Add exception when using --state and referring to a removed test (#12203)

* add test using repro from issue

fix test

more test fixes

fix test

* error on none

* changelog

* use correct fixture pattern

.changes/unreleased/Fixes-20251125-120246.yaml

@@ -0,0 +1,7 @@
+kind: Fixes
+body: ':bug: :snowman: Add exception when using --state and referring to a removed
+  test'
+time: 2025-11-25T12:02:46.635026-05:00
+custom:
+  Author: emmyoop
+  Issue: "10630"

core/dbt/graph/selector_methods.py

@@ -35,7 +35,7 @@ from dbt.contracts.state import PreviousState
 from dbt.node_types import NodeType
 from dbt_common.dataclass_schema import StrEnum
 from dbt_common.events.contextvars import get_project_root
-from dbt_common.exceptions import DbtInternalError, DbtRuntimeError
+from dbt_common.exceptions import CompilationError, DbtInternalError, DbtRuntimeError
 
 from .graph import UniqueId
 
@@ -655,6 +655,16 @@ class StateSelectorMethod(SelectorMethod):
                 continue
             visited_macros.append(macro_uid)
 
+            # If macro_uid is None, it means the macro/test was removed but is still referenced.
+            # Raise a clear error to match the behavior of regular dbt run.
+            if macro_uid is None:
+                raise CompilationError(
+                    f"Node '{node.name}' (in {node.original_file_path}) depends on a macro or test "
+                    f"that does not exist. This can happen when a macro or generic test is removed "
+                    f"but is still referenced. Check for typos and/or install package dependencies "
+                    f"with 'dbt deps'."
+                )
+
             if macro_uid in self.modified_macros:
                 return True
 

tests/functional/defer_state/fixtures.py

@@ -656,3 +656,24 @@ sources:
     tables:
       - name: customers
 """
+
+# Fixtures for test_removed_test_state.py
+sample_test_sql = """
+{% test sample_test(model, column_name) %}
+    select * from {{ model }} where {{ column_name }} is null
+{% endtest %}
+"""
+
+removed_test_model_sql = """
+select 1 as id
+"""
+
+removed_test_schema_yml = """
+version: 2
+models:
+  - name: model_a
+    columns:
+      - name: id
+        data_tests:
+          - sample_test
+"""

tests/functional/defer_state/test_removed_test_state.py

@@ -0,0 +1,124 @@
+import pytest
+
+from dbt.exceptions import CompilationError
+from dbt.tests.util import run_dbt
+from tests.functional.defer_state.fixtures import (
+    removed_test_model_sql,
+    removed_test_schema_yml,
+    sample_test_sql,
+)
+
+
+class TestRemovedGenericTest:
+    """Test that removing a generic test while it's still referenced gives a clear error message."""
+
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "model_a.sql": removed_test_model_sql,
+            "schema.yml": removed_test_schema_yml,
+        }
+
+    @pytest.fixture(scope="class")
+    def tests(self):
+        return {
+            "generic": {
+                "sample_test.sql": sample_test_sql,
+            }
+        }
+
+    def copy_state(self, project):
+        import os
+        import shutil
+
+        if not os.path.exists(f"{project.project_root}/state"):
+            os.makedirs(f"{project.project_root}/state")
+        shutil.copyfile(
+            f"{project.project_root}/target/manifest.json",
+            f"{project.project_root}/state/manifest.json",
+        )
+
+    def test_removed_generic_test_with_state_modified(self, project):
+        """
+        Test that state:modified selector handles missing test macros gracefully.
+
+        Issue #10630: When a generic test is removed but still referenced, using
+        --select state:modified would crash with KeyError: None.
+
+        Solution: We check for None macro_uid in the state selector and raise a clear error.
+        """
+        # Initial run - everything works
+        results = run_dbt(["run"])
+        assert len(results) == 1
+
+        # Save state
+        self.copy_state(project)
+
+        # Remove the generic test file but keep the reference in schema.yml
+        import os
+
+        test_file_path = os.path.join(project.project_root, "tests", "generic", "sample_test.sql")
+        if os.path.exists(test_file_path):
+            os.remove(test_file_path)
+
+        # The key bug fix: dbt run --select state:modified used to crash with KeyError: None
+        # After fix: it should give a clear compilation error during the selection phase
+        with pytest.raises(CompilationError, match="does not exist|macro or test"):
+            run_dbt(["run", "--select", "state:modified", "--state", "state"])
+
+
+class TestRemovedGenericTestStateModifiedGracefulError:
+    """Test that state:modified selector handles missing test macros gracefully."""
+
+    @pytest.fixture(scope="class")
+    def models(self):
+        return {
+            "model_a.sql": removed_test_model_sql,
+            "schema.yml": removed_test_schema_yml,
+        }
+
+    @pytest.fixture(scope="class")
+    def tests(self):
+        return {
+            "generic": {
+                "sample_test.sql": sample_test_sql,
+            }
+        }
+
+    def copy_state(self, project):
+        import os
+        import shutil
+
+        if not os.path.exists(f"{project.project_root}/state"):
+            os.makedirs(f"{project.project_root}/state")
+        shutil.copyfile(
+            f"{project.project_root}/target/manifest.json",
+            f"{project.project_root}/state/manifest.json",
+        )
+
+    def test_list_with_state_modified_after_test_removal(self, project):
+        """
+        Test that state:modified selector handles missing test macros gracefully.
+        This exercises the selector_methods.py code path that was failing with KeyError: None.
+        """
+        # Initial run - everything works
+        results = run_dbt(["run"])
+        assert len(results) == 1
+
+        # Save state
+        self.copy_state(project)
+
+        # Remove the generic test file but keep the reference in schema.yml
+        import os
+
+        test_file_path = os.path.join(project.project_root, "tests", "generic", "sample_test.sql")
+        if os.path.exists(test_file_path):
+            os.remove(test_file_path)
+
+        # dbt run with state:modified should not crash with KeyError: None
+        # After the fix, it should give a clear CompilationError about the missing test
+        # Previously this crashed with KeyError: None in recursively_check_macros_modified
+        with pytest.raises(
+            CompilationError, match="sample_test|does not exist|macro or generic test"
+        ):
+            run_dbt(["run", "--select", "state:modified", "--state", "state"])