Fix: ensure external is not expanded

Author: tobymao

sqlmesh/core/renderer.py

@@ -212,7 +212,12 @@ def _expand(node: exp.Expression) -> exp.Expression:
                 if isinstance(node, exp.Table) and snapshots:
                     name = exp.table_name(node)
                     model = snapshots[name].model if name in snapshots else None
-                    if name in expand and model and not model.is_seed:
+                    if (
+                        name in expand
+                        and model
+                        and not model.is_seed
+                        and not model.kind.is_external
+                    ):
                         return model.render_query(
                             start=start,
                             end=end,

sqlmesh/core/snapshot/definition.py

@@ -223,6 +223,9 @@ def _table_name(self, version: str, is_dev: bool, for_read: bool) -> str:
             is_dev: Whether the table name will be used in development mode.
             for_read: Whether the table name will be used for reading by a different snapshot.
         """
+        if self.is_external:
+            return self.name
+
         if is_dev and for_read:
             # If this snapshot is used for **reading**, return a temporary table
             # only if this snapshot captures a direct forward-only change applied to its model.

tests/core/test_schema_loader.py

@@ -7,6 +7,7 @@
 from sqlmesh.core import constants as c
 from sqlmesh.core.dialect import parse
 from sqlmesh.core.model import load_model
+from sqlmesh.core.snapshot import SnapshotChangeCategory
 
 
 @pytest.fixture(autouse=True)
@@ -68,6 +69,10 @@ def test_create_external_models(sushi_context):
         "name": exp.DataType.build("VARCHAR"),
     }
 
+    snapshot = sushi_context.snapshots["sushi.raw_fruits"]
+    snapshot.categorize_as(SnapshotChangeCategory.BREAKING)
+    assert snapshot.table_name() == "sushi.raw_fruits"
+
     fruits = sushi_context.models["sushi.fruits"]
     assert not fruits.kind.is_symbolic
     assert not fruits.kind.is_external