ci: clear previously generated files

[dbolduc]

Fixes #12587

Make the generate-libraries build a bit more hermetic by removing previously generated files. This is how I found #14519

@scotthart - my read is that the compute stuff is the old way of doing things and UPDATED_DISCOVERY_DOCUMENT=compute is the new way. You would know better.

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This change is 

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 93.58%. Comparing base (b55de81) to head (06f65cf).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #14524      +/-   ##
==========================================
- Coverage   93.58%   93.58%   -0.01%     
==========================================
  Files        2316     2316              
  Lines      206957   206957              
==========================================
- Hits       193677   193671       -6     
- Misses      13280    13286       +6     

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[coryan]

Do you think this is a fix for #12587 ?

[dbolduc]

Do you think this is a fix for #12587 ?

Yes, it is. I remember us discussing it, but I couldn't find the issue when I searched for it. Thanks.

[scotthart]

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @dbolduc)

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ci/cloudbuild/builds/generate-libraries.sh line 29 at r2 (raw file):

if [ -z "${GENERATE_GOLDEN_ONLY}" ]; then
  io::log_h2 "Removing all other previously generated files"
  git grep -l "Generated by the Codegen C++ plugin" google | xargs rm

This probably needs to also delete any generated files under the protos/ dir as well.

[dbolduc]

This probably needs to also delete any generated files under the protos/ dir as well.

Thanks, I did not think about this.

(You know more about this, but) I think the discovery to proto process depends on the existing protos to make sure we do not break backwards compatibility. If I remove the protos before regenerating them, some of the field indices change.

So I restored the code that removes obsolete compute protos.

[scotthart]

That is correct. We do need the previous generation to compare message field id numbers.

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @dbolduc)

[scotthart]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on @dbolduc)

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ci/cloudbuild/builds/generate-libraries.sh line 54 at r3 (raw file):

  rm "${newer_tmp_file}"

  io::log_h2 "Formatting and adding any new google/cloud/compute/v1/internal/common_*.proto"

IIRC, we need to format the new protos before we generate code from them because that could change line numbers in the proto files that we put in documentation links.

[dbolduc]

IIRC, we need to format the new protos before we generate code from them because that could change line numbers in the proto files that we put in documentation links.

We already format the protos a few lines down, before running the generator on generator_config.textproto, so it was redundant.

google-cloud-cpp/ci/cloudbuild/builds/generate-libraries.sh

Lines 68 to 69 in 06f65cf

	io::log_h2 "Formatting generated protos"
	git ls-files -z -- '*.proto' |

[scotthart]

Reviewable status: 0 of 1 files reviewed, 2 unresolved discussions (waiting on @dbolduc)