This commit adds a sys.implementation.mpy entry when the system supports
importing .mpy files. This entry is a 16-bit integer which encodes two
bytes of information from the header of .mpy files that are supported by
the system being run: the second and third bytes, .mpy version, and flags
and native architecture. This allows determining the supported .mpy file
dynamically by code, and also for the user to find it out by inspecting
this value. It's further possible to dynamically detect if the system
supports importing .mpy files by `hasattr(sys.implementation, 'mpy')`.
Replace the is_running field with a tri-state variable to indicate
running/not-running/pending-exception.
Update tests to cover the various cases.
This allows cancellation in uasyncio even if the coroutine hasn't been
executed yet. Fixes#5242
Prior to this commit, when unwinding through an active finally the stack
was not being correctly popped/folded, which resulting in the VM crashing
for complicated unwinding of nested finallys.
This should be fixed with this commit, and more tests for return/break/
continue within a finally have been added to exercise this.
Prior to this patch mp_opcode_format would calculate the incorrect size of
the MP_BC_UNWIND_JUMP opcode, missing the additional byte. But, because
opcodes below 0x10 are unused and treated as bytes in the .mpy load/save
and freezing code, this bug did not show any symptoms, since nested unwind
jumps would rarely (if ever) reach a depth of 16 (so the extra byte of this
opcode would be between 0x01 and 0x0f and be correctly loaded/saved/frozen
simply as an undefined opcode).
This patch fixes this bug by correctly accounting for the additional byte.
.
With this patch alignment is done relative to the start of the buffer that
is being unpacked, not the raw pointer value, as per CPython.
Fixes issue #3314.
Prior to this patch the amount of free space in an array (including
bytearray) was not being maintained correctly for the case of slice
assignment which changed the size of the array. Under certain cases (as
encoded in the new test) it was possible that the array could grow beyond
its allocated memory block and corrupt the heap.
Fixes issue #4127.
Reuse the implementation for bytes since it works the same way regardless
of the underlying type. This method gets added for CPython compatibility
of bytearray, but to keep the code simple and small array.array now also
has a working decode method, which is non-standard but doesn't hurt.
This allows figuring out the number of bytes in the memoryview object as
len(memview) * memview.itemsize.
The feature is enabled via MICROPY_PY_BUILTINS_MEMORYVIEW_ITEMSIZE and is
disabled by default.
This patch fixes a bug in the VM when breaking within a try-finally. The
bug has to do with executing a break within the finally block of a
try-finally statement. For example:
def f():
for x in (1,):
print('a', x)
try:
raise Exception
finally:
print(1)
break
print('b', x)
f()
Currently in uPy the above code will print:
a 1
1
1
segmentation fault (core dumped) micropython
Not only is there a seg fault, but the "1" in the finally block is printed
twice. This is because when the VM executes a finally block it doesn't
really know if that block was executed due to a fall-through of the try (no
exception raised), or because an exception is active. In particular, for
nested finallys the VM has no idea which of the nested ones have active
exceptions and which are just fall-throughs. So when a break (or continue)
is executed it tries to unwind all of the finallys, when in fact only some
may be active.
It's questionable whether break (or return or continue) should be allowed
within a finally block, because they implicitly swallow any active
exception, but nevertheless it's allowed by CPython (although almost never
used in the standard library). And uPy should at least not crash in such a
case.
The solution here relies on the fact that exception and finally handlers
always appear in the bytecode after the try body.
Note: there was a similar bug with a return in a finally block, but that
was previously fixed in b735208403
All exceptions that unwind through the async-with must be caught and
BaseException is the top-level class, which includes Exception and others.
Fixes issue #4552.
Instead of assuming that the method is a bytecode object, and only
supporting load of __name__, make the operation generic by delegating the
load to the method object itself. Saves a bit of code size and fixes the
case of attempting to load __name__ on a native method, see issue #4028.
This ensures that implicit variables are only converted to implicit
closed-over variables (nonlocals) at the very end of the function scope.
If variables are closed-over when first used (read from, as was done prior
to this commit) then this can be incorrect because the variable may be
assigned to later on in the function which means they are just a plain
local, not closed over.
Fixes issue #4272.
Part of this test was trying to test some functionality of __getattribute__
but this method name was misspelt so it wasn't doing anything useful.
Fixing the typo in this name makes the test fail because MicroPython
doesn't support user defined __getattribute__ methods. So this part of the
test is removed. The remaining tests are modified slightly to make it
clearer what they are testing.
This makes these special methods have the same calling behaviour as other
methods in a class instance (mp_convert_member_lookup() is already called
by mp_obj_class_lookup()).
mp_make_raise_obj must be used to convert a possible exception type to an
instance object, otherwise the VM may raise a non-exception object.
An existing test is adjusted to test this case, with the original test
already moved to generator_throw.py.
This commit implements PEP479 which disallows raising StopIteration inside
a generator to signal that it should be finished. Instead, the generator
should simply return when it is complete.
See https://www.python.org/dev/peps/pep-0479/ for details.
If bytearray is constructed from str, a second argument of encoding is
required (in CPython), and third arg of Unicode error handling is allowed,
e.g.:
bytearray("str", "utf-8", "strict")
This is similar to bytes:
bytes("str", "utf-8", "strict")
This patch just allows to pass 2nd/3rd arguments to bytearray, but
doesn't try to validate them to not impact code size. (This is also
similar to how bytes constructor is handled, though it does a bit
more validation, e.g. check that in case of str arg, encoding argument
is passed.)
The native emitter keeps the current exception in a slot in its C stack
(instead of on its Python value stack), so when it catches an exception it
must explicitly clear that slot so the same exception is not reraised later
on.
Back in 8047340d75 basic support was added in
the VM to handle return statements within a finally block. But it didn't
cover all cases, in particular when some finally's were active and others
inactive when the "return" was executed.
This patch adds further support for return-within-finally by correctly
managing the currently_in_except_block flag, and should fix all cases. The
main point is that finally handlers remain on the exception stack even if
they are active (currently being executed), and the unwind return code
should only execute those finally's which are inactive.
New tests are added for the cases which now pass.
PEP479 (see https://www.python.org/dev/peps/pep-0479/) prohibited raising
StopIteration from within a generator (it is turned into a RuntimeError).
This behaviour was introduced in Python 3.5 and in 3.7 was made compulsory.
Until uPy implements PEP479, this patch adds .py.exp files for the relevant
tests so they can be run under Python 3.7.
