Fix: handle duplicate key error when we add a project var or change the project name

sqlmesh/core/context.py

@@ -692,8 +692,11 @@ def load(self, update_schemas: bool = True) -> GenericContext[C]:
                     if snapshot.node.project in self._projects:
                         uncached.add(snapshot.name)
                     else:
-                        store = self._standalone_audits if snapshot.is_audit else self._models
-                        store[snapshot.name] = snapshot.node  # type: ignore
+                        local_store = self._standalone_audits if snapshot.is_audit else self._models
+                        if snapshot.name in local_store:
+                            uncached.add(snapshot.name)
+                        else:
+                            local_store[snapshot.name] = snapshot.node  # type: ignore
 
         for model in self._models.values():
             self.dag.add(model.fqn, model.depends_on)

tests/core/integration/test_multi_repo.py

@@ -421,6 +421,111 @@ def test_multi_hybrid(mocker):
     validate_apply_basics(context, c.PROD, plan.snapshots.values())
 
 
+def test_multi_repo_no_project_to_project(copy_to_temp_path):
+    paths = copy_to_temp_path("examples/multi")
+    repo_1_path = f"{paths[0]}/repo_1"
+    repo_1_config_path = f"{repo_1_path}/config.yaml"
+    with open(repo_1_config_path, "r") as f:
+        config_content = f.read()
+    with open(repo_1_config_path, "w") as f:
+        f.write(config_content.replace("project: repo_1\n", ""))
+
+    context = Context(paths=[repo_1_path], gateway="memory")
+    context._new_state_sync().reset(default_catalog=context.default_catalog)
+    plan = context.plan_builder().build()
+    context.apply(plan)
+
+    # initially models in prod have no project
+    prod_snapshots = context.state_reader.get_snapshots(
+        context.state_reader.get_environment(c.PROD).snapshots
+    )
+    for snapshot in prod_snapshots.values():
+        assert snapshot.node.project == ""
+
+    # we now adopt multi project by adding a project name
+    with open(repo_1_config_path, "r") as f:
+        config_content = f.read()
+    with open(repo_1_config_path, "w") as f:
+        f.write("project: repo_1\n" + config_content)
+
+    context_with_project = Context(
+        paths=[repo_1_path],
+        state_sync=context.state_sync,
+        gateway="memory",
+    )
+    context_with_project._engine_adapter = context.engine_adapter
+    del context_with_project.engine_adapters
+
+    # local models should take precedence to pick up the new project name
+    local_model_a = context_with_project.get_model("bronze.a")
+    assert local_model_a.project == "repo_1"
+    local_model_b = context_with_project.get_model("bronze.b")
+    assert local_model_b.project == "repo_1"
+
+    # also verify the plan works
+    plan = context_with_project.plan_builder().build()
+    context_with_project.apply(plan)
+    validate_apply_basics(context_with_project, c.PROD, plan.snapshots.values())
+
+
+def test_multi_repo_local_model_overrides_prod_from_other_project(copy_to_temp_path):
+    paths = copy_to_temp_path("examples/multi")
+    repo_1_path = f"{paths[0]}/repo_1"
+    repo_2_path = f"{paths[0]}/repo_2"
+
+    context = Context(paths=[repo_1_path, repo_2_path], gateway="memory")
+    context._new_state_sync().reset(default_catalog=context.default_catalog)
+    plan = context.plan_builder().build()
+    assert len(plan.new_snapshots) == 5
+    context.apply(plan)
+
+    prod_model_c = context.get_model("silver.c")
+    assert prod_model_c.project == "repo_2"
+
+    with open(f"{repo_1_path}/models/c.sql", "w") as f:
+        f.write(
+            dedent("""\
+            MODEL (
+              name silver.c,
+              kind FULL
+            );
+
+            SELECT DISTINCT col_a, col_b
+            FROM bronze.a
+        """)
+        )
+
+    # silver.c exists locally in repo 1 now AND in prod under repo_2
+    context_repo1 = Context(
+        paths=[repo_1_path],
+        state_sync=context.state_sync,
+        gateway="memory",
+    )
+    context_repo1._engine_adapter = context.engine_adapter
+    del context_repo1.engine_adapters
+
+    # local model should take precedence and its project should reflect the new project name
+    local_model_c = context_repo1.get_model("silver.c")
+    assert local_model_c.project == "repo_1"
+
+    rendered = context_repo1.render("silver.c").sql()
+    assert "col_b" in rendered
+
+    # its downstream dependencies though should still be picked up
+    plan = context_repo1.plan_builder().build()
+    directly_modified_names = {snapshot.name for snapshot in plan.directly_modified}
+    assert '"memory"."silver"."c"' in directly_modified_names
+    assert '"memory"."silver"."d"' in directly_modified_names
+    missing_interval_names = {s.snapshot_id.name for s in plan.missing_intervals}
+    assert '"memory"."silver"."c"' in missing_interval_names
+    assert '"memory"."silver"."d"' in missing_interval_names
+
+    context_repo1.apply(plan)
+    validate_apply_basics(context_repo1, c.PROD, plan.snapshots.values())
+    result = context_repo1.fetchdf("SELECT * FROM memory.silver.c")
+    assert "col_b" in result.columns
+
+
 def test_engine_adapters_multi_repo_all_gateways_gathered(copy_to_temp_path):
     paths = copy_to_temp_path("examples/multi")
     repo_1_path = paths[0] / "repo_1"