Refactor run command and enhance error handling

- Improved 'run' function readability in 'run.py'.
- 'list_files' and 'list_names' now raise ValueError for invalid inputs.
- These functions also raise ValueError when path is not found.
- 'list_names' now directly iterates over returned names.
- Updated test case in 'test_namespace.py' for these changes.

devchat/_cli/run.py

@@ -16,9 +16,9 @@
               help='List all commands in JSON format.')
 @click.option('--recursive', '-r', 'recursive_flag', is_flag=True, default=True,
               help='List all commands recursively.')
-def run(command: str, list_flag: bool, recursive_flag: bool):  
+def run(command: str, list_flag: bool, recursive_flag: bool):
     """
-    Operate workflow engine of DevChat.
+    Operate the workflow engine of DevChat.
     """
     _, _, user_chat_dir = init_dir()
     with handle_errors():
@@ -33,9 +33,8 @@ def run(command: str, list_flag: bool, recursive_flag: bool):
         commander = CommandParser(namespace)
 
         if list_flag:
-            names = namespace.list_names(command, recursive_flag)
             commands = []
-            for name in names:
+            for name in namespace.list_names(command, recursive_flag):
                 cmd = commander.parse(name)
                 if not cmd:
                     logger.warning("Existing command directory failed to parse: %s", name)

devchat/engine/namespace.py

@@ -52,13 +52,13 @@ def get_file(self, name: str, file: str) -> Optional[str]:
         # If no file is found, return None
         return None
 
-    def list_files(self, name: str) -> Optional[List[str]]:
+    def list_files(self, name: str) -> List[str]:
         """
         :param name: The command name in the namespace.
         :return: The full paths of the files in the command directory.
         """
         if not self.is_valid_name(name):
-            return None
+            raise ValueError(f"Invalid name to list files: {name}")
         # Convert the dot-separated name to a path
         path = os.path.join(*name.split('.'))
         files = {}
@@ -70,21 +70,21 @@ def list_files(self, name: str) -> Optional[List[str]]:
                 path_found = True
                 for file in os.listdir(full_path):
                     files[file] = os.path.join(full_path, file)
-        # If no existing path is found, return None
+        # If no existing path is found, raise an error
         if not path_found:
-            return None
+            raise ValueError(f"Path not found to list files: {name}")
         # If path is found but no files exist, return an empty list
         # Sort the files in alphabetical order before returning
         return sorted(files.values()) if files else []
 
-    def list_names(self, name: str = '', recursive: bool = False) -> Optional[List[str]]:
+    def list_names(self, name: str = '', recursive: bool = False) -> List[str]:
         """
         :param name: The command name in the namespace. Defaults to the root.
         :param recursive: Whether to list all descendant names or only child names.
-        :return: A list of all names under the given name, or None if the name is invalid.
+        :return: A list of all names under the given name.
         """
         if not self.is_valid_name(name):
-            return None
+            raise ValueError(f"Invalid name to list names: {name}")
         commands = set()
         path = os.path.join(*name.split('.'))
         found = False
@@ -95,7 +95,9 @@ def list_names(self, name: str = '', recursive: bool = False) -> Optional[List[s
                 self._add_dirnames_to_commands(full_path, name, commands)
                 if recursive:
                     self._add_recursive_dirnames_to_commands(full_path, name, commands)
-        return sorted(commands) if found else None
+        if not found:
+            raise ValueError(f"Path not found to list names: {name}")
+        return sorted(commands)
 
     def _add_dirnames_to_commands(self, full_path: str, name: str, commands: set):
         for dirname in os.listdir(full_path):

tests/test_namespace.py

@@ -83,7 +83,7 @@ def test_list_files(tmp_path):
 
     # Test case 3: a path exists but has no files
     os.makedirs(os.path.join(tmp_path, 'org', 'd', 'e', 'f'), exist_ok=True)
-    assert namespace.list_files('d.e.f') == []
+    assert not namespace.list_files('d.e.f')
 
     # Test case 4: a path that exists in a later branch
     # Create a file in the 'sys' branch