test(executor): add unit tests for wrap_executor and its helpers

tests/unit/config/test_config.py

@@ -95,13 +95,39 @@ def _reset_live_caches():
     _live_caches.clear()
 
 
+def _reload_fleche_state():
+    """Reload ``fleche.state`` in place, preserving the ``BoundWrapper`` class identity.
+
+    ``importlib.reload`` re-executes the module inside its *existing*
+    ``__dict__``, which is what picks up a monkeypatched config into the
+    module-level ``_CACHE``/``_METADATA`` ContextVars. But it also rebuilds
+    every class defined in the module, including ``BoundWrapper`` — and
+    plenty of code (this test file, ``tests/unit/test_executor.py``, any
+    user code) holds a reference to the *original* class via
+    ``from fleche import BoundWrapper`` or ``from fleche.state import
+    BoundWrapper``, captured once at import time. A second, distinct
+    ``BoundWrapper`` class breaks ``isinstance`` checks (e.g.
+    ``executor.py``'s ``isinstance(func, state.BoundWrapper)``) for every
+    test that runs afterwards, for any reference taken before the reload.
+
+    So: reload, then restore the original class object. Since the module
+    dict is reused in place, the restored class's ``bind`` classmethod still
+    resolves ``_CACHE``/``_METADATA`` to the freshly reloaded ContextVars —
+    only the class *identity* is preserved, not its stale state.
+    """
+    import importlib
+    import fleche.state
+
+    original_bound_wrapper = fleche.state.BoundWrapper
+    importlib.reload(fleche.state)
+    fleche.state.BoundWrapper = original_bound_wrapper
+
+
 @pytest.fixture
 def restore_fleche_state():
     """Reload fleche.state after each test to undo any importlib.reload side effects."""
     yield
-    import importlib
-    import fleche.state
-    importlib.reload(fleche.state)
+    _reload_fleche_state()
 
 
 def test_load_cache_config_default(monkeypatch, config_file):
@@ -220,10 +246,9 @@ def test_cache_default_activates_default_cache(monkeypatch, config_file):
 def test_load_default_metadata(restore_fleche_state, monkeypatch, config_file):
     monkeypatch.setenv("XDG_CONFIG_HOME", config_file)
 
-    import importlib
     import fleche.state
 
-    importlib.reload(fleche.state)
+    _reload_fleche_state()
 
     meta = fleche.state._METADATA.get()
     assert len(meta) == 1
@@ -233,10 +258,9 @@ def test_load_default_metadata(restore_fleche_state, monkeypatch, config_file):
 def test_load_default_cache(restore_fleche_state, monkeypatch, config_file):
     monkeypatch.setenv("XDG_CONFIG_HOME", config_file)
 
-    import importlib
     import fleche.state
 
-    importlib.reload(fleche.state)
+    _reload_fleche_state()
 
     cache_obj = fleche.state._CACHE.get()
     assert isinstance(cache_obj, BaseCache)