`echo_via_pager` not working as expected with generators

[alia5gar]

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echo_via_pager not working as expected with generators

import time def count(): for i in range(10) time.sleep(1) yield "\ncount {i}"

Expected: The output should be printed one by one
Original: The output is printed in one shot, and the screen is blank for about 10 seconds

Environment:

• Python version: 3.10
• Click version: 8.1.3

[davidism]

Your expected behavior doesn't match the intended behavior of the function.

[alia5gar]

Documentation gives a bit wrong idea

If you want to use the pager for a lot of text, especially if generating everything in advance would take a lot of time, you can pass a generator (or generator function) instead of a string:

def _generate_output():
for idx in range(50000):
yield f"Line {idx}\n"

@click.command()
def less():
click.echo_via_pager(_generate_output())

[alia5gar]

Can you share if its possible to get this behaviour
If so I can give it a try

[kdeldycke]

@alia5gar I have a fix in line at #3534 . Can you test it?