Commit Graph

5 Commits

Author SHA1 Message Date
Damien George 309dfe39e0 extmod/uasyncio: Add Task.done() method.
This is added because task.coro==None is no longer the way to detect if a
task is finished.  Providing a (CPython compatible) function for this
allows the implementation to be abstracted away.

Signed-off-by: Damien George <damien@micropython.org>
2020-12-02 12:07:06 +11:00
Damien George ca40eb0fda extmod/uasyncio: Delay calling Loop.call_exception_handler by 1 loop.
When a tasks raises an exception which is uncaught, and no other task
await's on that task, then an error message is printed (or a user function
called) via a call to Loop.call_exception_handler.  In CPython this call is
made when the Task object is freed (eg via reference counting) because it's
at that point that it is known that the exception that was raised will
never be handled.

MicroPython does not have reference counting and the current behaviour is
to deal with uncaught exceptions as early as possible, ie as soon as they
terminate the task.  But this can be undesirable because in certain cases
a task can start and raise an exception immediately (before any await is
executed in that task's coro) and before any other task gets a chance to
await on it to catch the exception.

This commit changes the behaviour so that tasks which end due to an
uncaught exception are scheduled one more time for execution, and if they
are not await'ed on by the next scheduling loop, then the exception handler
is called (eg the exception is printed out).

Signed-off-by: Damien George <damien@micropython.org>
2020-12-02 12:07:06 +11:00
Damien George 8e048d2548 all: Clean up error strings to use lowercase and change cannot to can't.
Now that error string compression is supported it's more important to have
consistent error string formatting (eg all lowercase English words,
consistent contractions).  This commit cleans up some of the strings to
make them more consistent.
2020-04-13 22:19:37 +10:00
Jim Mussared def76fe4d9 all: Use MP_ERROR_TEXT for all error messages. 2020-04-05 15:02:06 +10:00
Damien George bc009fdd62 extmod/uasyncio: Add optional implementation of core uasyncio in C.
Implements Task and TaskQueue classes in C, using a pairing-heap data
structure.  Using this reduces RAM use of each Task, and improves overall
performance of the uasyncio scheduler.
2020-03-26 01:25:45 +11:00