ # XXX not reference counted.
+
+ # - if wio.write() happens to trigger a garbage collection,
+ # the signal exception may be raised when some __del__
+ # method is running; it will not reach the assertRaises()
+ # call.
+
+ # - more subtle, if the wio object is not destroyed at once
+ # and survives this function, the next opened file is likely
+ # to have the same fileno (since the file descriptor was
+ # actively closed). When wio.__del__ is finally called, it
+ # will close the other's test file... To trigger this with
+ # CPython, try adding "global wio" in this function.
+
+ # - This happens only for streams created by the _pyio module,
+ # because a wio.close() that fails still consider that the
+ # file needs to be closed again. You can try adding an
+ # "assert wio.closed" at the end of the function.
+
+ # Fortunately, a little gc.collect() seems to be enough to
+ # work around all these issues.
+ support.gc_collect() # For PyPy or other GCs.
+
read_results = []
def _read():
s = os.read(r, 1)