add circular import test

tests/test_env_resolution.py

@@ -1,5 +1,7 @@
 from pathlib import Path
 
+import pytest
+
 from src.coordinator import Coordinator
 from src.env_file_helper import DependencyRule, EnvFile, sort_env_files_by_rule
 
@@ -22,6 +24,20 @@ def test_complex_sorting() -> None:
     assert sorted_env_files[0].env_type == "e"
 
 
+def test_circular_import() -> None:
+    """This test will raise ValueError because the example input cannot be correctly ordered"""
+    demo_rules = [
+        DependencyRule("a", "b"),
+        DependencyRule("b", "c"),
+        DependencyRule("c", "a"),
+    ]
+
+    demo_types = ["a", "b", "c"]
+    env_files = [EnvFile(env_type=t, env_path=Path(), config=dict()) for t in demo_types]
+    with pytest.raises(ValueError):
+        sort_env_files_by_rule(env_files, demo_rules)
+
+
 def test_real_env_files() -> None:
     """authentik should be first"""