May 6, 2023 · May 3, 2023 · May 3, 2023 · May 4, 2023 · May 5, 2023 · May 5, 2023
diff --git a/Lib/asyncio/tasks.py b/Lib/asyncio/tasks.py
    children = []
    nfuts = 0
    nfinished = 0
    done_futs = []
    loop = None
    outer = None  # bpo-46672
    for arg in coros_or_futures:

            nfuts += 1
            arg_to_fut[arg] = fut
            fut.add_done_callback(_done_callback)
            if fut.done():
                done_futs.append(fut)
            else:
                fut.add_done_callback(_done_callback)

        else:
            # There's a duplicate Future object in coros_or_futures.
        children.append(fut)

    outer = _GatheringFuture(children, loop=loop)
    # Run done callbacks after GatheringFuture created so any post-processing
    # can be performed at this point
    # optimization: in the special case that *all* futures finished eagerly,
    # this will effectively complete the gather eagerly, with the last
    # callback setting the result (or exception) on outer before returning it
    for fut in done_futs:
        _done_callback(fut)
    return outer


diff --git a/Misc/NEWS.d/next/Library/2023-05-03-16-50-24.gh-issue-104144.yNkjL8.rst b/Misc/NEWS.d/next/Library/2023-05-03-16-50-24.gh-issue-104144.yNkjL8.rst
 Optimize :func:`asyncio.gather` when using :func:`asyncio.eager_task_factory`
 to complete eagerly if all fututres completed eagerly.
 Avoid scheduling done callbacks for fututres that complete eagerly.
Original file line number	Diff line number	Diff line change
Expand Up		@@ -813,6 +813,7 @@ def _done_callback(fut):
		children = []
		nfuts = 0
		nfinished = 0
		done_futs = []
		loop = None
		outer = None # bpo-46672
		for arg in coros_or_futures:
Expand All		@@ -829,7 +830,10 @@ def _done_callback(fut):

		nfuts += 1
		arg_to_fut[arg] = fut
		fut.add_done_callback(_done_callback)
		if fut.done():
		done_futs.append(fut)
		else:
		fut.add_done_callback(_done_callback)

		else:
		# There's a duplicate Future object in coros_or_futures.
Expand All		@@ -838,6 +842,13 @@ def _done_callback(fut):
		children.append(fut)

		outer = _GatheringFuture(children, loop=loop)
		# Run done callbacks after GatheringFuture created so any post-processing
		# can be performed at this point
		# optimization: in the special case that all futures finished eagerly,
		# this will effectively complete the gather eagerly, with the last
		# callback setting the result (or exception) on outer before returning it
		for fut in done_futs:
		_done_callback(fut)
		return outer


Expand Down
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		Optimize :func:`asyncio.gather` when using :func:`asyncio.eager_task_factory`
		to complete eagerly if all fututres completed eagerly.
		Avoid scheduling done callbacks for fututres that complete eagerly.
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