fix: fix --name registry lookup (case and sys.path/sys.modules shadowing)

Two bugs prevented --name from finding servers in the caldav test registry:

1. The caldav library capitalised its server names (Radicale, Xandikos).
   The registry lookup now falls back to a case-insensitive search when
   the exact key is not found.

2. The caldav-server-tester's own tests/ package shadows the caldav
   project's tests/test_servers module — either via sys.modules (if
   already imported) or via '' (CWD) in sys.path.  Switch from
   `from tests.test_servers import …` to loading the module directly
   with importlib.util.spec_from_file_location, bypassing sys.path
   resolution entirely.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: tobixen

CHANGELOG.md

@@ -6,12 +6,17 @@ This file should adhere to [Keep a Changelog](https://keepachangelog.com/en/1.1.
 
 This project should adhere to [Semantic Versioning](https://semver.org/spec/v2.0.0.html), though some earlier releases may be incompatible with the SemVer standard.
 
-## [Unreleased]
+## [1.0.1] - 2026-03-19
+
+### Fixed
+- `--name radicale` (and other lowercase names) failed to find servers in the caldav test registry after the caldav library renamed its server entries to capitalised names (`Radicale`, `Xandikos`).  The registry lookup is now case-insensitive.
+- `--name` registry lookup silently returned nothing when the caldav-server-tester's own `tests/` package shadowed the caldav project's `tests/test_servers` in `sys.modules` or via the CWD entry in `sys.path`.  The registry is now loaded via `importlib` using the explicit file path, bypassing `sys.path` resolution.
 
 ### Documentation
-- USAGE.md: updated `--format text` section to reflect current multi-line output format and actual support-level values; added `unknown` status
-- USAGE.md: added guide for contributing a new server profile to `caldav/compatibility_hints.py`
-- USAGE.md: added guide for storing checker results in `~/.config/caldav/calendar.conf` (named profile, inline features, and base+overrides patterns)
+*  Updated USAGE.md
+  * `--format text` section to reflect current multi-line output format and actual support-level values; added `unknown` status
+  * added guide for contributing a new server profile to `caldav/compatibility_hints.py`
+  * added guide for storing checker results in `~/.config/caldav/calendar.conf` (named profile, inline features, and base+overrides patterns)
 
 ## [1.0.0] - 2026-03-15
 

src/caldav_server_tester/caldav_server_tester.py

@@ -42,15 +42,44 @@ def _find_caldav_test_registry():
     ]
 
     for root in candidates:
-        if (root / "tests" / "test_servers" / "__init__.py").exists():
-            if str(root) not in sys.path:
-                sys.path.insert(0, str(root))
-            try:
-                from tests.test_servers import get_registry
-
-                return get_registry()
-            except ImportError:
-                pass
+        ts_init = root / "tests" / "test_servers" / "__init__.py"
+        if not ts_init.exists():
+            continue
+        ## Use importlib to load directly from the file path, bypassing
+        ## sys.path resolution entirely.  A plain `from tests.test_servers
+        ## import …` fails when another tests/ directory (e.g. this project's
+        ## own tests/ via CWD or editable install) appears earlier in sys.path.
+        import importlib.util
+
+        tests_spec = importlib.util.spec_from_file_location(
+            "tests",
+            str(root / "tests" / "__init__.py"),
+            submodule_search_locations=[str(root / "tests")],
+        )
+        ts_spec = importlib.util.spec_from_file_location(
+            "tests.test_servers",
+            str(ts_init),
+            submodule_search_locations=[str(ts_init.parent)],
+        )
+        if tests_spec is None or ts_spec is None:
+            continue
+
+        _saved = {k: sys.modules.pop(k) for k in list(sys.modules) if k == "tests" or k.startswith("tests.")}
+        try:
+            tests_mod = importlib.util.module_from_spec(tests_spec)
+            sys.modules["tests"] = tests_mod
+            tests_spec.loader.exec_module(tests_mod)  # type: ignore[union-attr]
+
+            ts_mod = importlib.util.module_from_spec(ts_spec)
+            sys.modules["tests.test_servers"] = ts_mod
+            ts_spec.loader.exec_module(ts_mod)  # type: ignore[union-attr]
+
+            return ts_mod.get_registry()
+        except Exception:
+            for k in list(sys.modules):
+                if k == "tests" or k.startswith("tests."):
+                    del sys.modules[k]
+            sys.modules.update(_saved)
 
     return None
 

tests/test_cli.py

@@ -1,10 +1,15 @@
 """Tests for the CLI (caldav_server_tester.py click application)"""
 
+import sys
+import types
 from unittest.mock import MagicMock, patch
 
 from click.testing import CliRunner
 
-from caldav_server_tester.caldav_server_tester import check_server_compatibility
+from caldav_server_tester.caldav_server_tester import (
+    _find_caldav_test_registry,
+    check_server_compatibility,
+)
 
 
 class TestCliConfigSection:
@@ -135,6 +140,42 @@ def test_name_in_registry_uses_registry(self) -> None:
             )
             mock_check.assert_called_once()
 
+    def test_find_registry_works_when_tests_shadowed_in_sys_modules(self) -> None:
+        """Registry discovery must succeed even when sys.modules['tests'] points elsewhere.
+
+        When the CLI is installed and run, its own tests/ package ends up in
+        sys.modules before _find_caldav_test_registry() runs.  That used to
+        shadow the caldav project's tests/test_servers and cause the function
+        to return None.
+        """
+        # Only meaningful if caldav is checked out as source (has tests/test_servers)
+        from pathlib import Path
+
+        import caldav
+
+        caldav_root = Path(caldav.__file__).parent.parent
+        if not (caldav_root / "tests" / "test_servers" / "__init__.py").exists():
+            return  # skip — caldav is not a source checkout
+
+        # Inject a fake conflicting 'tests' module that has no test_servers attr
+        fake_tests = types.ModuleType("tests")
+        fake_tests.__path__ = ["/some/unrelated/tests"]
+
+        saved_tests = {k: sys.modules.pop(k) for k in list(sys.modules) if k == "tests" or k.startswith("tests.")}
+        sys.modules["tests"] = fake_tests
+        try:
+            registry = _find_caldav_test_registry()
+        finally:
+            for k in list(sys.modules):
+                if k == "tests" or k.startswith("tests."):
+                    del sys.modules[k]
+            sys.modules.update(saved_tests)
+
+        assert registry is not None, (
+            "_find_caldav_test_registry() returned None even though caldav source is available; "
+            "the 'tests' shadowing bug was not fixed"
+        )
+
     def test_name_lookup_is_case_insensitive(self) -> None:
         """--name radicale should match a registry entry named 'Radicale'"""
         runner = CliRunner()