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@AA-Turner Can you check if the results are consistent on Windows as well please?

Here is what I suggest:

• For 3.14, we can fix the regression (I will consider it a bug) if this reproduces on multiple systems. We might have other things at play here depending on where Python is built.
• For 3.15, we can uselazy imports to make it cleaner if necessary.

I will also try to check what happens on older systems (openSUSE + older GCC/clang).

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Yeah I didn't uselazy import to cater for backports. Would you prefer thelazy import version to be in this fix PR, or in a follow-up?

For now, let's check whether the regression is consistent across platforms.

For now, let's check whether the regression is consistent across platforms.

It is, and also it's really a complexity change.shlex.quote('a ' + 'b' * N) will always be slower in 3.14+ if you make N high enough. (And in practice, 10 is enough to have a substantial effect).

What I want to know is why Adam reported numbers that went in the other direction. Ideally I also want to know the stdev of the numbers usingpyperf (which I will do this w-e)

I suggested in#132036 (comment) to replace there callif we had something more efficient, and Adam found out that it was faster usingbytes.translate so I'd like to know which data it was tested on:

With this, we go from ~26 microseconds for quote to ~2 (with only safe characters) and ~6 (with characters needing quotation).