Avoid truncation when truncating means longer output

[Pierre-Sassoulas]

The full output of a test is no longer truncated if the truncation message would be longer than
the hidden text. The line number shown has also been fixed.

I also used f-string for faster string formatting in a previous commit, I don't think this warrant another MR though.

Closes #6267

[Pierre-Sassoulas]

@nicoddemus anything I can do to make the review easier ? :)

[nicoddemus]

Hi @Pierre-Sassoulas, sorry for the delay and thanks for the ping.

LGTM, left a few small comments, please take a look. 👍

[nicoddemus]

I think this file would be better marked as improvement in the changelog, so can you please rename it to 6267.improvement.rst?

[Pierre-Sassoulas]

Done in e7a48a2

[nicoddemus]

Shouldn't you use truncated_explanation here?

Suggested change

	if len("".join(input_lines)) > tolerable_max_chars:
	if len("".join(truncated_explanation)) > tolerable_max_chars:

[nicoddemus]

If so, probably best to update the comment above:

# We reevaluate the need to truncate chars following removal of some lines

[Pierre-Sassoulas]

Nice catch ! This led to further improvement in 4d2c40f

[Pierre-Sassoulas]

I can cleanup the history and rebase if you want. I'm not sure if the current fail from the CI is due to my changes, so maybe rebasing would help ?

`tox.tox_env.errors.Fail: pass_env values cannot contain whitespace, use comma to have multiple values in a single line, invalid values found 'GH_RELEASE_NOTES_TOKEN GITHUB_REF GITHUB_REPOSITORY

[nicoddemus]

I can cleanup the history and rebase if you want. I'm not sure if the current fail from the CI is due to my changes, so maybe rebasing would help ?

The failure will be fixed in #10578, once we merge that don't worry that we can rebase this PR. 👍

[nicoddemus]

Thanks @Pierre-Sassoulas!

LGTM, great work! I will leave this up for a few more days in case anybody else wants to review it.

[nicoddemus]

@Pierre-Sassoulas main has been fixed in #10578, could you please rebase or enable maintainers to push to your fork? I did rebase but could not push --force to your fork. 👍

[Pierre-Sassoulas]

Strange, "allow edit by maintainer" is checked. I rebased, I'm going to check the macos fail later today :)

[nicoddemus]

I triggered the job again, and now it passed, so it seems like it was a flaky error, so do not worry.