Check for implicit reexports with mypy

An implicit reexport happens, when a module imports something using
the `from ... import ...` pattern, as the imported symbol is visible
to the outside world.

This check only allows importing from these modules if the symbol is
put in `__all__` or renamed to itself using `from A import B as B`

This check revealed several fishy imports.

See https://mypy.readthedocs.io/en/latest/config_file.html#confval-implicit_reexport

Author: vlaci

pyproject.toml

@@ -59,3 +59,6 @@ addopts = "--strict-markers"
 markers = [
     "integration_test: marks tests as slow integration tests (deselect with '-m \"not integration_test\"')",
 ]
+
+[tool.mypy]
+implicit_reexport = false

src/textual_dev/previews/colors.py

@@ -1,5 +1,6 @@
+from textual._color_constants import COLOR_NAME_TO_RGB
 from textual.app import App, ComposeResult
-from textual.color import COLOR_NAME_TO_RGB, Color
+from textual.color import Color
 from textual.containers import Horizontal, Vertical, VerticalScroll
 from textual.design import ColorSystem
 from textual.widgets import Button, Footer, Label, Static, TabbedContent

src/textual_dev/service.py

@@ -9,7 +9,7 @@
 
 import msgpack
 from aiohttp import WSMsgType
-from aiohttp.abc import Request
+from aiohttp.web_request import Request
 from aiohttp.web_ws import WebSocketResponse
 from rich.console import Console
 from rich.markup import escape

tests/devtools/test_devtools_client.py

@@ -8,11 +8,8 @@
 from aiohttp.web_ws import WebSocketResponse
 from rich.console import ConsoleDimensions
 from rich.panel import Panel
-
 from textual.constants import DEVTOOLS_PORT
-from textual_dev.client import DevtoolsClient
-from textual_dev.redirect_output import DevtoolsLog
-
+from textual_dev.client import DevtoolsClient, DevtoolsLog
 from utilities.wait_for_predicate import wait_for_predicate
 
 CALLER_LINENO = 123