Bug report

Bug description:

The get_all_awaited_by() function in the remote debugging module was returning incorrect call stack information in the awaited_by relationships. Instead of showing each task's own call stack, it was showing the awaiter's call stack, making the output confusing and misleading.

Expected Behavior

Each task should show:

• Its own call stack (where the task is currently executing)
• The task ID of who is awaiting it

Actual Behavior

Each task was showing:

• The awaiter's call stack (where the awaiter is executing)
• The task's own ID (instead of the awaiter's ID)

Example

For this code:

async def foo1():
    await foo11()
async def foo11():
    await foo12()  
async def foo12():
    await asyncio.sleep(1000)  # foo1.0 task is here

async def runner():
    async with TaskGroup() as g:
        g.create_task(foo1(), name="foo1.0")
        await asyncio.sleep(1000)  # runner/Task-1 is here

Wrong output:

foo1.0: call_stack=[sleep -> runner], awaiter_id=foo1.0  # Shows runner's stack!

Correct output:

foo1.0: call_stack=[sleep -> foo12 -> foo11 -> foo1], awaiter_id=Task-1  # Shows foo1.0's own stack!

In process_single_task_node(), the code is calling parse_task_awaited_by() which traverses to the awaiter and gets the awaiter's call stack instead of the current task's call stack.

CPython versions tested on:

CPython main branch

Operating systems tested on:

Linux

Linked PRs

• gh-135371: Fix asyncio task awaited_by semantics in remote debugging #135372