[R-package] ensure that callbacks respect verbosity from params

[jameslamb]

Contributes to #4862.
Fixes an issue introduced by #4899 .

In the R package, lightgbm(), lgb.train(), and lgb.cv() have a keyword argument verbose. #4899 added changes to ensure that that verbosity parameters passed through params took precedence over that keyword argument.

However, evaluation and and early stopping callbacks still reference that keyword argument, which can lead to inconsistent behavior where some printed messages' verbosity can only be controlled by the keyword argument.

While working on this, I also discovered another closely-related bug...parameter verbose in calls to cb_early_stop() is being passed an integer, but that value is then checked with isTRUE()...which means that no messages are ever printed from that callback.

LightGBM/R-package/R/callback.R

Line 207 in dad3915

if (isTRUE(verbose)) {

This PR proposes changes to ensure that it's possible to silence early stopping messages and evaluation messages using params.

Notes for Reviewers

This PR reduces the number of logs printed by the R package's tests from 2095 lines to 1616 lines.

sh build-cran-package --no-build-vignettes
R CMD INSTALL --with-keep.source ./lightgbm_3.3.1.99.tar.gz
cd R-package/tests
Rscript testthat.R > ../../out.log 2>&1
echo "log lines from tests: $(cat ../../out.log | wc -l)"

[jmoralez]

Very thorough tests!

[StrikerRUS]

LGTM! 👍

[StrikerRUS]

Quite strange behavior, to be honest...
Maybe remove it in v4.0.0?

[jameslamb]

I totally agree! I definitely think we should consider removing this prior to v4.0.0.

This has been in {lightgbm} since the very first version of the R package, in #168.

Wrote up a separate issue for discussion of that: #5203.

[StrikerRUS]

Thanks a lot for doing this!

[github-actions]

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