From bd49e17cb740d0e6eb5695656ec066b24097516e Mon Sep 17 00:00:00 2001
From: George Sittas <giwrgos.sittas@gmail.com>
Date: Mon, 9 Jun 2025 19:56:11 +0300
Subject: [PATCH] Fix: normalize datetime values to strings in unit tests

---
 sqlmesh/core/test/definition.py | 11 ++++++++++-
 tests/core/test_test.py         | 31 +++++++++++++++++++++++++++++++
 2 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/sqlmesh/core/test/definition.py b/sqlmesh/core/test/definition.py
index a766706801..e43b8b215c 100644
--- a/sqlmesh/core/test/definition.py
+++ b/sqlmesh/core/test/definition.py
@@ -258,12 +258,21 @@ def assert_equal(
         actual = actual.replace({np.nan: None})
         expected = expected.replace({np.nan: None})
 
+        # We define this here to avoid a top-level import of numpy and pandas
+        DATETIME_TYPES = (
+            datetime.datetime,
+            datetime.date,
+            datetime.time,
+            np.datetime64,
+            pd.Timestamp,
+        )
+
         def _to_hashable(x: t.Any) -> t.Any:
             if isinstance(x, (list, np.ndarray)):
                 return tuple(_to_hashable(v) for v in x)
             if isinstance(x, dict):
                 return tuple((k, _to_hashable(v)) for k, v in x.items())
-            return str(x) if not isinstance(x, t.Hashable) else x
+            return str(x) if isinstance(x, DATETIME_TYPES) or not isinstance(x, t.Hashable) else x
 
         actual = actual.apply(lambda col: col.map(_to_hashable))
         expected = expected.apply(lambda col: col.map(_to_hashable))
diff --git a/tests/core/test_test.py b/tests/core/test_test.py
index a05e66e48f..9478f4aa6b 100644
--- a/tests/core/test_test.py
+++ b/tests/core/test_test.py
@@ -2609,3 +2609,34 @@ def test_model_test_text_result_reporting_no_traceback(
     prefix = "ERROR" if is_error else "FAIL"
     assert f"{prefix}: test_foo (None)" in output
     assert "Exception: failure" in output
+
+
+def test_timestamp_normalization() -> None:
+    model = _create_model(
+        "SELECT id, array_agg(timestamp_col::timestamp) as agg_timestamp_col FROM temp_model_with_timestamp GROUP BY id",
+        meta="MODEL (name foo, kind FULL)",
+    )
+
+    _check_successful_or_raise(
+        _create_test(
+            body=load_yaml(
+                """
+    test_foo:
+      model: temp_agg_model_with_timestamp
+      inputs:
+        temp_model_with_timestamp:
+          rows:
+            - id: "id1"
+              timestamp_col: "2024-01-02T15:00:00"
+      outputs:
+        query:
+          rows:
+            - id: id1
+              agg_timestamp_col: ["2024-01-02T15:00:00.000000"]
+                """
+            ),
+            test_name="test_foo",
+            model=model,
+            context=Context(config=Config(model_defaults=ModelDefaultsConfig(dialect="duckdb"))),
+        ).run()
+    )