Feature: Measure Coverage with bashcov

Description

I found that measuring coverage with bashcov is actually quite simple when combined with bats and gives very helpful results. Goal is to get a cobertura coverage report and integrate it with gitlab.

Implementation ideas

test:
  scripts:
   - |
     #install ruby and bashcov dependencies
     apk add ruby
     gem install bashcov simplecov simplecov-cobertura
   - |
     # merge any existing .simplecov settings with setting the cobertura formatter
     echo '
require 'simplecov'
require 'simplecov-cobertura'

SimpleCov.formatter = SimpleCov::Formatter::CoberturaFormatter
' >> ${CI_PROJECT_DIR}/.simplecov.tmp
     mv .simplecov .simplecov.old
     cat .simplecov.tmp .simplecov.old > .simplecov
   - bashcov -- bats --report-formatter junit --output reports $BASH_BATS_OPTS $BASH_BATS_TESTS
  artifacts:
    reports:
      coverage_report:
        coverage_format: cobertura
        path: coverage/coverage.xml

bashcov can also generate html results, but for my taste the integration inside of gitlab is just all we need.