--combined_report=lcov not working

[tingilee]

What version of rules_go are you using?

v0.35

What version of gazelle are you using?

https://github.com/bazelbuild/bazel-gazelle/archive/6d3fa1c9c7617d52c4a93f280685cde7a8206b07.zip

What version of Bazel are you using?

Build label: 6.0.0-pre.20220922.1

Does this issue reproduce with the latest releases of all the above?

What operating system and processor architecture are you using?

Any other potentially useful information about your toolchain?

What did you do?

bazel coverage --@io_bazel_rules_go//go/config:cover_format=lcov --instrumentation_filter=^// --combined_report=lcov 

What did you expect to see?

See bazel-out/_coverage/_coverage_report.dat being populated

What did you see instead?

bazel-out/_coverage/_coverage_report.dat is empty

[tingilee]

Go coverage is broken when --combined_report=lcov is supplied in external testing:

1. go_test has a go_library in the embed attribute
2. go_library needs to provide coverage_common.instrumented_files_info so getInstrumentedFiles in Bazel returns the right instrumented files

I have a proposed fix: tingilee@e68899e
However, I'm encountering failures and could use some help here:

$ bazel test //tests/...
Starting local Bazel server and connecting to it...
ERROR: /Users/jacqueline.lee/rules_go_tingilee/go/tools/coverdata/BUILD.bazel:3:16: in go_tool_library rule //go/tools/coverdata:coverdata: Multiple conflicting returned providers with key InstrumentedFilesInfo
ERROR: /Users/jacqueline.lee/rules_go_tingilee/go/tools/coverdata/BUILD.bazel:3:16: Analysis of target '//go/tools/coverdata:coverdata' failed

[tingilee]

Actually, I've just found #3294 is the fix not yet released.
I've created a PR #3344 to add tests.

[tingilee]

Master branch includes the intended solutions.