Revert to prompt_toolkit's background task cleanup

CHANGELOG.rst

@@ -11,6 +11,7 @@ Upcoming
 Fixed
 =====
 
+- Prevent ``background_tasks`` error with ``prompt_toolkit==3.0.30``
 - Prevent error when adding a cell during initial render
 
 ----

euporie/core/app.py

@@ -823,21 +823,6 @@ def _handle_exception(
         # Log observed exceptions to the log
         log.exception("An unhandled exception occurred", exc_info=exception)
 
-    async def cancel_and_wait_for_background_tasks(self) -> None:
-        """Cancel all background tasks, and wait for the cancellation to be done.
-
-        Ignore :py:`RuntimeError`s, which result when tasks are attached to a different
-        event loop.
-        """
-        for task in self.background_tasks:
-            task.cancel()
-
-        for task in self.background_tasks:
-            try:
-                await task
-            except (asyncio.CancelledError, RuntimeError):
-                pass
-
     # ################################### Commands ####################################
 
     @staticmethod

euporie/core/convert/formats/formatted_text.py

@@ -17,7 +17,9 @@
     from prompt_toolkit.formatted_text.base import StyleAndTextTuples
     from upath import UPath
 
-_html_cache = SimpleCache(maxsize=20)
+    from euporie.core.formatted_text.html import HTML
+
+_html_cache: "SimpleCache[int, HTML]" = SimpleCache(maxsize=20)
 
 
 @register(
@@ -36,7 +38,11 @@ def html_to_ft(
     from euporie.core.formatted_text.html import HTML
 
     html = _html_cache.get(hash(data), partial(HTML, data, width=width, base=path))
-    if html.width != width or html.height != height:
+    if (
+        width is not None
+        and height is not None
+        and (html.width != width or html.height != height)
+    ):
         html.render(width, height)
     return to_formatted_text(HTML(data, width=width, base=path))
 

scripts/show.py

@@ -1,6 +1,6 @@
 """A application to show files on the command line."""
 
-from typing import TYPE_CHECKING
+from typing import TYPE_CHECKING, cast
 
 from prompt_toolkit.application.current import set_app
 
@@ -10,7 +10,7 @@
 if TYPE_CHECKING:
     from typing import Any, Callable, Optional
 
-    from prompt_toolkit.application.base import _AppResult
+    from prompt_toolkit.application.application import _AppResult
 
 
 class ShowApp(BaseApp):
@@ -50,6 +50,7 @@ def run(
                     ),
                     style=self.create_merged_style(),
                 )
+        return cast("_AppResult", None)
 
 
 if __name__ == "__main__":