Fix weird state bug around hot reloading modules

Author: FasterSpeeding

tanjun/clients.py

@@ -2697,10 +2697,10 @@ def _reload_module(
         _LOGGER.info("Reloading %s", module_path)
 
         old_loaders = _get_loaders(old_module, module_path)
-        # We assert that the old module has unloaders early to avoid unnecessarily
-        # importing the new module.
-        if not any(loader.has_unload for loader in old_loaders):
-            raise errors.ModuleMissingUnloaders(f"Didn't find any unloaders in old {module_path}", module_path)
+        modules_dict.pop(module_path)
+        with _WrapLoadError(errors.FailedModuleUnload, module_path):
+            # This will never raise MissingLoaders as we assert this earlier
+            self._call_unloaders(module_path, old_loaders)
 
         module = yield load_module
 
@@ -2711,10 +2711,6 @@ def _reload_module(
         if not any(loader.has_load for loader in loaders):
             raise errors.ModuleMissingLoaders(f"Didn't find any loaders in new {module_path}", module_path)
 
-        with _WrapLoadError(errors.FailedModuleUnload, module_path):
-            # This will never raise MissingLoaders as we assert this earlier
-            self._call_unloaders(module_path, old_loaders)
-
         try:
             # This will never raise MissingLoaders as we assert this earlier
             self._call_loaders(module_path, loaders)