[C++][Python] Sporadic asof join test failure

[pitrou]

Describe the bug, including details regarding any error messages, version, and platform.

I sporadically get this failure when running the PyArrow tests locally:

__________________________________________________________________________ test_table_join_asof ___________________________________________________________________________
Traceback (most recent call last):
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/runner.py", line 340, in from_call
 result: Optional[TResult] = func()
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/runner.py", line 240, in <lambda>
 lambda: runtest_hook(item=item, **kwds), when=when, reraise=reraise
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_hooks.py", line 501, in __call__
 return self._hookexec(self.name, self._hookimpls.copy(), kwargs, firstresult)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_manager.py", line 119, in _hookexec
 return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 181, in _multicall
 return outcome.get_result()
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_result.py", line 99, in get_result
 raise exc.with_traceback(exc.__traceback__)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 166, in _multicall
 teardown.throw(outcome._exception)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/threadexception.py", line 87, in pytest_runtest_call
 yield from thread_exception_runtest_hook()
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/threadexception.py", line 63, in thread_exception_runtest_hook
 yield
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 166, in _multicall
 teardown.throw(outcome._exception)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/unraisableexception.py", line 90, in pytest_runtest_call
 yield from unraisable_exception_runtest_hook()
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/unraisableexception.py", line 65, in unraisable_exception_runtest_hook
 yield
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 166, in _multicall
 teardown.throw(outcome._exception)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/logging.py", line 849, in pytest_runtest_call
 yield from self._runtest_for(item, "call")
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/logging.py", line 832, in _runtest_for
 yield
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 166, in _multicall
 teardown.throw(outcome._exception)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/capture.py", line 883, in pytest_runtest_call
 return (yield)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 166, in _multicall
 teardown.throw(outcome._exception)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/skipping.py", line 256, in pytest_runtest_call
 return (yield)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 102, in _multicall
 res = hook_impl.function(*args)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/runner.py", line 182, in pytest_runtest_call
 raise e
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/runner.py", line 172, in pytest_runtest_call
 item.runtest()
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/python.py", line 1772, in runtest
 self.ihook.pytest_pyfunc_call(pyfuncitem=self)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_hooks.py", line 501, in __call__
 return self._hookexec(self.name, self._hookimpls.copy(), kwargs, firstresult)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_manager.py", line 119, in _hookexec
 return self._inner_hookexec(hook_name, methods, kwargs, firstresult)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 138, in _multicall
 raise exception.with_traceback(exception.__traceback__)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/pluggy/_callers.py", line 102, in _multicall
 res = hook_impl.function(*args)
 File "/home/antoine/mambaforge/envs/pyarrow/lib/python3.10/site-packages/_pytest/python.py", line 195, in pytest_pyfunc_call
 result = testfunction(**testargs)
 File "/home/antoine/arrow/dev/python/pyarrow/tests/test_table.py", line 2800, in test_table_join_asof
 assert r.combine_chunks() == pa.table({
AssertionError: assert pyarrow.Table\ncolA: int64\ncol2: string\ncolC: double\n----\ncolA: [[1,1,5,6,7]]\ncol2: [["a","b","a","b","f"]]\ncolC: [[null,null,null,null,null]] == pyarrow.Table\ncolA: int64\ncol2: string\ncolC: double\n----\ncolA: [[1,1,5,6,7]]\ncol2: [["a","b","a","b","f"]]\ncolC: [[1,null,null,null,null]]
 
 Full diff:
 pyarrow.Table
 colA: int64
 col2: string
 colC: double
 ----
 colA: [[1,1,5,6,7]]
 col2: [["a","b","a","b","f"]]
 - colC: [[1,null,null,null,null]]
 ? ^
 + colC: [[null,null,null,null,null]]
 ? ^^^^
========================================================================= short test summary info =========================================================================
FAILED pyarrow/tests/test_table.py::test_table_join_asof - assert pyarrow.Table\ncolA: int64\ncol2: string\ncolC: double\n----\ncolA: [[1,1,5,6,7]]\ncol2: [["a","b","a","b","f"]]\ncolC: [[null,null,null,null,null]] == pyarrow...

Component(s)

C++, Python

[pitrou]

cc @JerAguilon

[jorisvandenbossche]

This also happened in one nightly build in the last run: https://github.com/ursacomputing/crossbow/actions/runs/8351957186/job/22861244165

[zanmato1984]

Repro in C++, at the chance of about one failure of tens.

TEST(AsofJoinTest, Flaky) {
 std::vector<TypeHolder> left_types = {int64(), utf8()};
 auto left_batch = ExecBatchFromJSON(
 left_types, R"([[1, "a"], [1, "b"], [5, "a"], [6, "b"], [7, "f"]])");
 std::vector<TypeHolder> right_types = {int64(), utf8(), float64()};
 auto right_batch =
 ExecBatchFromJSON(right_types, R"([[2, "a", 1.0], [9, "b", 3.0], [15, "g", 5.0]])");

 Declaration left{
 "exec_batch_source",
 ExecBatchSourceNodeOptions(schema({field("colA", int64()), field("col2", utf8())}),
 {std::move(left_batch)})};
 Declaration right{
 "exec_batch_source",
 ExecBatchSourceNodeOptions(schema({field("colB", int64()), field("col3", utf8()),
 field("colC", float64())}),
 {std::move(right_batch)})};
 AsofJoinNodeOptions asof_join_opts({{{"colA"}, {{"col2"}}}, {{"colB"}, {{"col3"}}}}, 1);
 Declaration asof_join{"asofjoin", {left, right}, asof_join_opts};

 ASSERT_OK_AND_ASSIGN(auto result, DeclarationToExecBatches(asof_join));

 std::vector<TypeHolder> exp_types = {int64(), utf8(), float64()};
 auto exp_batch = ExecBatchFromJSON(
 exp_types,
 R"([[1, "a", 1.0], [1, "b", null], [5, "a", null], [6, "b", null], [7, "f", null]])");
 AssertExecBatchesEqualIgnoringOrder(result.schema, {exp_batch}, result.batches);
}

[zanmato1984]

This is causing wrong result so I'm adding critical label.