Fix: Prepopulate the model's depends on in-memory cache for converted…

… dbt models (#3074)

sqlmesh/dbt/model.py

@@ -422,7 +422,7 @@ def to_sqlmesh(self, context: DbtContext) -> Model:
                     "target_lag": self.target_lag,
                 }
 
-        return create_sql_model(
+        model = create_sql_model(
             self.canonical_name(context),
             query,
             dialect=model_dialect,
@@ -431,6 +431,12 @@ def to_sqlmesh(self, context: DbtContext) -> Model:
             **optional_kwargs,
             **model_kwargs,
         )
+        # Prepopulate the _full_depends_on cache with dependencies sourced directly from the manifest.
+        # This ensures that we bypass query rendering that would otherwise be required to extract additional
+        # dependencies from the model's SQL.
+        # Note: any table dependencies that are not referenced using the `ref` macro will not be included.
+        model._full_depends_on = model.depends_on_
+        return model
 
     def _dbt_max_partition_blob(self) -> t.Optional[str]:
         """Returns a SQL blob which declares the _dbt_max_partition variable. Only applicable to BigQuery."""

tests/dbt/test_config.py

@@ -789,3 +789,22 @@ def test_variable_override():
         variables={"yet_another_var": 2, "start": "2021-01-01"},
     )
     assert project.packages["sushi"].variables["yet_another_var"] == 2
+
+
+def test_depends_on(assert_exp_eq, sushi_test_project):
+    # Case 1: using an undefined variable without a default value
+    context = sushi_test_project.context
+
+    model_config = ModelConfig(
+        alias="sushi.test",
+        sql="SELECT * FROM {{ ref('waiter_revenue_by_day') }} JOIN other_table",
+        dependencies=Dependencies(refs=["waiter_revenue_by_day"]),
+    )
+
+    sqlmesh_model = model_config.to_sqlmesh(context)
+    assert sqlmesh_model.depends_on_ == {'"memory"."sushi"."waiter_revenue_by_day_v2"'}
+    assert sqlmesh_model.depends_on == {'"memory"."sushi"."waiter_revenue_by_day_v2"'}
+    assert sqlmesh_model.full_depends_on == {'"memory"."sushi"."waiter_revenue_by_day_v2"'}
+
+    # Make sure the query wasn't rendered
+    assert not sqlmesh_model._query_renderer._cache