Keep HTML reporter registered when MTA is unavailable

[artemry-nv]

Summary

On external clusters without a local MTA (e.g. Pre-Tyche), MTT::Mail::Init fails and the HTML reporter previously returned 0 at Init, so it was never registered and Submit/Finalize never wrote any HTML reports. This disables email delivery (sets $to=undef) but returns 1 so HTML reports are still generated on disk.

Email-sending in Submit is already guarded by if ($to), so clearing $to cleanly skips email while HTML table generation continues.

Test plan

• Container run on Pre-Tyche generates All_phase-summary.html and per-suite HTML on disk without an MTA
• Clusters with an MTA still send email reports (unchanged path)

Reported-by: Bartlomiej Pawulski bpawulski@nvidia.com

[coderabbitai]

📝 Walkthrough

Walkthrough

In MTT::Reporter::HTMLReport::Init, the error path triggered by a failed MTT::Mail::Init call now sets $to to undef, logs that email delivery is disabled, and returns 1 (success) instead of 0 (failure), allowing HTML report files to still be written to disk.

Changes

HTML Reporter Mail-Failure Fallback

Layer / File(s)	Summary
HTMLReport::Init mail-failure fallback lib/MTT/Reporter/HTMLReport.pm	When MTT::Mail::Init fails, $to is set to undef and the function now returns 1 instead of 0, keeping the HTML reporter registered and able to write reports while disabling email delivery.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Poem

🐇 When the mail server frowns and won't play,
The rabbit still hops on its way —
No email? No fuss!
HTML's a plus,
The report shall be written today! ✉️📄

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title directly matches the main change: modifying HTML reporter initialization to succeed when MTA is unavailable, allowing registration and HTML output to disk.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

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✨ Finishing Touches

📝 Generate docstrings

• Create stacked PR
• Commit on current branch

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch fix/html-reporter-no-mta

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[artemry-nv]

Validated on Pre-Tyche (SLURM job 2273616, ucx-enroot suite, aarch64 container).

With this fix, the HTML reporter stays registered despite no MTA and writes reports to disk via save_intermediate_report=1:

• All_phase-summary.html (index, shows "Enroot with Pyxis" + /opt/hpcx + image hpcx-v2.50-...-aarch64-latest-nightly)
• Test_Run-osu_micro_benchmark_one_sided-...html (611 KB, 647 tests passed)
• MPI_Install-...html, Test_Build-...html, etc.

The prior unpatched run (job 2273422) produced zero HTML files under the same configuration, confirming this is the fix.