Rename tests/parallel to tests/concurrency and add integration tests for Producer close()/transaction races

Author: ojasvajain

tests/parallel/__init__.py tests/concurrency/__init__.pytests/parallel/__init__.py renamed to tests/concurrency/__init__.py

@@ -15,29 +15,21 @@
 # limitations under the License.
 
 """
-Shared test infrastructure for tests/parallel/.
+Shared test infrastructure for tests/concurrency/.
 
 Tests here deliberately race Producer/Consumer methods against each other,
 so a real regression can segfault the process instead of just failing an
 assertion. subprocess_isolated() below runs a decorated test in a fresh
 `python -m pytest` subprocess, so a crash only fails that one test instead
 of taking down the whole suite.
-
-This is a plain module, not conftest.py: conftest.py is auto-loaded by
-pytest's own plugin machinery and isn't meant to be imported as a regular
-module -- doing so (`from tests.parallel.conftest import ...`) is not
-guaranteed to resolve the same way from a re-invoked subprocess as it does
-under pytest's own collection, and failed with
-"ModuleNotFoundError: No module named 'tests.parallel.conftest'" in
-exactly that scenario.
 """
 
 import functools
 import os
 import subprocess
 import sys
 
-_SUBPROCESS_MARKER_ENV = "_PARALLEL_TESTS_SUBPROCESS"
+_SUBPROCESS_MARKER_ENV = "_CONCURRENCY_TESTS_SUBPROCESS"
 _SUBPROCESS_TIMEOUT_SECONDS = 120
 
 

tests/parallel/_subprocess_isolation.py …sts/concurrency/_subprocess_isolation.pytests/parallel/_subprocess_isolation.py renamed to tests/concurrency/_subprocess_isolation.py tests/parallel/_subprocess_isolation.py renamed to tests/concurrency/_subprocess_isolation.py

@@ -18,7 +18,7 @@
 import time
 
 from confluent_kafka import Consumer, Producer, TopicPartition
-from tests.parallel._subprocess_isolation import subprocess_isolated
+from tests.concurrency._subprocess_isolation import subprocess_isolated
 
 ###############################################################################
 # Tests for races between Producer.close() and concurrent calls to
@@ -287,10 +287,7 @@ def run_poll():
     assert poll_finished_at is not None, "poll() never finished"
 
     # close() should have waited for close to the actual remaining poll()
-    # duration, not a fixed guess -- a slower/loaded machine can take longer
-    # to reach close_start, shrinking how much of poll_duration is actually
-    # left to wait for, so we compare against what really happened instead
-    # of a hardcoded constant.
+    # duration
     close_duration = close_end - close_start
     remaining_poll_duration = poll_finished_at - close_start
     assert close_duration >= remaining_poll_duration * 0.9, (