tee: merge logic of flush into write

[oech3]

We always flush() after write. So we don't need 2 functions.
Closes #11893 .

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/timeout/timeout-group. tests/timeout/timeout-group is passing on 'main'. Maybe you have to rebase?
Skip an intermittent issue tests/pr/bounded-memory (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/tail-n0f (fails in this run but passes in the 'main' branch)
Congrats! The gnu test tests/printf/printf-surprise is now passing!

[codspeed-hq]

Too many benchmarks in a single upload

The performance report could not be generated because there were too many benchmarks in a single upload to CodSpeed. We recommend sharding your benchmarks into smaller uploads, with max 1000 benchmarks per upload. See the documentation for more information.

[oech3]

I think usize returned by write_all is not used at anywhere.

[xtqqczze]

I've incorporated these changed into #11893

[oech3]

Is it able to reduce 15 lines at your PR?

[xtqqczze]

@codspeedbot why have we started getting "Too many benchmarks in a single upload" error when number of benchmarks haven't changed?

[codspeed-hq]

@codspeedbot why have we started getting "Too many benchmarks in a single upload" error when number of benchmarks haven't changed?

Based on my investigation, here's what I found:

Your repository currently has 310 benchmarks in total (155 unique benchmarks × 2 modes: simulation + memory), spread across 62 matrix jobs (31 packages × 2 modes). Each individual shard contains only 5–20 benchmarks, which is well under the 1,000 per-upload recommendation.

Looking at recent CodSpeed runs for this repository:

• The latest push to main completed successfully with all 310 benchmarks
• PR chmod: fix TOCTOU race in recursive traversal #11918, PR benchmarks.yml: reduce benches #11916, PR ls: ls -lF symlink target indicators #11554, and PR cat: avoid unnecessary alloc on Linux #11906 all completed successfully with the same benchmark configuration
• PR tee: merge logic of flush into write #11893 (the related tee PR) and this PR failed with the "Too many benchmarks" error

Since the same benchmark configuration succeeds for some runs and fails for others — and the total count is far below the 1,000 limit — this is an intermittent issue on the CodSpeed platform side, not a problem with your repository configuration.

I've flagged this for the CodSpeed engineering team to investigate. In the meantime, re-running the benchmark workflow should resolve the error for this PR.

Summary

• Warming up the performance wizard...
• Investigating CodSpeed error — Analysis complete. The benchmark count (310 total) is well within limits. This appears to be a platform-side intermittent issue.
• Handling comment — Comment handling finished successfully

[cakebaker]

Hm, I'm confused. Do I understand it correctly that this PR is a spin-off from #11893 and should be merged before #11893?

[oech3]

11893 was trying to dedup write and flush previously and use match and not merging flush. This merges flush only and I don't want to use match.

[xtqqczze]

This pattern is unidiomatic, see #11919

[oech3]

Would you provide more detail?

[xtqqczze]

Specifically the unused arg for and_then

[oech3]

But this very reasonable way to chain flush. Is there any alternative without a bunch of dupes?

[xtqqczze]

See #11893

[oech3]

let res = (|| {
    writer.write_all(buf)?;
    writer.flush()?;
    Ok(())
})();

is long...

[xtqqczze]

Can be reduced to:

(|| {
    writer.write_all(buf)?;
    writer.flush()
})()

Once try_blocks are stabilised, this becomes cleaner:

try {
    writer.write_all(buf)?;
    writer.flush()?;
}

[oech3]

Can we keep chain with the form?

[GuillaumeLagrange]

@codspeedbot why have we started getting "Too many benchmarks in a single upload" error when number of benchmarks haven't changed?

@xtqqczze the codspeed failures are due to something that changed on our end. We have temporarily reverted the changes while we fix the issue. Retrying your runs should now succeed. Sorry for this

[codspeed-hq]

@codspeedbot why have we started getting "Too many benchmarks in a single upload" error when number of benchmarks haven't changed?

@xtqqczze the codspeed failures are due to something that changed on our end. We have temporarily reverted the changes while we fix the issue. Retrying your runs should now succeed. Sorry for this

This comment is an informational update from the CodSpeed team — no code or configuration changes are needed in the repository.

To summarize for @xtqqczze: the "Too many benchmarks in a single upload" error was caused by a temporary change on the CodSpeed platform side and has since been reverted. Re-running the CI workflows on this PR should now produce the performance report successfully.

Summary

• Warming up the performance wizard...
• Assessing request — No action needed — this is an informational update, not an actionable request
• Handling comment — Comment handling finished successfully

[cakebaker]

@GuillaumeLagrange thanks for the quick "fix"!

[oech3]

@xtqqczze Ok. @cakebaker Please ignore this PR and merge #11893 . Sorry for confusing you.