assertion "heap->next == NULL" failed: file "../../py/pairheap.h", line 94, function: mp_pairheap_pop

try:
    import uasyncio as asyncio
except ImportError:
    import asyncio

# Adapted from micropython-async AsyncIterable example:                                                                                                
# https://github.com/peterhinch/micropython-async/blob/master/v3/docs/TUTORIAL.md#42-asynchronous-iterators
class AsyncGenerator:
    def __init__(self, gen):
        self.gen = gen

    def __aiter__(self):
        return self

    async def __anext__(self):
        v = await self.next()
        if v is StopIteration:
            raise StopAsyncIteration
        return v

    async def next(self):
        await asyncio.sleep(0)
        try:
            if hasattr(self.gen, '__anext__'):
                return await self.gen.__anext__()
            return next(self.gen)
        except StopIteration:
            return StopIteration

# AsyncGenerator decorator.                                                                                                                    
def async_generator(func):
    def wrapper(*args, **kwargs):
        return AsyncGenerator(func(*args, **kwargs))
    return wrapper

# A normal Python async generator function with inner SYNC loop,                                                                                      
# wrapped with AsyncGenerator.                                                                                                                         
@async_generator
async def agen1():
    for i in range(10):
        yield i

# A normal Python async generator function with inner ASYNC loop,                                                                                     
# wrapped with AsyncGenerator.                                                                                                                         
@async_generator
async def agen2(agen):
    async for i in agen:
        yield i

# Consume an async generator and print each value.                                                                                                     
async def consume(gen):
    async for i in gen:
        print(i)

def go():
    run = asyncio.get_event_loop().run_until_complete

    print('# Ok')
    run(consume(agen1()))

    print('# Not Ok')
    run(consume(agen2(agen1())))

>>> go()
# Ok
0
1
2
3
4
5
6
7
8
9
# Not Ok
None
assertion "heap->next == NULL" failed: file "../../py/pairheap.h", line 94, function: mp_pairheap_pop
abort() was called at PC 0x4016a1eb on core 1

ELF file SHA256: 0000000000000000000000000000000000000000000000000000000000000000

Backtrace: 0x4008fcb3:0x3ffce300 0x4008ffd1:0x3ffce320 0x4016a1eb:0x3ffce340 0x400edf8b:0x3ffce370 0x400e3781:0x3ffce390 0x400df7a1:0x3ffce3b0 0x400df8c9:0x3ffce3d0 0x400ed011:0x3ffce3f0 0x400e390c:0x3ffce490 0x400df7a1:0x3ffce4c0 0x400ecf89:0x3ffce4e0 0x400e390c:0x3ffce580 0x400df7a1:0x3ffce5f0 0x400ecf89:0x3ffce610 0x400e390c:0x3ffce6b0 0x400df7a1:0x3ffce720 0x400ecf89:0x3ffce740 0x400e390c:0x3ffce7e0 0x400df7a1:0x3ffce840 0x400df7ca:0x3ffce860 0x40104967:0x3ffce880 0x40104b71:0x3ffce910 0x400f5d3c:0x3ffce950 0x400992f6:0x3ffce980

Rebooting...

>>> go()
# Ok
0
1
2
3
4
5
6
7
8
9
# Not Ok
0
1
2
3
4
5
6
7
8
9