test_question_cmd: modified tests to use '.msg' file suffix

- no longer using file suffix to choose the format
- added 'mformat' argument to 'write_xxx()' functions
- file suffix is now set by 'Message.to_file()' per default

chatmastermind/ai_factory.py

@@ -3,18 +3,20 @@ Creates different AI instances, based on the given configuration.
 """
 
 import argparse
-from typing import cast
+from typing import cast, Optional
 from .configuration import Config, AIConfig, OpenAIConfig
 from .ai import AI, AIError
 from .ais.openai import OpenAI
 
 
-def create_ai(args: argparse.Namespace, config: Config) -> AI:  # noqa: 11
+def create_ai(args: argparse.Namespace, config: Config,  # noqa: 11
+              def_ai: Optional[str] = None,
+              def_model: Optional[str] = None) -> AI:
     """
-    Creates an AI subclass instance from the given arguments
-    and configuration file. If AI has not been set in the
-    arguments, it searches for the ID 'default'. If that
-    is not found, it uses the first AI in the list.
+    Creates an AI subclass instance from the given arguments and configuration file.
+    If AI has not been set in the arguments, it searches for the ID 'default'. If
+    that is not found, it uses the first AI in the list. It's also possible to
+    specify a default AI and model using 'def_ai' and 'def_model'.
     """
     ai_conf: AIConfig
     if hasattr(args, 'AI') and args.AI:
@@ -22,6 +24,8 @@ def create_ai(args: argparse.Namespace, config: Config) -> AI:  # noqa: 11
             ai_conf = config.ais[args.AI]
         except KeyError:
             raise AIError(f"AI ID '{args.AI}' does not exist in this configuration")
+    elif def_ai:
+        ai_conf = config.ais[def_ai]
     elif 'default' in config.ais:
         ai_conf = config.ais['default']
     else:
@@ -34,6 +38,8 @@ def create_ai(args: argparse.Namespace, config: Config) -> AI:  # noqa: 11
         ai = OpenAI(cast(OpenAIConfig, ai_conf))
         if hasattr(args, 'model') and args.model:
             ai.config.model = args.model
+        elif def_model:
+            ai.config.model = def_model
         if hasattr(args, 'max_tokens') and args.max_tokens:
             ai.config.max_tokens = args.max_tokens
         if hasattr(args, 'temperature') and args.temperature:

chatmastermind/ais/openai.py

@@ -44,7 +44,7 @@ class OpenAI(AI):
             frequency_penalty=self.config.frequency_penalty,
             presence_penalty=self.config.presence_penalty)
         question.answer = Answer(response['choices'][0]['message']['content'])
-        question.tags = otags
+        question.tags = set(otags) if otags is not None else None
         question.ai = self.ID
         question.model = self.config.model
         answers: list[Message] = [question]

chatmastermind/chat.py

@@ -6,9 +6,9 @@ from pathlib import Path
 from pprint import PrettyPrinter
 from pydoc import pager
 from dataclasses import dataclass
-from typing import TypeVar, Type, Optional, ClassVar, Any, Callable, Literal, Union
+from typing import TypeVar, Type, Optional, Any, Callable, Literal, Union
 from .configuration import default_config_file
-from .message import Message, MessageFilter, MessageError, message_in
+from .message import Message, MessageFilter, MessageError, MessageFormat, message_in
 from .tags import Tag
 
 ChatInst = TypeVar('ChatInst', bound='Chat')
@@ -17,6 +17,7 @@ ChatDBInst = TypeVar('ChatDBInst', bound='ChatDB')
 db_next_file = '.next'
 ignored_files = [db_next_file, default_config_file]
 msg_location = Literal['mem', 'disk', 'cache', 'db', 'all']
+msg_suffix = Message.file_suffix_write
 
 
 class ChatError(Exception):
@@ -52,7 +53,7 @@ def read_dir(dir_path: Path,
     for file_path in sorted(file_iter):
         if (file_path.is_file()
            and file_path.name not in ignored_files  # noqa: W503
-           and file_path.suffix in Message.file_suffixes):  # noqa: W503
+           and file_path.suffix in Message.file_suffixes_read):  # noqa: W503
             try:
                 message = Message.from_file(file_path, mfilter)
                 if message:
@@ -63,22 +64,20 @@ def read_dir(dir_path: Path,
 
 
 def make_file_path(dir_path: Path,
-                   file_suffix: str,
                    next_fid: Callable[[], int]) -> Path:
     """
-    Create a file_path for the given directory using the
-    given file_suffix and ID generator function.
+    Create a file_path for the given directory using the given ID generator function.
     """
-    file_path = dir_path / f"{next_fid():04d}{file_suffix}"
+    file_path = dir_path / f"{next_fid():04d}{msg_suffix}"
     while file_path.exists():
-        file_path = dir_path / f"{next_fid():04d}{file_suffix}"
+        file_path = dir_path / f"{next_fid():04d}{msg_suffix}"
     return file_path
 
 
 def write_dir(dir_path: Path,
               messages: list[Message],
-              file_suffix: str,
-              next_fid: Callable[[], int]) -> None:
+              next_fid: Callable[[], int],
+              mformat: MessageFormat = Message.default_format) -> None:
     """
     Write all messages to the given directory. If a message has no file_path,
     a new one will be created. If message.file_path exists, it will be modified
@@ -86,18 +85,17 @@ def write_dir(dir_path: Path,
     Parameters:
     * 'dir_path': destination directory
     * 'messages': list of messages to write
-    * 'file_suffix': suffix for the message files ['.txt'|'.yaml']
     * 'next_fid': callable that returns the next file ID
     """
     for message in messages:
         file_path = message.file_path
         # message has no file_path: create one
         if not file_path:
-            file_path = make_file_path(dir_path, file_suffix, next_fid)
+            file_path = make_file_path(dir_path, next_fid)
         # file_path does not point to given directory: modify it
         elif not file_path.parent.samefile(dir_path):
             file_path = dir_path / file_path.name
-        message.to_file(file_path)
+        message.to_file(file_path, mformat=mformat)
 
 
 def clear_dir(dir_path: Path,
@@ -109,7 +107,7 @@ def clear_dir(dir_path: Path,
     for file_path in file_iter:
         if (file_path.is_file()
            and file_path.name not in ignored_files  # noqa: W503
-           and file_path.suffix in Message.file_suffixes):  # noqa: W503
+           and file_path.suffix in Message.file_suffixes_read):  # noqa: W503
             file_path.unlink(missing_ok=True)
 
 
@@ -146,7 +144,7 @@ class Chat:
         Matching is True if:
         * 'name' matches the full 'file_path'
         * 'name' matches 'file_path.name' (i. e. including the suffix)
-        * 'name' matches 'file_path.stem' (i. e. without a suffix)
+        * 'name' matches 'file_path.stem' (i. e. without the suffix)
         """
         return Path(name) == file_path or name == file_path.name or name == file_path.stem
 
@@ -281,13 +279,10 @@ class ChatDB(Chat):
     persistently.
     """
 
-    default_file_suffix: ClassVar[str] = '.txt'
-
     cache_path: Path
     db_path: Path
     # a MessageFilter that all messages must match (if given)
     mfilter: Optional[MessageFilter] = None
-    file_suffix: str = default_file_suffix
     # the glob pattern for all messages
     glob: Optional[str] = None
 
@@ -317,8 +312,7 @@ class ChatDB(Chat):
           when reading them.
         """
         messages = read_dir(db_path, glob, mfilter)
-        return cls(messages, cache_path, db_path, mfilter,
-                   cls.default_file_suffix, glob)
+        return cls(messages, cache_path, db_path, mfilter, glob)
 
     @classmethod
     def from_messages(cls: Type[ChatDBInst],
@@ -345,7 +339,9 @@ class ChatDB(Chat):
         with open(self.next_path, 'w') as f:
             f.write(f'{fid}')
 
-    def msg_write(self, messages: Optional[list[Message]] = None) -> None:
+    def msg_write(self,
+                  messages: Optional[list[Message]] = None,
+                  mformat: MessageFormat = Message.default_format) -> None:
         """
         Write either the given messages or the internal ones to their CURRENT file_path.
         If messages are given, they all must have a valid file_path. When writing the
@@ -356,7 +352,7 @@ class ChatDB(Chat):
             raise ChatError("Can't write files without a valid file_path")
         msgs = iter(messages if messages else self.messages)
         while (m := next(msgs, None)):
-            m.to_file()
+            m.to_file(mformat=mformat)
 
     def msg_update(self, messages: list[Message], write: bool = True) -> None:
         """
@@ -518,7 +514,6 @@ class ChatDB(Chat):
         """
         write_dir(self.cache_path,
                   messages if messages else self.messages,
-                  self.file_suffix,
                   self.get_next_fid)
 
     def cache_add(self, messages: list[Message], write: bool = True) -> None:
@@ -531,11 +526,10 @@ class ChatDB(Chat):
         if write:
             write_dir(self.cache_path,
                       messages,
-                      self.file_suffix,
                       self.get_next_fid)
         else:
             for m in messages:
-                m.file_path = make_file_path(self.cache_path, self.default_file_suffix, self.get_next_fid)
+                m.file_path = make_file_path(self.cache_path, self.get_next_fid)
         self.messages += messages
         self.msg_sort()
 
@@ -585,7 +579,6 @@ class ChatDB(Chat):
         """
         write_dir(self.db_path,
                   messages if messages else self.messages,
-                  self.file_suffix,
                   self.get_next_fid)
 
     def db_add(self, messages: list[Message], write: bool = True) -> None:
@@ -598,11 +591,10 @@ class ChatDB(Chat):
         if write:
             write_dir(self.db_path,
                       messages,
-                      self.file_suffix,
                       self.get_next_fid)
         else:
             for m in messages:
-                m.file_path = make_file_path(self.db_path, self.default_file_suffix, self.get_next_fid)
+                m.file_path = make_file_path(self.db_path, self.get_next_fid)
         self.messages += messages
         self.msg_sort()
 

chatmastermind/commands/question.py

@@ -2,6 +2,7 @@ import sys
 import argparse
 from pathlib import Path
 from itertools import zip_longest
+from copy import deepcopy
 from ..configuration import Config
 from ..chat import ChatDB
 from ..message import Message, MessageFilter, MessageError, Question, source_code
@@ -105,13 +106,75 @@ def make_request(ai: AI, chat: ChatDB, message: Message, args: argparse.Namespac
         print(response.tokens)
 
 
+def create_msg_args(msg: Message, args: argparse.Namespace) -> argparse.Namespace:
+    """
+    Takes an existing message and CLI arguments, and returns modified args based
+    on the members of the given message. Used e.g. when repeating messages, where
+    it's necessary to determine the correct AI, module and output tags to use
+    (either from the existing message or the given args).
+    """
+    msg_args = args
+    # if AI, model or output tags have not been specified,
+    # use those from the original message
+    if (args.AI is None
+       or args.model is None  # noqa: W503
+       or args.output_tags is None):  # noqa: W503
+        msg_args = deepcopy(args)
+        if args.AI is None and msg.ai is not None:
+            msg_args.AI = msg.ai
+        if args.model is None and msg.model is not None:
+            msg_args.model = msg.model
+        if args.output_tags is None and msg.tags is not None:
+            msg_args.output_tags = msg.tags
+    return msg_args
+
+
+def repeat_messages(messages: list[Message], chat: ChatDB, args: argparse.Namespace, config: Config) -> None:
+    """
+    Repeat the given messages using the given arguments.
+    """
+    ai: AI
+    for msg in messages:
+        msg_args = create_msg_args(msg, args)
+        ai = create_ai(msg_args, config)
+        print(f"--------- Repeating message '{msg.msg_id()}': ---------")
+        # overwrite the latest message if requested or empty
+        # -> but not if it's in the DB!
+        if ((msg.answer is None or msg_args.overwrite is True)
+           and (not chat.msg_in_db(msg))):  # noqa: W503
+            msg.clear_answer()
+            make_request(ai, chat, msg, msg_args)
+        # otherwise create a new one
+        else:
+            msg_args.ask = [msg.question]
+            message = create_message(chat, msg_args)
+            make_request(ai, chat, message, msg_args)
+
+
+def invert_input_tag_args(args: argparse.Namespace) -> None:
+    """
+    Changes the semantics of the INPUT tags for this command:
+    * not tags specified on the CLI -> no tags are selected
+    * empty tags specified on the CLI -> all tags are selected
+    """
+    if args.or_tags is None:
+        args.or_tags = set()
+    elif len(args.or_tags) == 0:
+        args.or_tags = None
+    if args.and_tags is None:
+        args.and_tags = set()
+    elif len(args.and_tags) == 0:
+        args.and_tags = None
+
+
 def question_cmd(args: argparse.Namespace, config: Config) -> None:
     """
     Handler for the 'question' command.
     """
-    mfilter = MessageFilter(tags_or=args.or_tags if args.or_tags is not None else set(),
-                            tags_and=args.and_tags if args.and_tags is not None else set(),
-                            tags_not=args.exclude_tags if args.exclude_tags is not None else set())
+    invert_input_tag_args(args)
+    mfilter = MessageFilter(tags_or=args.or_tags,
+                            tags_and=args.and_tags,
+                            tags_not=args.exclude_tags)
     chat = ChatDB.from_dir(cache_path=Path(config.cache),
                            db_path=Path(config.db),
                            mfilter=mfilter)
@@ -121,30 +184,24 @@ def question_cmd(args: argparse.Namespace, config: Config) -> None:
     if args.create:
         return
 
-    # create the correct AI instance
-    ai: AI = create_ai(args, config)
-
     # === ASK ===
     if args.ask:
+        ai: AI = create_ai(args, config)
         make_request(ai, chat, message, args)
     # === REPEAT ===
     elif args.repeat is not None:
+        repeat_msgs: list[Message] = []
+        # repeat latest message
+        if len(args.repeat) == 0:
             lmessage = chat.msg_latest(loc='cache')
             if lmessage is None:
                 print("No message found to repeat!")
                 sys.exit(1)
+            repeat_msgs.append(lmessage)
+        # repeat given message(s)
         else:
-            print(f"Repeating message '{lmessage.msg_id()}':")
-        # overwrite the latest message if requested or empty
-        if lmessage.answer is None or args.overwrite is True:
-            lmessage.clear_answer()
-            make_request(ai, chat, lmessage, args)
-        # otherwise create a new one
-        else:
-            args.ask = [lmessage.question]
-            message = create_message(chat, args)
-            make_request(ai, chat, message, args)
-
+            repeat_msgs = chat.msg_find(args.repeat, loc='disk')
+        repeat_messages(repeat_msgs, chat, args, config)
     # === PROCESS ===
     elif args.process is not None:
         # TODO: process either all questions without an

chatmastermind/main.py

@@ -34,13 +34,13 @@ def create_parser() -> argparse.ArgumentParser:
 
     # a parent parser for all commands that support tag selection
     tag_parser = argparse.ArgumentParser(add_help=False)
-    tag_arg = tag_parser.add_argument('-t', '--or-tags', nargs='+',
+    tag_arg = tag_parser.add_argument('-t', '--or-tags', nargs='*',
                                       help='List of tags (one must match)', metavar='OTAGS')
     tag_arg.completer = tags_completer  # type: ignore
-    atag_arg = tag_parser.add_argument('-k', '--and-tags', nargs='+',
+    atag_arg = tag_parser.add_argument('-k', '--and-tags', nargs='*',
                                        help='List of tags (all must match)', metavar='ATAGS')
     atag_arg.completer = tags_completer  # type: ignore
-    etag_arg = tag_parser.add_argument('-x', '--exclude-tags', nargs='+',
+    etag_arg = tag_parser.add_argument('-x', '--exclude-tags', nargs='*',
                                        help='List of tags to exclude', metavar='XTAGS')
     etag_arg.completer = tags_completer  # type: ignore
     otag_arg = tag_parser.add_argument('-o', '--output-tags', nargs='+',

chatmastermind/message.py

@@ -5,7 +5,8 @@ import pathlib
 import yaml
 import tempfile
 import shutil
-from typing import Type, TypeVar, ClassVar, Optional, Any, Union, Final, Literal, Iterable
+from typing import Type, TypeVar, ClassVar, Optional, Any, Union, Final, Literal, Iterable, Tuple
+from typing import get_args as typing_get_args
 from dataclasses import dataclass, asdict, field
 from .tags import Tag, TagLine, TagError, match_tags, rename_tags
 
@@ -15,6 +16,9 @@ MessageInst = TypeVar('MessageInst', bound='Message')
 AILineInst = TypeVar('AILineInst', bound='AILine')
 ModelLineInst = TypeVar('ModelLineInst', bound='ModelLine')
 YamlDict = dict[str, Union[QuestionInst, AnswerInst, set[Tag]]]
+MessageFormat = Literal['txt', 'yaml']
+message_valid_formats: Final[Tuple[MessageFormat, ...]] = typing_get_args(MessageFormat)
+message_default_format: Final[MessageFormat] = 'txt'
 
 
 class MessageError(Exception):
@@ -92,7 +96,7 @@ class MessageFilter:
 
 class AILine(str):
     """
-    A line that represents the AI name in a '.txt' file..
+    A line that represents the AI name in the 'txt' format.
     """
     prefix: Final[str] = 'AI:'
 
@@ -112,7 +116,7 @@ class AILine(str):
 
 class ModelLine(str):
     """
-    A line that represents the model name in a '.txt' file..
+    A line that represents the model name in the 'txt' format.
     """
     prefix: Final[str] = 'MODEL:'
 
@@ -216,7 +220,9 @@ class Message():
     model: Optional[str] = field(default=None, compare=False)
     file_path: Optional[pathlib.Path] = field(default=None, compare=False)
     # class variables
-    file_suffixes: ClassVar[list[str]] = ['.txt', '.yaml']
+    file_suffixes_read: ClassVar[list[str]] = ['.msg', '.txt', '.yaml']
+    file_suffix_write: ClassVar[str] = '.msg'
+    default_format: ClassVar[MessageFormat] = message_default_format
     tags_yaml_key: ClassVar[str] = 'tags'
     file_yaml_key: ClassVar[str] = 'file_path'
     ai_yaml_key: ClassVar[str] = 'ai'
@@ -276,16 +282,8 @@ class Message():
         tags: set[Tag] = set()
         if not file_path.exists():
             raise MessageError(f"Message file '{file_path}' does not exist")
-        if file_path.suffix not in cls.file_suffixes:
+        if file_path.suffix not in cls.file_suffixes_read:
             raise MessageError(f"File type '{file_path.suffix}' is not supported")
-        # for TXT, it's enough to read the TagLine
-        if file_path.suffix == '.txt':
-            with open(file_path, "r") as fd:
-                try:
-                    tags = TagLine(fd.readline()).tags(prefix, contain)
-                except TagError:
-                    pass  # message without tags
-        else:  # '.yaml'
         try:
             message = cls.from_file(file_path)
             if message:
@@ -328,15 +326,16 @@ class Message():
         """
         if not file_path.exists():
             raise MessageError(f"Message file '{file_path}' does not exist")
-        if file_path.suffix not in cls.file_suffixes:
+        if file_path.suffix not in cls.file_suffixes_read:
             raise MessageError(f"File type '{file_path.suffix}' is not supported")
-
-        if file_path.suffix == '.txt':
+        # try TXT first
+        try:
             message = cls.__from_file_txt(file_path,
                                           mfilter.tags_or if mfilter else None,
                                           mfilter.tags_and if mfilter else None,
                                           mfilter.tags_not if mfilter else None)
-        else:
+        # then YAML
+        except MessageError:
             message = cls.__from_file_yaml(file_path)
         if message and (mfilter is None or message.match(mfilter)):
             return message
@@ -373,10 +372,6 @@ class Message():
                 tags = TagLine(fd.readline()).tags()
             except TagError:
                 fd.seek(pos)
-            if tags_or or tags_and or tags_not:
-                # match with an empty set if the file has no tags
-                if not match_tags(tags, tags_or, tags_and, tags_not):
-                    return None
             # AILine (Optional)
             try:
                 pos = fd.tell()
@@ -401,6 +396,12 @@ class Message():
             answer = Answer.from_list(text[answer_idx + 1:])
         except ValueError:
             question = Question.from_list(text[question_idx:])
+        # match tags AFTER reading the whole file
+        # -> make sure it's a valid 'txt' file format
+        if tags_or or tags_and or tags_not:
+            # match with an empty set if the file has no tags
+            if not match_tags(tags, tags_or, tags_and, tags_not):
+                return None
         return cls(question, answer, tags, ai, model, file_path)
 
     @classmethod
@@ -442,21 +443,29 @@ class Message():
             output.append(self.answer)
         return '\n'.join(output)
 
-    def to_file(self, file_path: Optional[pathlib.Path]=None) -> None:  # noqa: 11
+    def to_file(self, file_path: Optional[pathlib.Path]=None, mformat: MessageFormat = message_default_format) -> None:  # noqa: 11
         """
-        Write a Message to the given file. Type is determined based on the suffix.
-        Currently supported suffixes: ['.txt', '.yaml']
+        Write a Message to the given file. Supported message file formats are 'txt' and 'yaml'.
+        Suffix is always '.msg'.
         """
         if file_path:
             self.file_path = file_path
         if not self.file_path:
             raise MessageError("Got no valid path to write message")
-        if self.file_path.suffix not in self.file_suffixes:
-            raise MessageError(f"File type '{self.file_path.suffix}' is not supported")
+        if mformat not in message_valid_formats:
+            raise MessageError(f"File format '{mformat}' is not supported")
+        # check for valid suffix
+        # -> add one if it's empty
+        # -> refuse old or otherwise unsupported suffixes
+        if not self.file_path.suffix:
+            self.file_path = self.file_path.with_suffix(self.file_suffix_write)
+        elif self.file_path.suffix != self.file_suffix_write:
+            raise MessageError(f"File suffix '{self.file_path.suffix}' is not supported")
         # TXT
-        if self.file_path.suffix == '.txt':
+        if mformat == 'txt':
             return self.__to_file_txt(self.file_path)
-        elif self.file_path.suffix == '.yaml':
+        # YAML
+        elif mformat == 'yaml':
             return self.__to_file_yaml(self.file_path)
 
     def __to_file_txt(self, file_path: pathlib.Path) -> None:
@@ -468,8 +477,8 @@ class Message():
             * Model [Optional]
             * Question.txt_header
             * Question
-            * Answer.txt_header
-            * Answer
+            * Answer.txt_header [Optional]
+            * Answer [Optional]
         """
         with tempfile.NamedTemporaryFile(dir=file_path.parent, prefix=file_path.name, mode="w", delete=False) as temp_fd:
             temp_file_path = pathlib.Path(temp_fd.name)

tests/test_chat.py

@@ -10,6 +10,20 @@ from chatmastermind.message import Message, Question, Answer, Tag, MessageFilter
 from chatmastermind.chat import Chat, ChatDB, ChatError
 
 
+msg_suffix: str = Message.file_suffix_write
+
+
+def msg_to_file_force_suffix(msg: Message) -> None:
+    """
+    Force writing a message file with illegal suffixes.
+    """
+    def_suffix = Message.file_suffix_write
+    assert msg.file_path
+    Message.file_suffix_write = msg.file_path.suffix
+    msg.to_file()
+    Message.file_suffix_write = def_suffix
+
+
 class TestChatBase(unittest.TestCase):
     def assert_messages_equal(self, msg1: list[Message], msg2: list[Message]) -> None:
         """
@@ -27,11 +41,11 @@ class TestChat(TestChatBase):
         self.message1 = Message(Question('Question 1'),
                                 Answer('Answer 1'),
                                 {Tag('atag1'), Tag('btag2')},
-                                file_path=pathlib.Path('0001.txt'))
+                                file_path=pathlib.Path(f'0001{msg_suffix}'))
         self.message2 = Message(Question('Question 2'),
                                 Answer('Answer 2'),
                                 {Tag('btag2')},
-                                file_path=pathlib.Path('0002.txt'))
+                                file_path=pathlib.Path(f'0002{msg_suffix}'))
         self.maxDiff = None
 
     def test_unique_id(self) -> None:
@@ -99,24 +113,24 @@ class TestChat(TestChatBase):
 
     def test_find_remove_messages(self) -> None:
         self.chat.msg_add([self.message1, self.message2])
-        msgs = self.chat.msg_find(['0001.txt'])
+        msgs = self.chat.msg_find(['0001'])
         self.assertListEqual(msgs, [self.message1])
-        msgs = self.chat.msg_find(['0001.txt', '0002.txt'])
+        msgs = self.chat.msg_find(['0001', '0002'])
         self.assertListEqual(msgs, [self.message1, self.message2])
         # add new Message with full path
         message3 = Message(Question('Question 2'),
                            Answer('Answer 2'),
                            {Tag('btag2')},
-                           file_path=pathlib.Path('/foo/bla/0003.txt'))
+                           file_path=pathlib.Path(f'/foo/bla/0003{msg_suffix}'))
         self.chat.msg_add([message3])
         # find new Message by full path
-        msgs = self.chat.msg_find(['/foo/bla/0003.txt'])
+        msgs = self.chat.msg_find([f'/foo/bla/0003{msg_suffix}'])
         self.assertListEqual(msgs, [message3])
         # find Message with full path only by filename
-        msgs = self.chat.msg_find(['0003.txt'])
+        msgs = self.chat.msg_find([f'0003{msg_suffix}'])
         self.assertListEqual(msgs, [message3])
         # remove last message
-        self.chat.msg_remove(['0003.txt'])
+        self.chat.msg_remove(['0003'])
         self.assertListEqual(self.chat.messages, [self.message1, self.message2])
 
     def test_latest_message(self) -> None:
@@ -146,13 +160,13 @@ Answer 2
         self.chat.msg_add([self.message1, self.message2])
         self.chat.print(paged=False, with_tags=True, with_files=True)
         expected_output = f"""{TagLine.prefix} atag1 btag2
-FILE: 0001.txt
+FILE: 0001{msg_suffix}
 {Question.txt_header}
 Question 1
 {Answer.txt_header}
 Answer 1
 {TagLine.prefix} btag2
-FILE: 0002.txt
+FILE: 0002{msg_suffix}
 {Question.txt_header}
 Question 2
 {Answer.txt_header}
@@ -168,31 +182,27 @@ class TestChatDB(TestChatBase):
 
         self.message1 = Message(Question('Question 1'),
                                 Answer('Answer 1'),
-                                {Tag('tag1')},
-                                file_path=pathlib.Path('0001.txt'))
+                                {Tag('tag1')})
         self.message2 = Message(Question('Question 2'),
                                 Answer('Answer 2'),
-                                {Tag('tag2')},
-                                file_path=pathlib.Path('0002.yaml'))
+                                {Tag('tag2')})
         self.message3 = Message(Question('Question 3'),
                                 Answer('Answer 3'),
-                                {Tag('tag3')},
-                                file_path=pathlib.Path('0003.txt'))
+                                {Tag('tag3')})
         self.message4 = Message(Question('Question 4'),
                                 Answer('Answer 4'),
-                                {Tag('tag4')},
-                                file_path=pathlib.Path('0004.yaml'))
+                                {Tag('tag4')})
 
-        self.message1.to_file(pathlib.Path(self.db_path.name, '0001.txt'))
-        self.message2.to_file(pathlib.Path(self.db_path.name, '0002.yaml'))
-        self.message3.to_file(pathlib.Path(self.db_path.name, '0003.txt'))
-        self.message4.to_file(pathlib.Path(self.db_path.name, '0004.yaml'))
+        self.message1.to_file(pathlib.Path(self.db_path.name, '0001'), mformat='txt')
+        self.message2.to_file(pathlib.Path(self.db_path.name, '0002'), mformat='yaml')
+        self.message3.to_file(pathlib.Path(self.db_path.name, '0003'), mformat='txt')
+        self.message4.to_file(pathlib.Path(self.db_path.name, '0004'), mformat='yaml')
         # make the next FID match the current state
         next_fname = pathlib.Path(self.db_path.name) / '.next'
         with open(next_fname, 'w') as f:
             f.write('4')
         # add some "trash" in order to test if it's correctly handled / ignored
-        self.trash_files = ['.config.yaml', 'foo.yaml', 'bla.txt']
+        self.trash_files = ['.config.yaml', 'foo.yaml', 'bla.txt', 'fubar.msg']
         for file in self.trash_files:
             with open(pathlib.Path(self.db_path.name) / file, 'w') as f:
                 f.write('test trash')
@@ -207,7 +217,7 @@ class TestChatDB(TestChatBase):
         List all Message files in the given TemporaryDirectory.
         """
         # exclude '.next'
-        return [f for f in pathlib.Path(tmp_dir.name).glob('*.[ty]*') if f.name not in self.trash_files]
+        return [f for f in pathlib.Path(tmp_dir.name).glob('*.[tym]*') if f.name not in self.trash_files]
 
     def tearDown(self) -> None:
         self.db_path.cleanup()
@@ -218,13 +228,31 @@ class TestChatDB(TestChatBase):
         duplicate_message = Message(Question('Question 4'),
                                     Answer('Answer 4'),
                                     {Tag('tag4')},
-                                    file_path=pathlib.Path('0004.txt'))
-        duplicate_message.to_file(pathlib.Path(self.db_path.name, '0004.txt'))
+                                    file_path=pathlib.Path(self.db_path.name, '0004.txt'))
+        msg_to_file_force_suffix(duplicate_message)
         with self.assertRaises(ChatError) as cm:
             ChatDB.from_dir(pathlib.Path(self.cache_path.name),
                             pathlib.Path(self.db_path.name))
         self.assertEqual(str(cm.exception), "Validation failed")
 
+    def test_file_path_ID_exists(self) -> None:
+        """
+        Tests if the CacheDB chooses another ID if a file path with
+        the given one exists.
+        """
+        # create a new and empty CacheDB
+        db_path = tempfile.TemporaryDirectory()
+        cache_path = tempfile.TemporaryDirectory()
+        chat_db = ChatDB.from_dir(pathlib.Path(cache_path.name),
+                                  pathlib.Path(db_path.name))
+        # add a message file
+        message = Message(Question('What?'),
+                          file_path=pathlib.Path(cache_path.name) / f'0001{msg_suffix}')
+        message.to_file()
+        message1 = Message(Question('Where?'))
+        chat_db.cache_write([message1])
+        self.assertEqual(message1.msg_id(), '0002')
+
     def test_from_dir(self) -> None:
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
                                   pathlib.Path(self.db_path.name))
@@ -233,25 +261,23 @@ class TestChatDB(TestChatBase):
         self.assertEqual(chat_db.db_path, pathlib.Path(self.db_path.name))
         # check that the files are sorted
         self.assertEqual(chat_db.messages[0].file_path,
-                         pathlib.Path(self.db_path.name, '0001.txt'))
+                         pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
         self.assertEqual(chat_db.messages[1].file_path,
-                         pathlib.Path(self.db_path.name, '0002.yaml'))
+                         pathlib.Path(self.db_path.name, f'0002{msg_suffix}'))
         self.assertEqual(chat_db.messages[2].file_path,
-                         pathlib.Path(self.db_path.name, '0003.txt'))
+                         pathlib.Path(self.db_path.name, f'0003{msg_suffix}'))
         self.assertEqual(chat_db.messages[3].file_path,
-                         pathlib.Path(self.db_path.name, '0004.yaml'))
+                         pathlib.Path(self.db_path.name, f'0004{msg_suffix}'))
 
     def test_from_dir_glob(self) -> None:
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
                                   pathlib.Path(self.db_path.name),
-                                  glob='*.txt')
-        self.assertEqual(len(chat_db.messages), 2)
+                                  glob='*1.*')
+        self.assertEqual(len(chat_db.messages), 1)
         self.assertEqual(chat_db.cache_path, pathlib.Path(self.cache_path.name))
         self.assertEqual(chat_db.db_path, pathlib.Path(self.db_path.name))
         self.assertEqual(chat_db.messages[0].file_path,
-                         pathlib.Path(self.db_path.name, '0001.txt'))
-        self.assertEqual(chat_db.messages[1].file_path,
-                         pathlib.Path(self.db_path.name, '0003.txt'))
+                         pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
 
     def test_from_dir_filter_tags(self) -> None:
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
@@ -261,7 +287,7 @@ class TestChatDB(TestChatBase):
         self.assertEqual(chat_db.cache_path, pathlib.Path(self.cache_path.name))
         self.assertEqual(chat_db.db_path, pathlib.Path(self.db_path.name))
         self.assertEqual(chat_db.messages[0].file_path,
-                         pathlib.Path(self.db_path.name, '0001.txt'))
+                         pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
 
     def test_from_dir_filter_tags_empty(self) -> None:
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
@@ -279,7 +305,7 @@ class TestChatDB(TestChatBase):
         self.assertEqual(chat_db.cache_path, pathlib.Path(self.cache_path.name))
         self.assertEqual(chat_db.db_path, pathlib.Path(self.db_path.name))
         self.assertEqual(chat_db.messages[0].file_path,
-                         pathlib.Path(self.db_path.name, '0002.yaml'))
+                         pathlib.Path(self.db_path.name, f'0002{msg_suffix}'))
         self.assertEqual(chat_db.messages[0].answer, 'Answer 2')
 
     def test_from_messages(self) -> None:
@@ -324,25 +350,25 @@ class TestChatDB(TestChatBase):
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
                                   pathlib.Path(self.db_path.name))
         # check that Message.file_path is correct
-        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, '0001.txt'))
-        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, '0002.yaml'))
-        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, '0003.txt'))
-        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, '0004.yaml'))
+        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
+        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, f'0002{msg_suffix}'))
+        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, f'0003{msg_suffix}'))
+        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, f'0004{msg_suffix}'))
 
         # write the messages to the cache directory
         chat_db.cache_write()
         # check if the written files are in the cache directory
         cache_dir_files = self.message_list(self.cache_path)
         self.assertEqual(len(cache_dir_files), 4)
-        self.assertIn(pathlib.Path(self.cache_path.name, '0001.txt'), cache_dir_files)
-        self.assertIn(pathlib.Path(self.cache_path.name, '0002.yaml'), cache_dir_files)
-        self.assertIn(pathlib.Path(self.cache_path.name, '0003.txt'), cache_dir_files)
-        self.assertIn(pathlib.Path(self.cache_path.name, '0004.yaml'), cache_dir_files)
+        self.assertIn(pathlib.Path(self.cache_path.name, f'0001{msg_suffix}'), cache_dir_files)
+        self.assertIn(pathlib.Path(self.cache_path.name, f'0002{msg_suffix}'), cache_dir_files)
+        self.assertIn(pathlib.Path(self.cache_path.name, f'0003{msg_suffix}'), cache_dir_files)
+        self.assertIn(pathlib.Path(self.cache_path.name, f'0004{msg_suffix}'), cache_dir_files)
         # check that Message.file_path has been correctly updated
-        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.cache_path.name, '0001.txt'))
-        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.cache_path.name, '0002.yaml'))
-        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.cache_path.name, '0003.txt'))
-        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.cache_path.name, '0004.yaml'))
+        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.cache_path.name, f'0001{msg_suffix}'))
+        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.cache_path.name, f'0002{msg_suffix}'))
+        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.cache_path.name, f'0003{msg_suffix}'))
+        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.cache_path.name, f'0004{msg_suffix}'))
 
         # check the timestamp of the files in the DB directory
         db_dir_files = self.message_list(self.db_path)
@@ -354,18 +380,18 @@ class TestChatDB(TestChatBase):
         # check if the written files are in the DB directory
         db_dir_files = self.message_list(self.db_path)
         self.assertEqual(len(db_dir_files), 4)
-        self.assertIn(pathlib.Path(self.db_path.name, '0001.txt'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0002.yaml'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0003.txt'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0004.yaml'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0001{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0002{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0003{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0004{msg_suffix}'), db_dir_files)
         # check if all files in the DB dir have actually been overwritten
         for file in db_dir_files:
             self.assertGreater(file.stat().st_mtime, old_timestamps[file])
         # check that Message.file_path has been correctly updated (again)
-        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, '0001.txt'))
-        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, '0002.yaml'))
-        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, '0003.txt'))
-        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, '0004.yaml'))
+        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
+        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, f'0002{msg_suffix}'))
+        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, f'0003{msg_suffix}'))
+        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, f'0004{msg_suffix}'))
 
     def test_db_read(self) -> None:
         # create a new ChatDB instance
@@ -380,65 +406,65 @@ class TestChatDB(TestChatBase):
         new_message2 = Message(Question('Question 6'),
                                Answer('Answer 6'),
                                {Tag('tag6')})
-        new_message1.to_file(pathlib.Path(self.db_path.name, '0005.txt'))
-        new_message2.to_file(pathlib.Path(self.db_path.name, '0006.yaml'))
+        new_message1.to_file(pathlib.Path(self.db_path.name, f'0005{msg_suffix}'), mformat='txt')
+        new_message2.to_file(pathlib.Path(self.db_path.name, f'0006{msg_suffix}'), mformat='yaml')
         # read and check them
         chat_db.db_read()
         self.assertEqual(len(chat_db.messages), 6)
-        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, '0005.txt'))
-        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, '0006.yaml'))
+        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, f'0005{msg_suffix}'))
+        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, f'0006{msg_suffix}'))
 
         # create 2 new files in the cache directory
         new_message3 = Message(Question('Question 7'),
-                               Answer('Answer 5'),
+                               Answer('Answer 7'),
                                {Tag('tag7')})
         new_message4 = Message(Question('Question 8'),
-                               Answer('Answer 6'),
+                               Answer('Answer 8'),
                                {Tag('tag8')})
-        new_message3.to_file(pathlib.Path(self.cache_path.name, '0007.txt'))
-        new_message4.to_file(pathlib.Path(self.cache_path.name, '0008.yaml'))
+        new_message3.to_file(pathlib.Path(self.cache_path.name, f'0007{msg_suffix}'), mformat='txt')
+        new_message4.to_file(pathlib.Path(self.cache_path.name, f'0008{msg_suffix}'), mformat='yaml')
         # read and check them
         chat_db.cache_read()
         self.assertEqual(len(chat_db.messages), 8)
         # check that the new message have the cache dir path
-        self.assertEqual(chat_db.messages[6].file_path, pathlib.Path(self.cache_path.name, '0007.txt'))
-        self.assertEqual(chat_db.messages[7].file_path, pathlib.Path(self.cache_path.name, '0008.yaml'))
+        self.assertEqual(chat_db.messages[6].file_path, pathlib.Path(self.cache_path.name, f'0007{msg_suffix}'))
+        self.assertEqual(chat_db.messages[7].file_path, pathlib.Path(self.cache_path.name, f'0008{msg_suffix}'))
         # an the old ones keep their path (since they have not been replaced)
-        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, '0005.txt'))
-        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, '0006.yaml'))
+        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, f'0005{msg_suffix}'))
+        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, f'0006{msg_suffix}'))
 
         # now overwrite two messages in the DB directory
         new_message1.question = Question('New Question 1')
         new_message2.question = Question('New Question 2')
-        new_message1.to_file(pathlib.Path(self.db_path.name, '0005.txt'))
-        new_message2.to_file(pathlib.Path(self.db_path.name, '0006.yaml'))
+        new_message1.to_file(pathlib.Path(self.db_path.name, f'0005{msg_suffix}'), mformat='txt')
+        new_message2.to_file(pathlib.Path(self.db_path.name, f'0006{msg_suffix}'), mformat='yaml')
         # read from the DB dir and check if the modified messages have been updated
         chat_db.db_read()
         self.assertEqual(len(chat_db.messages), 8)
         self.assertEqual(chat_db.messages[4].question, 'New Question 1')
         self.assertEqual(chat_db.messages[5].question, 'New Question 2')
-        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, '0005.txt'))
-        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, '0006.yaml'))
+        self.assertEqual(chat_db.messages[4].file_path, pathlib.Path(self.db_path.name, f'0005{msg_suffix}'))
+        self.assertEqual(chat_db.messages[5].file_path, pathlib.Path(self.db_path.name, f'0006{msg_suffix}'))
 
         # now write the messages from the cache to the DB directory
-        new_message3.to_file(pathlib.Path(self.db_path.name, '0007.txt'))
-        new_message4.to_file(pathlib.Path(self.db_path.name, '0008.yaml'))
+        new_message3.to_file(pathlib.Path(self.db_path.name, f'0007{msg_suffix}'))
+        new_message4.to_file(pathlib.Path(self.db_path.name, f'0008{msg_suffix}'))
         # read and check them
         chat_db.db_read()
         self.assertEqual(len(chat_db.messages), 8)
         # check that they now have the DB path
-        self.assertEqual(chat_db.messages[6].file_path, pathlib.Path(self.db_path.name, '0007.txt'))
-        self.assertEqual(chat_db.messages[7].file_path, pathlib.Path(self.db_path.name, '0008.yaml'))
+        self.assertEqual(chat_db.messages[6].file_path, pathlib.Path(self.db_path.name, f'0007{msg_suffix}'))
+        self.assertEqual(chat_db.messages[7].file_path, pathlib.Path(self.db_path.name, f'0008{msg_suffix}'))
 
     def test_cache_clear(self) -> None:
         # create a new ChatDB instance
         chat_db = ChatDB.from_dir(pathlib.Path(self.cache_path.name),
                                   pathlib.Path(self.db_path.name))
         # check that Message.file_path is correct
-        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, '0001.txt'))
-        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, '0002.yaml'))
-        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, '0003.txt'))
-        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, '0004.yaml'))
+        self.assertEqual(chat_db.messages[0].file_path, pathlib.Path(self.db_path.name, f'0001{msg_suffix}'))
+        self.assertEqual(chat_db.messages[1].file_path, pathlib.Path(self.db_path.name, f'0002{msg_suffix}'))
+        self.assertEqual(chat_db.messages[2].file_path, pathlib.Path(self.db_path.name, f'0003{msg_suffix}'))
+        self.assertEqual(chat_db.messages[3].file_path, pathlib.Path(self.db_path.name, f'0004{msg_suffix}'))
 
         # write the messages to the cache directory
         chat_db.cache_write()
@@ -450,10 +476,10 @@ class TestChatDB(TestChatBase):
         chat_db.db_write()
         db_dir_files = self.message_list(self.db_path)
         self.assertEqual(len(db_dir_files), 4)
-        self.assertIn(pathlib.Path(self.db_path.name, '0001.txt'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0002.yaml'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0003.txt'), db_dir_files)
-        self.assertIn(pathlib.Path(self.db_path.name, '0004.yaml'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0001{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0002{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0003{msg_suffix}'), db_dir_files)
+        self.assertIn(pathlib.Path(self.db_path.name, f'0004{msg_suffix}'), db_dir_files)
 
         # add a new message with empty file_path
         message_empty = Message(question=Question("What the hell am I doing here?"),
@@ -461,7 +487,7 @@ class TestChatDB(TestChatBase):
         # and one for the cache dir
         message_cache = Message(question=Question("What the hell am I doing here?"),
                                 answer=Answer("You're a creep!"),
-                                file_path=pathlib.Path(self.cache_path.name, '0005.txt'))
+                                file_path=pathlib.Path(self.cache_path.name, '0005'))
         chat_db.msg_add([message_empty, message_cache])
 
         # clear the cache and check the cache dir
@@ -523,11 +549,11 @@ class TestChatDB(TestChatBase):
             chat_db.msg_write([message])
 
         # write a message with a valid file_path
-        message.file_path = pathlib.Path(self.cache_path.name) / '123456.txt'
+        message.file_path = pathlib.Path(self.cache_path.name) / '123456'
         chat_db.msg_write([message])
         cache_dir_files = self.message_list(self.cache_path)
         self.assertEqual(len(cache_dir_files), 1)
-        self.assertIn(pathlib.Path(self.cache_path.name, '123456.txt'), cache_dir_files)
+        self.assertIn(pathlib.Path(self.cache_path.name, f'123456{msg_suffix}'), cache_dir_files)
 
     def test_msg_update(self) -> None:
         # create a new ChatDB instance
@@ -563,21 +589,21 @@ class TestChatDB(TestChatBase):
         # search for a DB file in memory
         self.assertEqual(chat_db.msg_find([str(self.message1.file_path)], loc='mem'), [self.message1])
         self.assertEqual(chat_db.msg_find([self.message1.msg_id()], loc='mem'), [self.message1])
-        self.assertEqual(chat_db.msg_find(['0001.txt'], loc='mem'), [self.message1])
+        self.assertEqual(chat_db.msg_find(['0001.msg'], loc='mem'), [self.message1])
         self.assertEqual(chat_db.msg_find(['0001'], loc='mem'), [self.message1])
         # and on disk
         self.assertEqual(chat_db.msg_find([str(self.message2.file_path)], loc='db'), [self.message2])
         self.assertEqual(chat_db.msg_find([self.message2.msg_id()], loc='db'), [self.message2])
-        self.assertEqual(chat_db.msg_find(['0002.yaml'], loc='db'), [self.message2])
+        self.assertEqual(chat_db.msg_find(['0002.msg'], loc='db'), [self.message2])
         self.assertEqual(chat_db.msg_find(['0002'], loc='db'), [self.message2])
         # now search the cache -> expect empty result
         self.assertEqual(chat_db.msg_find([str(self.message3.file_path)], loc='cache'), [])
         self.assertEqual(chat_db.msg_find([self.message3.msg_id()], loc='cache'), [])
-        self.assertEqual(chat_db.msg_find(['0003.txt'], loc='cache'), [])
+        self.assertEqual(chat_db.msg_find(['0003.msg'], loc='cache'), [])
         self.assertEqual(chat_db.msg_find(['0003'], loc='cache'), [])
         # search for multiple messages
         # -> search one twice, expect result to be unique
-        search_names = ['0001', '0002.yaml', self.message3.msg_id(), str(self.message3.file_path)]
+        search_names = ['0001', '0002.msg', self.message3.msg_id(), str(self.message3.file_path)]
         expected_result = [self.message1, self.message2, self.message3]
         result = chat_db.msg_find(search_names, loc='all')
         self.assert_messages_equal(result, expected_result)

tests/test_common.py

@@ -0,0 +1,100 @@
+import unittest
+import argparse
+from typing import Union, Optional
+from chatmastermind.configuration import Config, AIConfig
+from chatmastermind.tags import Tag
+from chatmastermind.message import Message, Answer
+from chatmastermind.chat import Chat
+from chatmastermind.ai import AI, AIResponse, Tokens, AIError
+
+
+class FakeAI(AI):
+    """
+    A mocked version of the 'AI' class.
+    """
+    ID: str
+    name: str
+    config: AIConfig
+
+    def models(self) -> list[str]:
+        raise NotImplementedError
+
+    def tokens(self, data: Union[Message, Chat]) -> int:
+        return 123
+
+    def print(self) -> None:
+        pass
+
+    def print_models(self) -> None:
+        pass
+
+    def __init__(self, ID: str, model: str, error: bool = False):
+        self.ID = ID
+        self.model = model
+        self.error = error
+
+    def request(self,
+                question: Message,
+                chat: Chat,
+                num_answers: int = 1,
+                otags: Optional[set[Tag]] = None) -> AIResponse:
+        """
+        Mock the 'ai.request()' function by either returning fake
+        answers or raising an exception.
+        """
+        if self.error:
+            raise AIError
+        question.answer = Answer("Answer 0")
+        question.tags = set(otags) if otags is not None else None
+        question.ai = self.ID
+        question.model = self.model
+        answers: list[Message] = [question]
+        for n in range(1, num_answers):
+            answers.append(Message(question=question.question,
+                                   answer=Answer(f"Answer {n}"),
+                                   tags=otags,
+                                   ai=self.ID,
+                                   model=self.model))
+        return AIResponse(answers, Tokens(10, 10, 20))
+
+
+class TestWithFakeAI(unittest.TestCase):
+    """
+    Base class for all tests that need to use the FakeAI.
+    """
+    def assert_msgs_equal_except_file_path(self, msg1: list[Message], msg2: list[Message]) -> None:
+        """
+        Compare messages using Question, Answer and all metadata excecot for the file_path.
+        """
+        self.assertEqual(len(msg1), len(msg2))
+        for m1, m2 in zip(msg1, msg2):
+            # exclude the file_path, compare only Q, A and metadata
+            self.assertTrue(m1.equals(m2, file_path=False, verbose=True))
+
+    def assert_msgs_all_equal(self, msg1: list[Message], msg2: list[Message]) -> None:
+        """
+        Compare messages using Question, Answer and ALL metadata.
+        """
+        self.assertEqual(len(msg1), len(msg2))
+        for m1, m2 in zip(msg1, msg2):
+            self.assertTrue(m1.equals(m2, verbose=True))
+
+    def assert_msgs_content_equal(self, msg1: list[Message], msg2: list[Message]) -> None:
+        """
+        Compare messages using only Question and Answer.
+        """
+        self.assertEqual(len(msg1), len(msg2))
+        for m1, m2 in zip(msg1, msg2):
+            self.assertEqual(m1, m2)
+
+    def mock_create_ai(self, args: argparse.Namespace, config: Config) -> AI:
+        """
+        Mocked 'create_ai' that returns a 'FakeAI' instance.
+        """
+        return FakeAI(args.AI, args.model)
+
+    def mock_create_ai_with_error(self, args: argparse.Namespace, config: Config) -> AI:
+        """
+        Mocked 'create_ai' that returns a 'FakeAI' instance.
+        """
+        return FakeAI(args.AI, args.model, error=True)

tests/test_message.py

@@ -1,11 +1,16 @@
 import unittest
 import pathlib
 import tempfile
+import itertools
 from typing import cast
-from chatmastermind.message import source_code, Message, MessageError, Question, Answer, AILine, ModelLine, MessageFilter, message_in
+from chatmastermind.message import source_code, Message, MessageError, Question, Answer, AILine, ModelLine,\
+    MessageFilter, message_in, message_valid_formats
 from chatmastermind.tags import Tag, TagLine
 
 
+msg_suffix: str = Message.file_suffix_write
+
+
 class SourceCodeTestCase(unittest.TestCase):
     def test_source_code_with_include_delims(self) -> None:
         text = """
@@ -101,7 +106,7 @@ class AnswerTestCase(unittest.TestCase):
 
 class MessageToFileTxtTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path = pathlib.Path(self.file.name)
         self.message_complete = Message(Question('This is a question.'),
                                         Answer('This is an answer.'),
@@ -117,7 +122,7 @@ class MessageToFileTxtTestCase(unittest.TestCase):
         self.file_path.unlink()
 
     def test_to_file_txt_complete(self) -> None:
-        self.message_complete.to_file(self.file_path)
+        self.message_complete.to_file(self.file_path, mformat='txt')
 
         with open(self.file_path, "r") as fd:
             content = fd.read()
@@ -132,7 +137,7 @@ This is an answer.
         self.assertEqual(content, expected_content)
 
     def test_to_file_txt_min(self) -> None:
-        self.message_min.to_file(self.file_path)
+        self.message_min.to_file(self.file_path, mformat='txt')
 
         with open(self.file_path, "r") as fd:
             content = fd.read()
@@ -141,11 +146,17 @@ This is a question.
 """
         self.assertEqual(content, expected_content)
 
-    def test_to_file_unsupported_file_type(self) -> None:
+    def test_to_file_unsupported_file_suffix(self) -> None:
         unsupported_file_path = pathlib.Path("example.doc")
         with self.assertRaises(MessageError) as cm:
             self.message_complete.to_file(unsupported_file_path)
-        self.assertEqual(str(cm.exception), "File type '.doc' is not supported")
+        self.assertEqual(str(cm.exception), "File suffix '.doc' is not supported")
+
+    def test_to_file_unsupported_file_format(self) -> None:
+        unsupported_file_format = pathlib.Path(f"example{msg_suffix}")
+        with self.assertRaises(MessageError) as cm:
+            self.message_complete.to_file(unsupported_file_format, mformat='doc')  # type: ignore [arg-type]
+        self.assertEqual(str(cm.exception), "File format 'doc' is not supported")
 
     def test_to_file_no_file_path(self) -> None:
         """
@@ -159,10 +170,24 @@ This is a question.
         # reset the internal file_path
         self.message_complete.file_path = self.file_path
 
+    def test_to_file_txt_auto_suffix(self) -> None:
+        """
+        Test if suffix is auto-generated if omitted.
+        """
+        file_path_no_suffix = self.file_path.with_suffix('')
+        # test with file_path member
+        self.message_min.file_path = file_path_no_suffix
+        self.message_min.to_file(mformat='txt')
+        self.assertEqual(self.message_min.file_path.suffix, msg_suffix)
+        # test with explicit file_path
+        self.message_min.file_path = file_path_no_suffix
+        self.message_min.to_file(file_path=file_path_no_suffix, mformat='txt')
+        self.assertEqual(self.message_min.file_path.suffix, msg_suffix)
+
 
 class MessageToFileYamlTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path = pathlib.Path(self.file.name)
         self.message_complete = Message(Question('This is a question.'),
                                         Answer('This is an answer.'),
@@ -184,7 +209,7 @@ class MessageToFileYamlTestCase(unittest.TestCase):
         self.file_path.unlink()
 
     def test_to_file_yaml_complete(self) -> None:
-        self.message_complete.to_file(self.file_path)
+        self.message_complete.to_file(self.file_path, mformat='yaml')
 
         with open(self.file_path, "r") as fd:
             content = fd.read()
@@ -199,7 +224,7 @@ class MessageToFileYamlTestCase(unittest.TestCase):
         self.assertEqual(content, expected_content)
 
     def test_to_file_yaml_multiline(self) -> None:
-        self.message_multiline.to_file(self.file_path)
+        self.message_multiline.to_file(self.file_path, mformat='yaml')
 
         with open(self.file_path, "r") as fd:
             content = fd.read()
@@ -218,17 +243,31 @@ class MessageToFileYamlTestCase(unittest.TestCase):
         self.assertEqual(content, expected_content)
 
     def test_to_file_yaml_min(self) -> None:
-        self.message_min.to_file(self.file_path)
+        self.message_min.to_file(self.file_path, mformat='yaml')
 
         with open(self.file_path, "r") as fd:
             content = fd.read()
         expected_content = f"{Question.yaml_key}: This is a question.\n"
         self.assertEqual(content, expected_content)
 
+    def test_to_file_yaml_auto_suffix(self) -> None:
+        """
+        Test if suffix is auto-generated if omitted.
+        """
+        file_path_no_suffix = self.file_path.with_suffix('')
+        # test with file_path member
+        self.message_min.file_path = file_path_no_suffix
+        self.message_min.to_file(mformat='yaml')
+        self.assertEqual(self.message_min.file_path.suffix, msg_suffix)
+        # test with explicit file_path
+        self.message_min.file_path = file_path_no_suffix
+        self.message_min.to_file(file_path=file_path_no_suffix, mformat='yaml')
+        self.assertEqual(self.message_min.file_path.suffix, msg_suffix)
+
 
 class MessageFromFileTxtTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path = pathlib.Path(self.file.name)
         with open(self.file_path, "w") as fd:
             fd.write(f"""{TagLine.prefix} tag1 tag2
@@ -239,7 +278,7 @@ This is a question.
 {Answer.txt_header}
 This is an answer.
 """)
-        self.file_min = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_min = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_min = pathlib.Path(self.file_min.name)
         with open(self.file_path_min, "w") as fd:
             fd.write(f"""{Question.txt_header}
@@ -259,7 +298,7 @@ This is a question.
         message = Message.from_file(self.file_path)
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertEqual(message.answer, 'This is an answer.')
         self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
@@ -274,7 +313,7 @@ This is a question.
         message = Message.from_file(self.file_path_min)
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertEqual(message.file_path, self.file_path_min)
         self.assertIsNone(message.answer)
@@ -284,7 +323,7 @@ This is a question.
                                     MessageFilter(tags_or={Tag('tag1')}))
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertEqual(message.answer, 'This is an answer.')
         self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
@@ -311,13 +350,13 @@ This is a question.
                                     MessageFilter(tags_not={Tag('tag1')}))
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertSetEqual(cast(set[Tag], message.tags), set())
         self.assertEqual(message.file_path, self.file_path_min)
 
     def test_from_file_not_exists(self) -> None:
-        file_not_exists = pathlib.Path("example.txt")
+        file_not_exists = pathlib.Path(f"example{msg_suffix}")
         with self.assertRaises(MessageError) as cm:
             Message.from_file(file_not_exists)
         self.assertEqual(str(cm.exception), f"Message file '{file_not_exists}' does not exist")
@@ -396,7 +435,7 @@ This is a question.
 
 class MessageFromFileYamlTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path = pathlib.Path(self.file.name)
         with open(self.file_path, "w") as fd:
             fd.write(f"""
@@ -410,7 +449,7 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
   - tag1
   - tag2
 """)
-        self.file_min = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_min = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_min = pathlib.Path(self.file_min.name)
         with open(self.file_path_min, "w") as fd:
             fd.write(f"""
@@ -431,7 +470,7 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
         message = Message.from_file(self.file_path)
         self.assertIsInstance(message, Message)
         self.assertIsNotNone(message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertEqual(message.answer, 'This is an answer.')
         self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
@@ -446,14 +485,14 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
         message = Message.from_file(self.file_path_min)
         self.assertIsInstance(message, Message)
         self.assertIsNotNone(message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertSetEqual(cast(set[Tag], message.tags), set())
         self.assertEqual(message.file_path, self.file_path_min)
         self.assertIsNone(message.answer)
 
     def test_from_file_not_exists(self) -> None:
-        file_not_exists = pathlib.Path("example.yaml")
+        file_not_exists = pathlib.Path(f"example{msg_suffix}")
         with self.assertRaises(MessageError) as cm:
             Message.from_file(file_not_exists)
         self.assertEqual(str(cm.exception), f"Message file '{file_not_exists}' does not exist")
@@ -463,7 +502,7 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
                                     MessageFilter(tags_or={Tag('tag1')}))
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertEqual(message.answer, 'This is an answer.')
         self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
@@ -484,7 +523,7 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
                                     MessageFilter(tags_not={Tag('tag1')}))
         self.assertIsNotNone(message)
         self.assertIsInstance(message, Message)
-        if message:  # mypy bug
+        assert message
         self.assertEqual(message.question, 'This is a question.')
         self.assertSetEqual(cast(set[Tag], message.tags), set())
         self.assertEqual(message.file_path, self.file_path_min)
@@ -563,7 +602,7 @@ class MessageFromFileYamlTestCase(unittest.TestCase):
 
 class TagsFromFileTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file_txt = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_txt = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_txt = pathlib.Path(self.file_txt.name)
         with open(self.file_path_txt, "w") as fd:
             fd.write(f"""{TagLine.prefix} tag1 tag2 ptag3
@@ -572,7 +611,7 @@ This is a question.
 {Answer.txt_header}
 This is an answer.
 """)
-        self.file_txt_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_txt_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_txt_no_tags = pathlib.Path(self.file_txt_no_tags.name)
         with open(self.file_path_txt_no_tags, "w") as fd:
             fd.write(f"""{Question.txt_header}
@@ -580,7 +619,7 @@ This is a question.
 {Answer.txt_header}
 This is an answer.
 """)
-        self.file_txt_tags_empty = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_txt_tags_empty = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_txt_tags_empty = pathlib.Path(self.file_txt_tags_empty.name)
         with open(self.file_path_txt_tags_empty, "w") as fd:
             fd.write(f"""TAGS:
@@ -589,7 +628,7 @@ This is a question.
 {Answer.txt_header}
 This is an answer.
 """)
-        self.file_yaml = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_yaml = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_yaml = pathlib.Path(self.file_yaml.name)
         with open(self.file_path_yaml, "w") as fd:
             fd.write(f"""
@@ -602,7 +641,7 @@ This is an answer.
   - tag2
   - ptag3
 """)
-        self.file_yaml_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_yaml_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path_yaml_no_tags = pathlib.Path(self.file_yaml_no_tags.name)
         with open(self.file_path_yaml_no_tags, "w") as fd:
             fd.write(f"""
@@ -679,24 +718,25 @@ class TagsFromDirTestCase(unittest.TestCase):
             {Tag('ctag5'), Tag('ctag6')}
         ]
         self.files = [
-            pathlib.Path(self.temp_dir.name, 'file1.txt'),
-            pathlib.Path(self.temp_dir.name, 'file2.yaml'),
-            pathlib.Path(self.temp_dir.name, 'file3.txt')
+            pathlib.Path(self.temp_dir.name, f'file1{msg_suffix}'),
+            pathlib.Path(self.temp_dir.name, f'file2{msg_suffix}'),
+            pathlib.Path(self.temp_dir.name, f'file3{msg_suffix}')
         ]
         self.files_no_tags = [
-            pathlib.Path(self.temp_dir_no_tags.name, 'file4.txt'),
-            pathlib.Path(self.temp_dir_no_tags.name, 'file5.yaml'),
-            pathlib.Path(self.temp_dir_no_tags.name, 'file6.txt')
+            pathlib.Path(self.temp_dir_no_tags.name, f'file4{msg_suffix}'),
+            pathlib.Path(self.temp_dir_no_tags.name, f'file5{msg_suffix}'),
+            pathlib.Path(self.temp_dir_no_tags.name, f'file6{msg_suffix}')
         ]
+        mformats = itertools.cycle(message_valid_formats)
         for file, tags in zip(self.files, self.tag_sets):
             message = Message(Question('This is a question.'),
                               Answer('This is an answer.'),
                               tags)
-            message.to_file(file)
+            message.to_file(file, next(mformats))
         for file in self.files_no_tags:
             message = Message(Question('This is a question.'),
                               Answer('This is an answer.'))
-            message.to_file(file)
+            message.to_file(file, next(mformats))
 
     def tearDown(self) -> None:
         self.temp_dir.cleanup()
@@ -719,7 +759,7 @@ class TagsFromDirTestCase(unittest.TestCase):
 
 class MessageIDTestCase(unittest.TestCase):
     def setUp(self) -> None:
-        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix=msg_suffix)
         self.file_path = pathlib.Path(self.file.name)
         self.message = Message(Question('This is a question.'),
                                file_path=self.file_path)

tests/test_question_cmd.py

@@ -1,31 +1,23 @@
 import os
-import unittest
 import argparse
 import tempfile
+from copy import copy
 from pathlib import Path
 from unittest import mock
-from unittest.mock import MagicMock, call, ANY
-from typing import Optional
+from unittest.mock import MagicMock, call
 from chatmastermind.configuration import Config
 from chatmastermind.commands.question import create_message, question_cmd
 from chatmastermind.tags import Tag
 from chatmastermind.message import Message, Question, Answer
 from chatmastermind.chat import Chat, ChatDB
-from chatmastermind.ai import AI, AIResponse, Tokens, AIError
+from chatmastermind.ai import AIError
+from .test_common import TestWithFakeAI
 
 
-class TestQuestionCmdBase(unittest.TestCase):
-    def assert_messages_equal(self, msg1: list[Message], msg2: list[Message]) -> None:
-        """
-        Compare messages using more than just Question and Answer.
-        """
-        self.assertEqual(len(msg1), len(msg2))
-        for m1, m2 in zip(msg1, msg2):
-            # exclude the file_path, compare only Q, A and metadata
-            self.assertTrue(m1.equals(m2, file_path=False, verbose=True))
+msg_suffix = Message.file_suffix_write
 
 
-class TestMessageCreate(TestQuestionCmdBase):
+class TestMessageCreate(TestWithFakeAI):
     """
     Test if messages created by the 'question' command have
     the correct format.
@@ -94,7 +86,7 @@ Aaaand again some text."""
 
     def message_list(self, tmp_dir: tempfile.TemporaryDirectory) -> list[Path]:
         # exclude '.next'
-        return list(Path(tmp_dir.name).glob('*.[ty]*'))
+        return list(Path(tmp_dir.name).glob(f'*{msg_suffix}'))
 
     def test_message_file_created(self) -> None:
         self.args.ask = ["What is this?"]
@@ -212,7 +204,7 @@ It is embedded code
 """))
 
 
-class TestQuestionCmd(TestQuestionCmdBase):
+class TestQuestionCmd(TestWithFakeAI):
 
     def setUp(self) -> None:
         # create DB and cache
@@ -227,8 +219,8 @@ class TestQuestionCmd(TestQuestionCmdBase):
             ask=['What is the meaning of life?'],
             num_answers=1,
             output_tags=['science'],
-            AI='openai',
-            model='gpt-3.5-turbo',
+            AI='FakeAI',
+            model='FakeModel',
             or_tags=None,
             and_tags=None,
             exclude_tags=None,
@@ -239,57 +231,27 @@ class TestQuestionCmd(TestQuestionCmdBase):
             process=None,
             overwrite=None
         )
-        # create a mock AI instance
-        self.ai = MagicMock(spec=AI)
-        self.ai.request.side_effect = self.mock_request
-
-    def input_message(self, args: argparse.Namespace) -> Message:
-        """
-        Create the expected input message for a question using the
-        given arguments.
-        """
-        # NOTE: we only use the first question from the "ask" list
-        # -> message creation using "question.create_message()" is
-        #    tested above
-        # the answer is always empty for the input message
-        return Message(Question(args.ask[0]),
-                       tags=args.output_tags,
-                       ai=args.AI,
-                       model=args.model)
-
-    def mock_request(self,
-                     question: Message,
-                     chat: Chat,
-                     num_answers: int = 1,
-                     otags: Optional[set[Tag]] = None) -> AIResponse:
-        """
-        Mock the 'ai.request()' function
-        """
-        question.answer = Answer("Answer 0")
-        question.tags = set(otags) if otags else None
-        question.ai = 'FakeAI'
-        question.model = 'FakeModel'
-        answers: list[Message] = [question]
-        for n in range(1, num_answers):
-            answers.append(Message(question=question.question,
-                                   answer=Answer(f"Answer {n}"),
-                                   tags=otags,
-                                   ai='FakeAI',
-                                   model='FakeModel'))
-        return AIResponse(answers, Tokens(10, 10, 20))
 
     def message_list(self, tmp_dir: tempfile.TemporaryDirectory) -> list[Path]:
         # exclude '.next'
-        return sorted([f for f in Path(tmp_dir.name).glob('*.[ty]*')])
+        return sorted([f for f in Path(tmp_dir.name).glob(f'*{msg_suffix}')])
+
+
+class TestQuestionCmdAsk(TestQuestionCmd):
 
     @mock.patch('chatmastermind.commands.question.create_ai')
     def test_ask_single_answer(self, mock_create_ai: MagicMock) -> None:
         """
         Test single answer with no errors.
         """
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        expected_responses = self.mock_request(expected_question,
+        mock_create_ai.side_effect = self.mock_create_ai
+        expected_question = Message(Question(self.args.ask[0]),
+                                    tags=set(self.args.output_tags),
+                                    ai=self.args.AI,
+                                    model=self.args.model,
+                                    file_path=Path('<NOT COMPARED>'))
+        fake_ai = self.mock_create_ai(self.args, self.config)
+        expected_responses = fake_ai.request(expected_question,
                                              Chat([]),
                                              self.args.num_answers,
                                              self.args.output_tags).messages
@@ -297,17 +259,12 @@ class TestQuestionCmd(TestQuestionCmdBase):
         # execute the command
         question_cmd(self.args, self.config)
 
-        # check for correct request call
-        self.ai.request.assert_called_once_with(expected_question,
-                                                ANY,
-                                                self.args.num_answers,
-                                                self.args.output_tags)
         # check for the expected message files
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
         cached_msg = chat.msg_gather(loc='cache')
         self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        self.assert_msgs_equal_except_file_path(cached_msg, expected_responses)
 
     @mock.patch('chatmastermind.commands.question.ChatDB.from_dir')
     @mock.patch('chatmastermind.commands.question.create_ai')
@@ -318,9 +275,14 @@ class TestQuestionCmd(TestQuestionCmdBase):
         chat = MagicMock(spec=ChatDB)
         mock_from_dir.return_value = chat
 
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        expected_responses = self.mock_request(expected_question,
+        mock_create_ai.side_effect = self.mock_create_ai
+        expected_question = Message(Question(self.args.ask[0]),
+                                    tags=set(self.args.output_tags),
+                                    ai=self.args.AI,
+                                    model=self.args.model,
+                                    file_path=Path('<NOT COMPARED>'))
+        fake_ai = self.mock_create_ai(self.args, self.config)
+        expected_responses = fake_ai.request(expected_question,
                                              Chat([]),
                                              self.args.num_answers,
                                              self.args.output_tags).messages
@@ -328,12 +290,6 @@ class TestQuestionCmd(TestQuestionCmdBase):
         # execute the command
         question_cmd(self.args, self.config)
 
-        # check for correct request call
-        self.ai.request.assert_called_once_with(expected_question,
-                                                chat,
-                                                self.args.num_answers,
-                                                self.args.output_tags)
-
         # check for the correct ChatDB calls:
         # - initial question has been written (prior to the actual request)
         # - responses have been written (after the request)
@@ -350,86 +306,98 @@ class TestQuestionCmd(TestQuestionCmdBase):
         Provoke an error during the AI request and verify that the question
         has been correctly stored in the cache.
         """
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        self.ai.request.side_effect = AIError
+        mock_create_ai.side_effect = self.mock_create_ai_with_error
+        expected_question = Message(Question(self.args.ask[0]),
+                                    tags=set(self.args.output_tags),
+                                    ai=self.args.AI,
+                                    model=self.args.model,
+                                    file_path=Path('<NOT COMPARED>'))
 
         # execute the command
         with self.assertRaises(AIError):
             question_cmd(self.args, self.config)
 
-        # check for correct request call
-        self.ai.request.assert_called_once_with(expected_question,
-                                                ANY,
-                                                self.args.num_answers,
-                                                self.args.output_tags)
         # check for the expected message files
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
         cached_msg = chat.msg_gather(loc='cache')
         self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, [expected_question])
+        self.assert_msgs_equal_except_file_path(cached_msg, [expected_question])
+
+
+class TestQuestionCmdRepeat(TestQuestionCmd):
 
     @mock.patch('chatmastermind.commands.question.create_ai')
     def test_repeat_single_question(self, mock_create_ai: MagicMock) -> None:
         """
         Repeat a single question.
         """
-        # 1. ask a question
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        expected_responses = self.mock_request(expected_question,
-                                               Chat([]),
-                                               self.args.num_answers,
-                                               self.args.output_tags).messages
-        question_cmd(self.args, self.config)
+        mock_create_ai.side_effect = self.mock_create_ai
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
-        cached_msg = chat.msg_gather(loc='cache')
-        self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        # create a message
+        message = Message(Question(self.args.ask[0]),
+                          Answer('Old Answer'),
+                          tags=set(self.args.output_tags),
+                          ai=self.args.AI,
+                          model=self.args.model,
+                          file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        chat.msg_write([message])
 
-        # 2. repeat the last question (without overwriting)
+        # repeat the last question (without overwriting)
         # -> expect two identical messages (except for the file_path)
         self.args.ask = None
         self.args.repeat = []
         self.args.overwrite = False
-        expected_responses += expected_responses
+        expected_response = Message(Question(message.question),
+                                    Answer('Answer 0'),
+                                    ai=message.ai,
+                                    model=message.model,
+                                    tags=message.tags,
+                                    file_path=Path('<NOT COMPARED>'))
+        # we expect the original message + the one with the new response
+        expected_responses = [message] + [expected_response]
         question_cmd(self.args, self.config)
         cached_msg = chat.msg_gather(loc='cache')
+        print(self.message_list(self.cache_dir))
         self.assertEqual(len(self.message_list(self.cache_dir)), 2)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        self.assert_msgs_equal_except_file_path(cached_msg, expected_responses)
 
     @mock.patch('chatmastermind.commands.question.create_ai')
     def test_repeat_single_question_overwrite(self, mock_create_ai: MagicMock) -> None:
         """
         Repeat a single question and overwrite the old one.
         """
-        # 1. ask a question
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        expected_responses = self.mock_request(expected_question,
-                                               Chat([]),
-                                               self.args.num_answers,
-                                               self.args.output_tags).messages
-        question_cmd(self.args, self.config)
+        mock_create_ai.side_effect = self.mock_create_ai
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
+        # create a message
+        message = Message(Question(self.args.ask[0]),
+                          Answer('Old Answer'),
+                          tags=set(self.args.output_tags),
+                          ai=self.args.AI,
+                          model=self.args.model,
+                          file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        chat.msg_write([message])
         cached_msg = chat.msg_gather(loc='cache')
         assert cached_msg[0].file_path
         cached_msg_file_id = cached_msg[0].file_path.stem
-        self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
 
-        # 2. repeat the last question (WITH overwriting)
-        # -> expect a single message afterwards
+        # repeat the last question (WITH overwriting)
+        # -> expect a single message afterwards (with a new answer)
         self.args.ask = None
         self.args.repeat = []
         self.args.overwrite = True
+        expected_response = Message(Question(message.question),
+                                    Answer('Answer 0'),
+                                    ai=message.ai,
+                                    model=message.model,
+                                    tags=message.tags,
+                                    file_path=Path('<NOT COMPARED>'))
         question_cmd(self.args, self.config)
         cached_msg = chat.msg_gather(loc='cache')
         self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        self.assert_msgs_equal_except_file_path(cached_msg, [expected_response])
         # also check that the file ID has not been changed
         assert cached_msg[0].file_path
         self.assertEqual(cached_msg_file_id, cached_msg[0].file_path.stem)
@@ -439,35 +407,37 @@ class TestQuestionCmd(TestQuestionCmdBase):
         """
         Repeat a single question after an error.
         """
-        # 1. ask a question and provoke an error
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        self.ai.request.side_effect = AIError
-        with self.assertRaises(AIError):
-            question_cmd(self.args, self.config)
+        mock_create_ai.side_effect = self.mock_create_ai
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
+        # create a question WITHOUT an answer
+        # -> just like after an error, which is tested above
+        message = Message(Question(self.args.ask[0]),
+                          tags=set(self.args.output_tags),
+                          ai=self.args.AI,
+                          model=self.args.model,
+                          file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        chat.msg_write([message])
         cached_msg = chat.msg_gather(loc='cache')
         assert cached_msg[0].file_path
         cached_msg_file_id = cached_msg[0].file_path.stem
-        self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, [expected_question])
 
-        # 2. repeat the last question (without overwriting)
+        # repeat the last question (without overwriting)
         # -> expect a single message because if the original has
         #    no answer, it should be overwritten by default
         self.args.ask = None
         self.args.repeat = []
         self.args.overwrite = False
-        self.ai.request.side_effect = self.mock_request
-        expected_responses = self.mock_request(expected_question,
-                                               Chat([]),
-                                               self.args.num_answers,
-                                               self.args.output_tags).messages
+        expected_response = Message(Question(message.question),
+                                    Answer('Answer 0'),
+                                    ai=message.ai,
+                                    model=message.model,
+                                    tags=message.tags,
+                                    file_path=Path('<NOT COMPARED>'))
         question_cmd(self.args, self.config)
         cached_msg = chat.msg_gather(loc='cache')
         self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        self.assert_msgs_equal_except_file_path(cached_msg, [expected_response])
         # also check that the file ID has not been changed
         assert cached_msg[0].file_path
         self.assertEqual(cached_msg_file_id, cached_msg[0].file_path.stem)
@@ -477,37 +447,130 @@ class TestQuestionCmd(TestQuestionCmdBase):
         """
         Repeat a single question with new arguments.
         """
-        # 1. ask a question
-        mock_create_ai.return_value = self.ai
-        expected_question = self.input_message(self.args)
-        expected_responses = self.mock_request(expected_question,
-                                               Chat([]),
-                                               self.args.num_answers,
-                                               self.args.output_tags).messages
-        question_cmd(self.args, self.config)
+        mock_create_ai.side_effect = self.mock_create_ai
         chat = ChatDB.from_dir(Path(self.cache_dir.name),
                                Path(self.db_dir.name))
+        # create a message
+        message = Message(Question(self.args.ask[0]),
+                          Answer('Old Answer'),
+                          tags=set(self.args.output_tags),
+                          ai=self.args.AI,
+                          model=self.args.model,
+                          file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        chat.msg_write([message])
         cached_msg = chat.msg_gather(loc='cache')
-        self.assertEqual(len(self.message_list(self.cache_dir)), 1)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        assert cached_msg[0].file_path
 
-        # 2. repeat the last question with new arguments (without overwriting)
-        # -> expect two messages with identical question and answer, but different metadata
+        # repeat the last question with new arguments (without overwriting)
+        # -> expect two messages with identical question but different metadata and new answer
         self.args.ask = None
         self.args.repeat = []
         self.args.overwrite = False
         self.args.output_tags = ['newtag']
         self.args.AI = 'newai'
         self.args.model = 'newmodel'
-        new_expected_question = Message(question=Question(expected_question.question),
-                                        tags=set(self.args.output_tags),
-                                        ai=self.args.AI,
-                                        model=self.args.model)
-        expected_responses += self.mock_request(new_expected_question,
-                                                Chat([]),
-                                                self.args.num_answers,
-                                                set(self.args.output_tags)).messages
+        new_expected_response = Message(Question(message.question),
+                                        Answer('Answer 0'),
+                                        ai='newai',
+                                        model='newmodel',
+                                        tags={Tag('newtag')},
+                                        file_path=Path('<NOT COMPARED>'))
         question_cmd(self.args, self.config)
         cached_msg = chat.msg_gather(loc='cache')
         self.assertEqual(len(self.message_list(self.cache_dir)), 2)
-        self.assert_messages_equal(cached_msg, expected_responses)
+        self.assert_msgs_equal_except_file_path(cached_msg, [message] + [new_expected_response])
+
+    @mock.patch('chatmastermind.commands.question.create_ai')
+    def test_repeat_single_question_new_args_overwrite(self, mock_create_ai: MagicMock) -> None:
+        """
+        Repeat a single question with new arguments, overwriting the old one.
+        """
+        mock_create_ai.side_effect = self.mock_create_ai
+        chat = ChatDB.from_dir(Path(self.cache_dir.name),
+                               Path(self.db_dir.name))
+        # create a message
+        message = Message(Question(self.args.ask[0]),
+                          Answer('Old Answer'),
+                          tags=set(self.args.output_tags),
+                          ai=self.args.AI,
+                          model=self.args.model,
+                          file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        chat.msg_write([message])
+        cached_msg = chat.msg_gather(loc='cache')
+        assert cached_msg[0].file_path
+
+        # repeat the last question with new arguments
+        self.args.ask = None
+        self.args.repeat = []
+        self.args.overwrite = True
+        self.args.output_tags = ['newtag']
+        self.args.AI = 'newai'
+        self.args.model = 'newmodel'
+        new_expected_response = Message(Question(message.question),
+                                        Answer('Answer 0'),
+                                        ai='newai',
+                                        model='newmodel',
+                                        tags={Tag('newtag')},
+                                        file_path=Path('<NOT COMPARED>'))
+        question_cmd(self.args, self.config)
+        cached_msg = chat.msg_gather(loc='cache')
+        self.assertEqual(len(self.message_list(self.cache_dir)), 1)
+        self.assert_msgs_equal_except_file_path(cached_msg, [new_expected_response])
+
+    @mock.patch('chatmastermind.commands.question.create_ai')
+    def test_repeat_multiple_questions(self, mock_create_ai: MagicMock) -> None:
+        """
+        Repeat multiple  questions.
+        """
+        mock_create_ai.side_effect = self.mock_create_ai
+        chat = ChatDB.from_dir(Path(self.cache_dir.name),
+                               Path(self.db_dir.name))
+        # 1. === create three questions ===
+        # cached message without an answer
+        message1 = Message(Question(self.args.ask[0]),
+                           tags=self.args.output_tags,
+                           ai=self.args.AI,
+                           model=self.args.model,
+                           file_path=Path(self.cache_dir.name) / f'0001{msg_suffix}')
+        # cached message with an answer
+        message2 = Message(Question(self.args.ask[0]),
+                           Answer('Old Answer'),
+                           tags=self.args.output_tags,
+                           ai=self.args.AI,
+                           model=self.args.model,
+                           file_path=Path(self.cache_dir.name) / f'0002{msg_suffix}')
+        # DB message without an answer
+        message3 = Message(Question(self.args.ask[0]),
+                           tags=self.args.output_tags,
+                           ai=self.args.AI,
+                           model=self.args.model,
+                           file_path=Path(self.db_dir.name) / f'0003{msg_suffix}')
+        chat.msg_write([message1, message2, message3])
+        questions = [message1, message2, message3]
+        expected_responses: list[Message] = []
+        fake_ai = self.mock_create_ai(self.args, self.config)
+        for question in questions:
+            # since the  message's answer is modified, we use a copy
+            # -> the original is used for comparison below
+            expected_responses += fake_ai.request(copy(question),
+                                                  Chat([]),
+                                                  self.args.num_answers,
+                                                  set(self.args.output_tags)).messages
+
+        # 2. === repeat all three questions (without overwriting) ===
+        self.args.ask = None
+        self.args.repeat = ['0001', '0002', '0003']
+        self.args.overwrite = False
+        question_cmd(self.args, self.config)
+        # two new files should be in the cache directory
+        # * the repeated cached message with answer
+        # * the repeated DB message
+        # -> the cached message without answer should be overwritten
+        self.assertEqual(len(self.message_list(self.cache_dir)), 4)
+        self.assertEqual(len(self.message_list(self.db_dir)), 1)
+        expected_cache_messages = [expected_responses[0], message2, expected_responses[1], expected_responses[2]]
+        cached_msg = chat.msg_gather(loc='cache')
+        self.assert_msgs_equal_except_file_path(cached_msg, expected_cache_messages)
+        # check that the DB message has not been modified at all
+        db_msg = chat.msg_gather(loc='db')
+        self.assert_msgs_all_equal(db_msg, [message3])