[arrow] branch master updated: GH-15141: [C++] fix for unstable test due to unstable sort (#15142)

[we...@apache.org]

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westonpace pushed a commit to branch master
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The following commit(s) were added to refs/heads/master by this push:
     new 5a57e6dd1e GH-15141: [C++] fix for unstable test due to unstable sort (#15142)
5a57e6dd1e is described below

commit 5a57e6dd1e4b1d89ecabe86b45d063619a0f2f54
Author: Weston Pace <we...@gmail.com>
AuthorDate: Sat Dec 31 21:57:30 2022 -0800

    GH-15141: [C++] fix for unstable test due to unstable sort (#15142)
    
    The sorting done by orderby is not stable.  This means, given the input:
    
    a | b
    --- | ---
    1 | false
    1 | true
    
    the test could have generated both `[false, true]` and `[true, false]` for the `b` column.  We likely did not encounter this before https://github.com/apache/arrow/commit/498b645e1d09306bf5399a9a019a5caa99513815 because the entire thing was run serially (even though there was a `parallel` option it was not setup correctly).
    
    Now that things are properly running parallel the results are non-deterministic.  We could remove the `b` column but I feel it is a better stress test to have at least one payload column.  So I changed the test to only compare the key array and not the payload array.
    * Closes: #15141
    
    Authored-by: Weston Pace <we...@gmail.com>
    Signed-off-by: Weston Pace <we...@gmail.com>
---
 cpp/src/arrow/compute/exec/plan_test.cc | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/cpp/src/arrow/compute/exec/plan_test.cc b/cpp/src/arrow/compute/exec/plan_test.cc
index 6db069cd9f..2db6c78d4c 100644
--- a/cpp/src/arrow/compute/exec/plan_test.cc
+++ b/cpp/src/arrow/compute/exec/plan_test.cc
@@ -808,7 +808,9 @@ TEST(ExecPlanExecution, StressSourceOrderBy) {
                            TableFromExecBatches(input_schema, random_data.batches));
       ASSERT_OK_AND_ASSIGN(auto sort_indices, SortIndices(original, options));
       ASSERT_OK_AND_ASSIGN(auto expected, Take(original, sort_indices));
-      AssertTablesEqual(*actual, *expected.table());
+      AssertSchemaEqual(actual->schema(), expected.table()->schema());
+      AssertArraysEqual(*actual->column(0)->chunk(0),
+                        *expected.table()->column(0)->chunk(0));
     }
   }
 }