CPython doesn't allow SEEK_CUR with non-zero offset for files in text mode,
and uPy inherited this behaviour for both text and binary files. It makes
sense to provide full support for SEEK_CUR of binary-mode files in uPy, and
to do this in a minimal way means also allowing to use SEEK_CUR with
non-zero offsets on text-mode files. That seems to be a fair compromise.
This implements .pend_throw(exc) method, which sets up an exception to be
triggered on the next call to generator's .__next__() or .send() method.
This is unlike .throw(), which immediately starts to execute the generator
to process the exception. This effectively adds Future-like capabilities
to generator protocol (exception will be raised in the future).
The need for such a method arised to implement uasyncio wait_for() function
efficiently (its behavior is clearly "Future" like, and normally would
require to introduce an expensive Future wrapper around all native
couroutines, like upstream asyncio does).
py/objgenerator: pend_throw: Return previous pended value.
This effectively allows to store an additional value (not necessary an
exception) in a coroutine while it's not being executed. uasyncio has
exactly this usecase: to mark a coro waiting in I/O queue (and thus
not executed in the normal scheduling queue), for the purpose of
implementing wait_for() function (cancellation of such waiting coro
by a timeout).
The whole idea of --list-tests is that we prepare a list of tests to run
later, and currently don't have a connection to target board. Similarly
for --write-exp - only "python3" binary would be required for this operation,
not "micropython".
The idea that --list-tests would be enough to produce list of tests for
tinytest-codegen didn't work, because normal run-tests processing heavily
relies on dynamic target capabilities discovery, and test filtering happens
as the result of that.
So, approach the issue from different end - allow to specify arbitrary
filtering criteria as run-tests arguments. This way, specific filters
will be still hardcoded, but at least on a particular target's side,
instead of constant patching tinytest-codegen and/or run-tests.
Lists tests to be executed, subject to all other filters requested. This
options would be useful e.g. for scripts like tools/tinytest-codegen.py,
which currently contains hardcoded filters for particular a particular
target and can't work for multiple targets.
"Builtin" tinytest-based testsuite as employed by qemu-arm (and now
generalized by me to be reusable for other targets) performs simplified
detection of skipped tests, it treats as such tests which raised SystemExit
(instead of checking got "SKIP" output). Consequently, each "SKIP" must
be accompanied by SystemExit (and conversely, SystemExit should not be
used if test is not skipped, which so far seems to be true).
These tests involves testing allocation-free function calling, and in strict
stackless mode, it's not possible to make a function call with heap locked
(because function activation record aka frame is allocated on the heap).
Ayke van Laethem
Damien George
Paul Sokolovsky
Petr Viktorin