Chore: Validate start and end dates during plan build time

Author: themisvaltinos

sqlmesh/core/context.py

@@ -1603,6 +1603,28 @@ def plan_builder(
                 execution_time or now(),
             )
 
+            # Validate that the start is not greater than the end date / time
+            effective_start = start or default_start
+            effective_end = end or default_end
+            if effective_start is not None and effective_end is not None:
+                start_ts = to_timestamp(effective_start)
+                end_ts = to_timestamp(effective_end)
+                if start_ts > end_ts:
+                    for model_name in (
+                        set(backfill_models or {})
+                        | set(modified_model_names)
+                        | set(max_interval_end_per_model)
+                    ):
+                        if snapshot := snapshots.get(model_name):
+                            if (
+                                snapshot.node.start is None
+                                or to_timestamp(snapshot.node.start) > end_ts
+                            ):
+                                raise SQLMeshError(
+                                    f"Start date / time ({to_datetime(start_ts)}) can't be greater than end date / time ({to_datetime(end_ts)}).\n"
+                                    f"Set the `start` attribute in your project config model defaults to avoid this issue."
+                                )
+
             # Refresh snapshot intervals to ensure that they are up to date with values reflected in the max_interval_end_per_model.
             self.state_sync.refresh_snapshot_intervals(context_diff.snapshots.values())
 

tests/core/test_context.py

@@ -3007,3 +3007,59 @@ def test_uppercase_gateway_external_models(tmp_path):
     assert len(uppercase_in_yaml_models) == 1, (
         f"External model with uppercase gateway in YAML should be found. Found {len(uppercase_in_yaml_models)} models"
     )
+
+
+def test_plan_no_start_configured():
+    context = Context(config=Config())
+    context.upsert_model(
+        load_sql_based_model(
+            parse(
+                """
+                MODEL(
+                    name db.xvg,
+                    kind INCREMENTAL_BY_TIME_RANGE (
+                        time_column ds
+                    ),
+                    cron '@daily'
+                );
+
+                SELECT id, ds FROM (VALUES
+                    ('1', '2020-01-01'),
+                ) data(id, ds)
+                WHERE ds BETWEEN @start_ds AND @end_ds
+                """
+            )
+        )
+    )
+
+    prod_plan = context.plan(auto_apply=True)
+    assert len(prod_plan.new_snapshots) == 1
+
+    context.upsert_model(
+        load_sql_based_model(
+            parse(
+                """
+                MODEL(
+                    name db.xvg,
+                    kind INCREMENTAL_BY_TIME_RANGE (
+                        time_column ds
+                    ),
+                    cron '@daily',
+                    physical_properties ('some_prop' = 1),
+                );
+
+                SELECT id, ds FROM (VALUES
+                    ('1', '2020-01-01'),
+                ) data(id, ds)
+                WHERE ds BETWEEN @start_ds AND @end_ds
+                """
+            )
+        )
+    )
+
+    # This should raise an error because the model has no start configured and the end time is less than the start time which will be calculated from the intervals
+    with pytest.raises(
+        SQLMeshError,
+        match=r"Set the `start` attribute in your project config model defaults to avoid this issue",
+    ):
+        context.plan("dev", execution_time="1999-01-05")