Add $setUnion accumulator tests by alinaliBQ · Pull Request #254 · documentdb/functional-tests

alinaliBQ · 2026-05-29T22:31:35Z

This change adds tests for the $setUnion accumulator operator.

Add accumulator operator tests for $setUnion. Tests database $setUnion behavior, output collection, syntax, and expected errors.
Integration tests are in documentdb_tests/compatibility/tests/core/operator/accumulators/test_accumulators_ setUnion_integration.py

Add compatibility test for accumulator operators (11 total) #28

alinaliBQ · 2026-05-29T22:38:13Z

+    AccumulatorTestCase(
+        "error_prop_divide_by_zero_field_path",
+        docs=[{"_id": 0, "v": 0}],
+        pipeline=[
+            {"$sort": {"_id": 1}},
+            {
+                "$group": {
+                    "_id": None,
+                    "result": {"$setUnion": {"$let": {"vars": {}, "in": [{"$divide": [1, "$v"]}]}}},
+                }
+            },
+        ],
+        error_code=DIVIDE_BY_ZERO_V2_ERROR,
+        msg="$setUnion should propagate $divide by zero when divisor comes from field path",
+    ),
+    AccumulatorTestCase(
+        "error_prop_divide_by_zero_later_doc",
+        docs=[{"_id": 0, "v": 1}, {"_id": 1, "v": 0}],
+        pipeline=[
+            {"$sort": {"_id": 1}},
+            {
+                "$group": {
+                    "_id": None,
+                    "result": {"$setUnion": {"$let": {"vars": {}, "in": [{"$divide": [1, "$v"]}]}}},
+                }
+            },
+        ],
+        error_code=DIVIDE_BY_ZERO_V2_ERROR,
+        msg="$setUnion should propagate error even when failing doc is not the first",
+    ),


Added 2 divide tests. Also no pytest.approx(math.nan... in this PR

documentdb-triage-tool · 2026-05-29T23:40:40Z

🤖 Auto-triaged by documentdb-triage-tool.

Applied: compatibility test, enhancement
Project fields suggested: Component test-coverage · Priority P2 · Effort XL · Status Needs Review
Confidence: 0.92 (mixed)

Reasoning

component from path globs (test-coverage); effort from diff stats (2304+0 LOC, 9 files); LLM: Adds new integration test coverage for the $setUnion accumulator operator under the compatibility tests path, expanding functional test surface area.

If a label is wrong, remove it manually and ping @patty-chow so the rules can be tuned. The bot will not re-label items that already have component labels.

Rishabh998 · 2026-06-02T19:36:08Z

+        msg="$setUnion should work with compound _id grouping key",
+    ),
+]
+


can we add a test which put documents into different groups?

Here most of them have _id:null

I think having documents into different groups might be an out of scope as @eerxuan stated here: #257 (comment)
we are only testing the $setUnion accumulator, not broader document grouping

Rishabh998 · 2026-06-02T19:38:35Z

+]
+
+# Property [Object Element Deduplication]: objects are compared by structure
+# including key order.


Can we add a test with mixed element types within the same array?

Eg:

docs=[ {"v": [1, "a", {"id": 1}, None, [1, 2]]}, {"v": ["a", 2, {"id": 1}, None]}, ]

added SETUNION_MIXED_ELEMENT_TYPE_TESTS for this

Rishabh998 · 2026-06-02T19:39:38Z

+]
+
+# Property [Grouping Key Variations]: $setUnion works with different _id
+# grouping expressions.


Lets also add a test where we are doing $group followed by a $group, with both $setUnion accumulator ops

added SETUNION_CHAINED_GROUP_TESTS for this

Rishabh998 · 2026-06-02T19:42:37Z

+        msg="$setUnion should accept simple field path expression",
+    ),
+    AccumulatorTestCase(
+        "expr_nested_field_path",


Here can we add a test case where nested path is missing in one doc.

like.

docs=[ {"a": {"b": [1, 2]}}, {"a": {}}, -----------------------> a exists, b missing {"a": {"b": [2, 3]}}, {"c": 1}, ----------->a missing entirely (combination where a and b are missing and we are doing set union on "$a", $a.b, $a.b.c etc where a is array+ non array case , b is array + non array ......) ]

Added tests SETUNION_MISSING_NESTED_PATH_TESTS for this

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

- Add type_error_code test case to errors.py - Add Code to all_bson_types_distinct and all_bson_types_dedup in element_dedup.py - Add __init__.py to setUnion directory - Update expected sizes from 17 to 18 Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

alinaliBQ

@Rishabh998 addressed comments. Regarding https://github.com/documentdb/functional-tests/pull/254/changes#r3343920563, I did not add any test since tests with different grouping is out of scope for accumulator tests

alinaliBQ · 2026-06-02T21:08:57Z

+]
+
+# Property [Grouping Key Variations]: $setUnion works with different _id
+# grouping expressions.


added SETUNION_CHAINED_GROUP_TESTS for this

alinaliBQ · 2026-06-02T21:12:54Z

+        msg="$setUnion should work with compound _id grouping key",
+    ),
+]
+


I think having documents into different groups might be an out of scope as @eerxuan stated here: #257 (comment)
we are only testing the $setUnion accumulator, not broader document grouping

alinaliBQ · 2026-06-02T21:14:58Z

+]
+
+# Property [Object Element Deduplication]: objects are compared by structure
+# including key order.


added SETUNION_MIXED_ELEMENT_TYPE_TESTS for this

alinaliBQ · 2026-06-02T21:28:05Z

+        msg="$setUnion should accept simple field path expression",
+    ),
+    AccumulatorTestCase(
+        "expr_nested_field_path",


Added tests SETUNION_MISSING_NESTED_PATH_TESTS for this

alinaliBQ requested a review from a team as a code owner May 29, 2026 22:31

alinaliBQ marked this pull request as draft May 29, 2026 22:31

alinaliBQ commented May 29, 2026

View reviewed changes

alinaliBQ marked this pull request as ready for review May 29, 2026 22:40

documentdb-triage-tool Bot added compatibility test Compatibility test related enhancement New feature or request labels May 29, 2026

Rishabh998 reviewed Jun 2, 2026

View reviewed changes

alinaliBQ added 9 commits June 2, 2026 13:52

initial generated tests

fba8d56

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

update test code

4be6ea9

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

remove stage and expression tests

be805f4

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

add arity error and expression tests

6d8dcc8

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

Add integration tests

abafa70

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

add divide tests

71b5522

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

fix test grouping

65e0c82

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

remove exact duplicates and rename tests to be more clear

dac86ef

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

alinaliBQ force-pushed the setUnion branch from 305acc2 to 5181056 Compare June 2, 2026 20:52

alinaliBQ added 4 commits June 2, 2026 14:06

add missing tests

ce40a09

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

add SETUNION_CHAINED_GROUP_TESTS

1db7afb

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

Add SETUNION_MIXED_ELEMENT_TYPE_TESTS

1fc1e44

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

SETUNION_MISSING_NESTED_PATH_TESTS added

eab47f9

Signed-off-by: Alina (Xi) Li <Alina.Li@improving.com>

alinaliBQ commented Jun 2, 2026

View reviewed changes

Conversation

alinaliBQ commented May 29, 2026

Uh oh!

Choose a reason for hiding this comment

Uh oh!

documentdb-triage-tool Bot commented May 29, 2026

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

alinaliBQ left a comment

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Choose a reason for hiding this comment

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

2 participants