Re: [PATCH 2/3] trace2: trim whitespace in start message in perf target format

Jeff Hostetler [off-list ref] writes:

On 8/1/2019 5:34 PM, Junio C Hamano wrote:

quoted

"Jeff Hostetler via GitGitGadget" [off-list ref] writes:

quoted

From: Jeff Hostetler <redacted>

Trim leading/trailing whitespace from the command line
printed in the "start" message in the perf target format.

We use `sq_quote_argv_pretty()` to format the message
and it adds a leading space to the output.  Trim that.

strbuf_trim() not just drops a single leading space, but removes
consecutive spaces from both ends.  But the first char after the SP
comes from the first arg, and it can never be a whitespace (as a
payload that begins with a whitespace will be quoted, so it will be
a single quote), and the last char in the buffer would also be
either a closing single quote (if the last argument ends with a
whitespace) or a non whitespace "safe" character, so it is safe to
use strbuf_trim() here.

I wonder if we want to lose the prepending of SP from
sq_quote_argv_pretty(), though:

I was wondering about that too, but I didn't want to presume
to know what all of the callers wanted.  And didn't want to
slip in such a change last-minute.

I do not think this topic/discussion is a place to do so, either.
And compensating on the caller's side, like your patch did, is
perfectly fine.

I was more disturbed by potential double quoting in some codepaths
when I did a cursory audit of users of sq_quote_argv_pretty(), and
would think that would be of more importance, though.