fix _get_classes_from_module

src/umlizer/class_graph.py

@@ -329,25 +329,40 @@ def _get_classes_from_module(module_path: str) -> list[Type[Any]]:
     """
     module_path, module_name = _extract_module_name(module_path)
     original_path = copy.deepcopy(sys.path)
+
+    sys.path.insert(0, module_path)
     try:
-        sys.path.insert(0, module_path)
         module = importlib.import_module(module_name)
-        sys.path = original_path
-        classes_list = [
-            getattr(module, o)
-            for o in dir(module)
-            if inspect.isclass(getattr(module, o)) and not o.startswith('__')
-        ]
-        return classes_list
     except KeyboardInterrupt:
         raise_error('KeyboardInterrupt', 1)
     except Exception as e:
-        print(f' Error loading module {module_name} '.center(80, '='))
+        short_module_path = '.'.join(module_path.split('/')[-3:])
+        print(f' Error loading module {short_module_path} '.center(80, '='))
         print(e)
         print('.' * 80)
         sys.path = original_path
         return []
-    return classes_list
+
+    # If __all__ is defined, get only the classes listed in __all__
+    all_classes_exported = []
+    if hasattr(module, '__all__'):
+        for name in module.__all__:
+            if not inspect.isclass(getattr(module, name)):
+                continue
+            all_classes_exported.append(getattr(module, name))
+
+    # Get all classes defined directly in the module
+    all_classes = []
+    for name in dir(module):
+        if not (
+            inspect.isclass(getattr(module, name))
+            and getattr(getattr(module, name), '__module__', None)
+            == module.__name__
+        ):
+            continue
+        all_classes.append(getattr(module, name))
+    sys.path = original_path
+    return all_classes + all_classes_exported
 
 
 def create_diagram(
@@ -408,7 +423,12 @@ def load_classes_definition(
         raise_error(f'Path "{path_str}" doesn\'t  exist.', 1)
     if os.path.isdir(path_str):
         sys.path.insert(0, path_str)
-        exclude_pattern = [exclude.strip() for exclude in exclude.split(',')]
+        if exclude:
+            exclude_pattern = [
+                exclude.strip() for exclude in exclude.split(',')
+            ]
+        else:
+            exclude_pattern = []
         exclude_pattern.append('__pycache__')
         module_files.extend(
             _search_modules(path_str, exclude_pattern=exclude_pattern)