Add pytest unit testing framework

mautrix_telegram/commands/handler.py

@@ -14,17 +14,29 @@
 #
 # You should have received a copy of the GNU Affero General Public License
 # along with this program.  If not, see <https://www.gnu.org/licenses/>.
-from typing import Awaitable, Callable, Dict, List, NamedTuple, Optional
-import traceback
+"""This module contains classes handling commands issued by Matrix users."""
+from typing import (
+    Any,
+    Awaitable,
+    Callable,
+    Coroutine,
+    Dict,
+    List,
+    NamedTuple,
+    Optional,
+    Union,
+    NewType,
+)
 import logging
+import traceback
 
 import commonmark
 
 from telethon.errors import FloodWaitError
 
-from ..types import MatrixRoomID, MatrixEventID
-from ..util import format_duration
-from .. import user as u, context as c
+from mautrix_telegram.types import MatrixRoomID, MatrixEventID
+from mautrix_telegram.util import format_duration
+from mautrix_telegram import user as u, context as c
 
 command_handlers = {}  # type: Dict[str, CommandHandler]
 
@@ -59,7 +71,28 @@ md_parser = commonmark.Parser()
 md_renderer = HtmlEscapingRenderer()
 
 
+def ensure_trailing_newline(s: str) -> str:
+    """Returns the passed string, but with a guaranteed trailing newline."""
+    return s + ("" if s[-1] == "\n" else "\n")
+
+
 class CommandEvent:
+    """Holds information about a command issued in a Matrix room.
+
+    When a Matrix command was issued to the bot, CommandEvent will hold
+    information regarding the event.
+
+    Attributes:
+        room_id: The id of the Matrix room in which the command was issued.
+        event_id: The id of the matrix event which contained the command.
+        sender: The user who issued the command.
+        command: The issued command.
+        args: Arguments given with the issued command.
+        is_management: Determines whether the room in which the command wa
+            issued is a management room.
+        is_portal: Determines whether the room in which the command was issued
+            is a portal.
+    """
     def __init__(self, processor: 'CommandProcessor', room: MatrixRoomID, event: MatrixEventID,
                  sender: u.User, command: str, args: List[str], is_management: bool,
                  is_portal: bool) -> None:
@@ -78,28 +111,109 @@ class CommandEvent:
         self.is_management = is_management
         self.is_portal = is_portal
 
-    def reply(self, message: str, allow_html: bool = False, render_markdown: bool = True
-              ) -> Awaitable[Dict]:
-        message = message.replace("$cmdprefix+sp ",
-                                  "" if self.is_management else f"{self.command_prefix} ")
-        message = message.replace("$cmdprefix", self.command_prefix)
-        html = None
+    def reply(
+            self,
+            message: str,
+            allow_html: bool = False,
+            render_markdown: bool = True,
+        ) -> Awaitable[Dict]:
+        """Write a reply to the room in which the command was issued.
+
+        Replaces occurences of "$cmdprefix" in the message with the command
+        prefix and replaces occurences of "$cmdprefix+sp " with the command
+        prefix if the command was not issued in a management room.
+        If allow_html and render_markdown are both False, the message will not
+        be rendered to html and sending of html is disabled.
+
+        Args:
+            message: The message to post in the room.
+            allow_html: Escape html in the message or don't render html at all
+                if markdown is disabled.
+            render_markdown: Use markdown formatting to render the passed
+                message to html.
+
+        Returns:
+            Handler for the message sending function.
+        """
+        message_cmd = self._replace_command_prefix(message)
+        html = self._render_message(
+            message_cmd, allow_html=allow_html, render_markdown=render_markdown
+        )
+
+        return self.az.intent.send_notice(self.room_id, message_cmd, html=html)
+
+    def mark_read(self) -> Awaitable[Dict]:
+        """Marks the command as read by the bot."""
+        return self.az.intent.mark_read(self.room_id, self.event_id)
+
+    def _replace_command_prefix(self, message: str) -> str:
+        """Returns the string with the proper command prefix entered."""
+        message = message.replace(
+            "$cmdprefix+sp ", "" if self.is_management else f"{self.command_prefix} "
+        )
+        return message.replace("$cmdprefix", self.command_prefix)
+
+    def _render_message(
+        self, message: str, allow_html: bool, render_markdown: bool
+    ) -> Optional[str]:
+        """Renders the message as HTML.
+
+        Args:
+            allow_html: Flag to allow custom HTML in the message.
+            render_markdown: If true, markdown styling is applied to the message.
+
+        Returns:
+            The message rendered as HTML.
+            None is returned if no styled output is required.
+        """
+        html = ""
         if render_markdown:
             md_renderer.allow_html = allow_html
             html = md_renderer.render(md_parser.parse(message))
         elif allow_html:
             html = message
-        return self.az.intent.send_notice(self.room_id, message, html=html)
-
-    def mark_read(self) -> Awaitable[Dict]:
-        return self.az.intent.mark_read(self.room_id, self.event_id)
+        return ensure_trailing_newline(html) if html else None
 
 
 class CommandHandler:
+    """A command which can be executed from a Matrix room.
+
+    The command manages its permission and help texts.
+    When called, it will check the permission of the command event and execute
+    the command or, in case of error, report back to the user.
+
+    Attributes:
+        needs_auth: Flag indicating if the sender is required to be logged in.
+        needs_puppeting: Flag indicating if the sender is required to use
+            Telegram puppeteering for this command.
+        needs_matrix_puppeting: Flag indicating if the sender is required to use
+            Matrix pupeteering.
+        needs_admin: Flag for whether only admin users can issue this command.
+        management_only: Whether the command can exclusively be issued in a
+            management room.
+        name: The name of this command.
+        help_section: Section of the help in which this command will appear.
+    """
     def __init__(self, handler: Callable[[CommandEvent], Awaitable[Dict]], needs_auth: bool,
                  needs_puppeting: bool, needs_matrix_puppeting: bool, needs_admin: bool,
                  management_only: bool, name: str, help_text: str, help_args: str,
                  help_section: HelpSection) -> None:
+        """
+        Args:
+            handler: The function handling the execution of this command.
+            needs_auth: Flag indicating if the sender is required to be logged in.
+            needs_puppeting: Flag indicating if the sender is required to use
+                Telegram puppeteering for this command.
+            needs_matrix_puppeting: Flag indicating if the sender is required to
+                use Matrix pupeteering.
+            needs_admin: Flag for whether only admin users can issue this command.
+            management_only: Whether the command can exclusively be issued
+                in a management room.
+            name: The name of this command.
+            help_text: The text displayed in the help for this command.
+            help_args: Help text for the arguments of this command.
+            help_section: Section of the help in which this command will appear.
+        """
         self._handler = handler
         self.needs_auth = needs_auth
         self.needs_puppeting = needs_puppeting
@@ -112,6 +226,14 @@ class CommandHandler:
         self.help_section = help_section
 
     async def get_permission_error(self, evt: CommandEvent) -> Optional[str]:
+        """Returns the reason why the command could not be issued.
+
+        Args:
+            evt: The event for which to get the error information.
+
+        Returns:
+            A string describing the error or None if there was no error.
+        """
         if self.management_only and not evt.is_management:
             return (f"`{evt.command}` is a restricted command: "
                     "you may only run it in management rooms.")
@@ -127,6 +249,22 @@ class CommandHandler:
 
     def has_permission(self, is_management: bool, puppet_whitelisted: bool,
                        matrix_puppet_whitelisted: bool, is_admin: bool, is_logged_in: bool) -> bool:
+        """Checks the permission for this command with the given status.
+
+        Args:
+            is_management: If the room in which the command will be issued is a
+                management room.
+            puppet_whitelited: If the connected Telegram account puppet is
+                allowed to issue the command.
+            matrix_puppet_whitelisted: If the connected Matrix account puppet is
+                allowed to issue the command.
+            is_admin: If the issuing user is an admin.
+            is_logged_in: If the issuing user is logged in.
+
+        Returns:
+            True if a user with the given state is allowed to issue the
+            command.
+        """
         return ((not self.management_only or is_management) and
                 (not self.needs_puppeting or puppet_whitelisted) and
                 (not self.needs_matrix_puppeting or matrix_puppet_whitelisted) and
@@ -134,6 +272,17 @@ class CommandHandler:
                 (not self.needs_auth or is_logged_in))
 
     async def __call__(self, evt: CommandEvent) -> Dict:
+        """Executes the command if evt was issued with proper rights.
+
+        Args:
+            evt: The CommandEvent for which to check permissions.
+
+        Returns:
+            The result of the command or the error message function.
+
+        Raises:
+            FloodWaitError
+        """
         error = await self.get_permission_error(evt)
         if error is not None:
             return await evt.reply(error)
@@ -141,10 +290,12 @@ class CommandHandler:
 
     @property
     def has_help(self) -> bool:
+        """Returns true if this command has a help text."""
         return bool(self.help_section) and bool(self._help_text)
 
     @property
     def help(self) -> str:
+        """Returns the help text to this command."""
         return f"**{self.name}** {self._help_args} - {self._help_text}"
 
 
@@ -173,6 +324,7 @@ def command_handler(_func: Optional[Callable[[CommandEvent], Awaitable[Dict]]] =
 
 
 class CommandProcessor:
+    """Handles the raw commands issued by a user to the Matrix bot."""
     log = logging.getLogger("mau.commands")
 
     def __init__(self, context: c.Context) -> None:
@@ -183,6 +335,28 @@ class CommandProcessor:
     async def handle(self, room: MatrixRoomID, event_id: MatrixEventID, sender: u.User,
                      command: str, args: List[str], is_management: bool, is_portal: bool
                      ) -> Optional[Dict]:
+        """Handles the raw commands issued by a user to the Matrix bot.
+
+        If the command is not known, it might be a followup command and is
+        delegated to a command handler registered for that purpose in the
+        senders command_status as "next".
+
+        Args:
+            room: ID of the Matrix room in which the command was issued.
+            event_id: ID of the event by which the command was issued.
+            sender: The sender who issued the command.
+            command: The issued command, case insensitive.
+            args: Arguments given with the command.
+            is_management: Whether the room is a management room.
+            is_portal: Whether the room is a portal.
+
+        Returns:
+            The result of the error message function or None if no error
+            occured. Unknown and delegated commands do not count as errors.
+        """
+        if not command_handlers or "unknown-command" not in command_handlers:
+            raise ValueError("command_handlers are not properly initialized.")
+
         evt = CommandEvent(self, room, event_id, sender, command, args, is_management, is_portal)
         orig_command = command
         command = command.lower()

setup.cfg

@@ -0,0 +1,2 @@
+[aliases]
+test=pytest

setup.py

@@ -44,6 +44,9 @@ setuptools.setup(
     ],
     extras_require=extras,
 
+    setup_requires=["pytest-runner"],
+    tests_require=["pytest", "pytest-asyncio", "pytest-mock"],
+
     classifiers=[
         "Development Status :: 4 - Beta",
         "License :: OSI Approved :: GNU Affero General Public License v3 or later (AGPLv3+)",

tests/commands/test_handler.py

@@ -0,0 +1,394 @@
+from typing import Tuple
+from unittest.mock import Mock
+
+import pytest
+from _pytest.fixtures import FixtureRequest
+from pytest_mock import MockFixture
+
+import mautrix_telegram.commands.handler
+from mautrix_telegram.commands.handler import (
+    CommandEvent, CommandHandler, CommandProcessor, HelpSection
+)
+from mautrix_telegram.config import Config
+from mautrix_telegram.context import Context
+from mautrix_telegram.types import MatrixEventID, MatrixRoomID, MatrixUserID
+import mautrix_telegram.user as u
+
+from tests.utils.helpers import AsyncMock, list_true_once_each
+
+
+@pytest.fixture
+def context(request: FixtureRequest) -> Context:
+    """Returns a Context with mocked Attributes.
+
+    Uses the attribute cls.config as Config.
+    """
+    # Config(path, registration_path, base_path)
+    config = getattr(request.cls, 'config', Config("", "", ""))
+    return Context(
+        Mock(),  # az
+        Mock(),  # db
+        config,  # config
+        Mock(),  # loop
+        Mock()  # session_container
+    )
+
+
+@pytest.fixture
+def command_processor(context: Context) -> CommandProcessor:
+    """Returns a mocked CommandProcessor."""
+    return CommandProcessor(context)
+
+
+class TestCommandEvent:
+    config = Config("", "", "")
+    config["bridge.command_prefix"] = "tg"
+    config["bridge.permissions"] = {"*": "noperm"}
+
+    def test_reply(
+        self, command_processor: CommandProcessor, mocker: MockFixture
+    ) -> None:
+        mocker.patch("mautrix_telegram.user.config", self.config)
+
+        evt = CommandEvent(
+            processor=command_processor,
+            room=MatrixRoomID("#mock_room:example.org"),
+            event=MatrixEventID("$H45H:example.org"),
+            sender=u.User(MatrixUserID("@sender:example.org")),
+            command="help",
+            args=[],
+            is_management=True,
+            is_portal=False,
+        )
+
+        mock_az = command_processor.az
+
+        message = "**This** <i>was</i><br/><strong>all</strong>fun*!"
+
+        # html, no markdown
+        evt.reply(message, allow_html=True, render_markdown=False)
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "**This** <i>was</i><br/><strong>all</strong>fun*!",
+            html="**This** <i>was</i><br/><strong>all</strong>fun*!\n",
+        )
+
+        # html, markdown (default)
+        evt.reply(message, allow_html=True, render_markdown=True)
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "**This** <i>was</i><br/><strong>all</strong>fun*!",
+            html=(
+                "<p><strong>This</strong> <i>was</i><br/>"
+                "<strong>all</strong>fun*!</p>\n"
+            ),
+        )
+
+        # no html, no markdown
+        evt.reply(message, allow_html=False, render_markdown=False)
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "**This** <i>was</i><br/><strong>all</strong>fun*!",
+            html=None,
+        )
+
+        # no html, markdown
+        evt.reply(message, allow_html=False, render_markdown=True)
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "**This** <i>was</i><br/><strong>all</strong>fun*!",
+            html=(
+                "<p><strong>This</strong> &lt;i&gt;was&lt;/i&gt;&lt;br/&gt;"
+                "&lt;strong&gt;all&lt;/strong&gt;fun*!</p>\n"
+            ),
+        )
+
+    def test_reply_with_cmdprefix(
+        self, command_processor: CommandProcessor, mocker: MockFixture
+    ) -> None:
+        mocker.patch("mautrix_telegram.user.config", self.config)
+
+        evt = CommandEvent(
+            processor=command_processor,
+            room=MatrixRoomID("#mock_room:example.org"),
+            event=MatrixEventID("$H45H:example.org"),
+            sender=u.User(MatrixUserID("@sender:example.org")),
+            command="help",
+            args=[],
+            is_management=False,
+            is_portal=False,
+        )
+
+        mock_az = command_processor.az
+
+        evt.reply(
+            "$cmdprefix+sp ....$cmdprefix+sp...$cmdprefix $cmdprefix",
+            allow_html=False,
+            render_markdown=False,
+        )
+
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "tg ....tg+sp...tg tg",
+            html=None,
+        )
+
+    def test_reply_with_cmdprefix_in_management_room(
+        self, command_processor: CommandProcessor, mocker: MockFixture
+    ) -> None:
+        mocker.patch("mautrix_telegram.user.config", self.config)
+
+        evt = CommandEvent(
+            processor=command_processor,
+            room=MatrixRoomID("#mock_room:example.org"),
+            event=MatrixEventID("$H45H:example.org"),
+            sender=u.User(MatrixUserID("@sender:example.org")),
+            command="help",
+            args=[],
+            is_management=True,
+            is_portal=False,
+        )
+
+        mock_az = command_processor.az
+
+        evt.reply(
+            "$cmdprefix+sp ....$cmdprefix+sp...$cmdprefix $cmdprefix",
+            allow_html=True,
+            render_markdown=True,
+        )
+
+        mock_az.intent.send_notice.assert_called_with(
+            MatrixRoomID("#mock_room:example.org"),
+            "....tg+sp...tg tg",
+            html="<p>....tg+sp...tg tg</p>\n",
+        )
+
+class TestCommandHandler:
+    config = Config("", "", "")
+    config["bridge.permissions"] = {"*": "noperm"}
+
+    @pytest.mark.parametrize(
+        (
+            "needs_auth,"
+            "needs_puppeting,"
+            "needs_matrix_puppeting,"
+            "needs_admin,"
+            "management_only,"
+        ),
+        [l for l in list_true_once_each(length=5)]
+    )
+    @pytest.mark.asyncio
+    async def test_permissions_denied(
+        self,
+        needs_auth: bool,
+        needs_puppeting: bool,
+        needs_matrix_puppeting: bool,
+        needs_admin: bool,
+        management_only: bool,
+        command_processor: CommandProcessor,
+        boolean: bool,
+        mocker: MockFixture,
+    ) -> None:
+        mocker.patch("mautrix_telegram.user.config", self.config)
+
+        command = "testcmd"
+
+        mock_handler = Mock()
+
+        command_handler = CommandHandler(
+            handler=mock_handler,
+            needs_auth=needs_auth,
+            needs_puppeting=needs_puppeting,
+            needs_matrix_puppeting=needs_matrix_puppeting,
+            needs_admin=needs_admin,
+            management_only=management_only,
+            name=command,
+            help_text="No real command",
+            help_args="mock mockmock",
+            help_section=HelpSection("Mock Section", 42, ""),
+        )
+
+        sender = u.User(MatrixUserID("@sender:example.org"))
+        sender.puppet_whitelisted = False
+        sender.matrix_puppet_whitelisted = False
+        sender.is_admin = False
+
+        event = CommandEvent(
+            processor=command_processor,
+            room=MatrixRoomID("#mock_room:example.org"),
+            event=MatrixEventID("$H45H:example.org"),
+            sender=sender,
+            command=command,
+            args=[],
+            is_management=False,
+            is_portal=boolean,
+        )
+
+        assert await command_handler.get_permission_error(event)
+        assert not command_handler.has_permission(False, False, False, False, False)
+
+    @pytest.mark.parametrize(
+        (
+            "is_management,"
+            "puppet_whitelisted,"
+            "matrix_puppet_whitelisted,"
+            "is_admin,"
+            "is_logged_in,"
+        ),
+        [l for l in list_true_once_each(length=5)]
+    )
+    @pytest.mark.asyncio
+    async def test_permission_granted(
+        self,
+        is_management: bool,
+        puppet_whitelisted: bool,
+        matrix_puppet_whitelisted: bool,
+        is_admin: bool,
+        is_logged_in: bool,
+        command_processor: CommandProcessor,
+        boolean: bool,
+        mocker: MockFixture,
+    ) -> None:
+        mocker.patch("mautrix_telegram.user.config", self.config)
+
+        command = "testcmd"
+
+        mock_handler = Mock()
+
+        command_handler = CommandHandler(
+            handler=mock_handler,
+            needs_auth=False,
+            needs_puppeting=False,
+            needs_matrix_puppeting=False,
+            needs_admin=False,
+            management_only=False,
+            name=command,
+            help_text="No real command",
+            help_args="mock mockmock",
+            help_section=HelpSection("Mock Section", 42, ""),
+        )
+
+        sender = u.User(MatrixUserID("@sender:example.org"))
+        sender.puppet_whitelisted = puppet_whitelisted
+        sender.matrix_puppet_whitelisted = matrix_puppet_whitelisted
+        sender.is_admin = is_admin
+        mocker.patch.object(u.User, 'is_logged_in', return_value=is_logged_in)
+
+        event = CommandEvent(
+            processor=command_processor,
+            room=MatrixRoomID("#mock_room:example.org"),
+            event=MatrixEventID("$H45H:example.org"),
+            sender=sender,
+            command=command,
+            args=[],
+            is_management=is_management,
+            is_portal=boolean,
+        )
+
+        assert not await command_handler.get_permission_error(event)
+        assert command_handler.has_permission(
+            is_management=is_management,
+            puppet_whitelisted=puppet_whitelisted,
+            matrix_puppet_whitelisted=matrix_puppet_whitelisted,
+            is_admin=is_admin,
+            is_logged_in=is_logged_in,
+        )
+
+
+class TestCommandProcessor:
+    config = Config("", "", "")
+    config["bridge.command_prefix"] = "tg"
+    config["bridge.permissions"] = {"*": "relaybot"}
+
+    @pytest.mark.asyncio
+    async def test_handle(
+            self,
+            command_processor: CommandProcessor,
+            boolean2: Tuple[bool, bool],
+            mocker: MockFixture,
+        ) -> None:
+        mocker.patch('mautrix_telegram.user.config', self.config)
+        mocker.patch(
+            'mautrix_telegram.commands.handler.command_handlers',
+            {"help": AsyncMock(), "unknown-command": AsyncMock()}
+        )
+
+        sender = u.User(MatrixUserID("@sender:example.org"))
+
+        result = await command_processor.handle(
+            room=MatrixRoomID("#mock_room:example.org"),
+            event_id=MatrixEventID("$H45H:example.org"),
+            sender=sender,
+            command="hElp",
+            args=[],
+            is_management=boolean2[0],
+            is_portal=boolean2[1],
+        )
+
+        assert result is None
+        command_handlers = mautrix_telegram.commands.handler.command_handlers
+        command_handlers["help"].mock.assert_called_once()  # type: ignore
+
+    @pytest.mark.asyncio
+    async def test_handle_unknown_command(
+        self,
+        command_processor: CommandProcessor,
+        boolean2: Tuple[bool, bool],
+        mocker: MockFixture,
+    ) -> None:
+        mocker.patch('mautrix_telegram.user.config', self.config)
+        mocker.patch(
+            'mautrix_telegram.commands.handler.command_handlers',
+            {"help": AsyncMock(), "unknown-command": AsyncMock()}
+        )
+
+        sender = u.User(MatrixUserID("@sender:example.org"))
+        sender.command_status = {}
+
+        result = await command_processor.handle(
+            room=MatrixRoomID("#mock_room:example.org"),
+            event_id=MatrixEventID("$H45H:example.org"),
+            sender=sender,
+            command="foo",
+            args=[],
+            is_management=boolean2[0],
+            is_portal=boolean2[1],
+        )
+
+        assert result is None
+        command_handlers = mautrix_telegram.commands.handler.command_handlers
+        command_handlers["help"].mock.assert_not_called()  # type: ignore
+        command_handlers["unknown-command"].mock.assert_called_once()  # type: ignore
+
+    @pytest.mark.asyncio
+    async def test_handle_delegated_handler(
+        self,
+        command_processor: CommandProcessor,
+        boolean2: Tuple[bool, bool],
+        mocker: MockFixture,
+    ) -> None:
+        mocker.patch('mautrix_telegram.user.config', self.config)
+        mocker.patch(
+            'mautrix_telegram.commands.handler.command_handlers',
+            {"help": AsyncMock(), "unknown-command": AsyncMock()}
+        )
+
+        sender = u.User(MatrixUserID("@sender:example.org"))
+        sender.command_status = {"foo": AsyncMock(), "next": AsyncMock()}
+
+        result = await command_processor.handle(
+            room=MatrixRoomID("#mock_room:example.org"),
+            event_id=MatrixEventID("$H45H:example.org"),
+            sender=sender,  # u.User
+            command="foo",
+            args=[],
+            is_management=boolean2[0],
+            is_portal=boolean2[1]
+        )
+
+        assert result is None
+        command_handlers = mautrix_telegram.commands.handler.command_handlers
+        command_handlers["help"].mock.assert_not_called()  # type: ignore
+        command_handlers["unknown-command"].mock.assert_not_called()  # type: ignore
+        sender.command_status["foo"].mock.assert_not_called()  # type: ignore
+        sender.command_status["next"].mock.assert_called_once()  # type: ignore

tests/conftest.py

@@ -0,0 +1,3 @@
+pytest_plugins = [
+    "tests.utils.fixtures",
+]

tests/utils/fixtures.py

@@ -0,0 +1,30 @@
+"""This module provides utility fixtures for testing."""
+from typing import Tuple
+
+from _pytest.fixtures import FixtureRequest
+import pytest
+
+
+@pytest.fixture(params=[True, False])
+def boolean(request: FixtureRequest) -> bool:
+    return request.param
+
+
+@pytest.fixture
+def boolean1(boolean: bool) -> Tuple[bool]:
+    return (boolean,)
+
+
+@pytest.fixture(params=[True, False])
+def boolean2(request: FixtureRequest, boolean: bool) -> Tuple[bool, bool]:
+    return (boolean, request.param)
+
+
+@pytest.fixture(params=[True, False])
+def boolean3(
+    request: FixtureRequest, boolean2: Tuple[bool, bool]
+) -> Tuple[bool, bool, bool]:
+    return (boolean2[0], boolean2[1], request.param)
+
+
+# …

tests/utils/helpers.py

@@ -0,0 +1,24 @@
+"""This module provides utility functions for testing."""
+from typing import Generator, Tuple
+from unittest.mock import Mock
+
+
+def AsyncMock(*args, **kwargs):
+    """Mocks a asyncronous coroutine which can be called with 'await'."""
+    m = Mock(*args, **kwargs)
+
+    async def mock_coro(*args, **kwargs):
+        return m(*args, **kwargs)
+
+    mock_coro.mock = m
+    return mock_coro
+
+
+def list_true_once_each(length: int) -> Generator[Tuple[bool, ...], None, None]:
+    """Yields tuples of bools with exactly one entry being True, starting left.
+
+    Args:
+        length: Length of the resulting tuples
+    """
+    for i in range(length):
+        yield tuple(i == j for j in range(length))