guard against no L1T uGT digis in L1TriggerResultsConverter [12_6_X]

[missirol]

backport of #40528

PR description:

This PR fixes the edge case reported in #40494. It adds a check on the size of the L1T uGT digis, returning false for all L1T algorithms when said input collection has 0 elements for the relevant BX (see #40528 (comment) for details).

PR validation:

None beyond the checks done for #40528.

If this PR is a backport, please specify the original PR and why you need to backport that PR. If this PR will be backported, please specify to which release cycle the backport is meant for:

#40528

Bugfix to NanoAOD in release cycle to be used for data-taking.

[cmsbuild]

A new Pull Request was created by @missirol (Marino Missiroli) for CMSSW_12_6_X.

It involves the following packages:

• PhysicsTools/NanoAOD (xpog)

@cmsbuild, @swertz, @vlimant can you please review it and eventually sign? Thanks.
@gpetruc this is something you requested to watch as well.
@perrotta, @dpiparo, @rappoccio you are the release manager for this.

cms-bot commands are listed here

• Backported from guard against no L1T uGT digis in L1TriggerResultsConverter #40528

[missirol]

type bugfix

[missirol]

enable nano

Not really necessary for this PR, but I understand XPOG requires this for PRs involving NanoAOD.

[missirol]

please test

[cmsbuild]

+1

Summary: https://cmssdt.cern.ch/SDT/jenkins-artifacts/pull-request-integration/PR-a4e564/30120/summary.html
COMMIT: 8f4f538
CMSSW: CMSSW_12_6_X_2023-01-22-2300/el8_amd64_gcc10
Additional Tests: NANO
User test area: For local testing, you can use /cvmfs/cms-ci.cern.ch/week1/cms-sw/cmssw/40588/30120/install.sh to create a dev area with all the needed externals and cmssw changes.

Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 8 differences found in the comparisons
• DQMHistoTests: Total files compared: 48
• DQMHistoTests: Total histograms compared: 3458651
• DQMHistoTests: Total failures: 3
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 3458626
• DQMHistoTests: Total skipped: 22
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 47 files compared)
• Checked 206 log files, 158 edm output root files, 48 DQM output files
• TriggerResults: no differences found

NANO Comparison Summary

Summary:

• No significant changes to the logs found
• Reco comparison results: 0 differences found in the comparisons
• DQMHistoTests: Total files compared: 15
• DQMHistoTests: Total histograms compared: 15414
• DQMHistoTests: Total failures: 0
• DQMHistoTests: Total nulls: 0
• DQMHistoTests: Total successes: 15414
• DQMHistoTests: Total skipped: 0
• DQMHistoTests: Total Missing objects: 0
• DQMHistoSizes: Histogram memory added: 0.0 KiB( 14 files compared)
• Checked 31 log files, 14 edm output root files, 15 DQM output files

Nano size comparison Summary:

Sample	kb/ev	ref kb/ev	diff kb/ev	ev/s/thd	ref ev/s/thd	diff rate	mem/thd	ref mem/thd
2500.31	2.209	2.209	0.000 ( +0.0% )	9.22	8.93	+3.3%	1.571	1.592
2500.311	2.329	2.329	0.000 ( +0.0% )	8.98	8.66	+3.6%	1.935	1.962
2500.312	2.284	2.284	0.000 ( +0.0% )	9.04	8.72	+3.7%	1.927	1.946
2500.33	1.096	1.096	0.000 ( +0.0% )	21.86	20.13	+8.6%	1.696	1.706
2500.331	1.396	1.396	0.000 ( +0.0% )	15.84	14.97	+5.8%	1.841	1.850
2500.332	1.328	1.328	0.000 ( +0.0% )	17.70	16.60	+6.6%	1.804	1.800
2500.4	2.097	2.097	0.000 ( +0.0% )	9.86	9.48	+3.9%	1.469	1.490
2500.401	2.164	2.164	0.000 ( +0.0% )	9.90	9.53	+3.9%	1.267	1.292
2500.5	1.668	1.668	0.000 ( +0.0% )	15.57	14.50	+7.4%	1.186	1.201
2500.501	1.729	1.729	0.000 ( +0.0% )	15.59	14.48	+7.6%	1.198	1.213
2500.51	1.071	1.071	0.000 ( +0.0% )	28.70	26.55	+8.1%	1.476	1.498
2500.511	1.137	1.137	0.000 ( +0.0% )	28.16	25.91	+8.7%	1.499	1.525
2500.6	2.006	2.006	0.000 ( +0.0% )	12.49	11.81	+5.8%	1.241	1.263
2500.601	2.076	2.076	0.000 ( +0.0% )	12.57	11.79	+6.6%	1.253	1.269

[swertz]

+1

[cmsbuild]

This pull request is fully signed and it will be integrated in one of the next CMSSW_12_6_X IBs (tests are also fine) and once validation in the development release cycle CMSSW_13_0_X is complete. This pull request will now be reviewed by the release team before it's merged. @perrotta, @dpiparo, @rappoccio (and backports should be raised in the release meeting by the corresponding L2)

[perrotta]

+1