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Code coverage

Rails#

Rspec will generate code coverage at the end of the tests.

To get the code coverage of the entire Rails codebase, you must run the full Ruby test suite. You can run the full test suite with the rspec command:

bundle exec rspec

or

bin/rspec

To get the code coverage of a single file, you can run:

bundle exec rspec spec/models/user_spec.rb

or

bin/rspec spec/models/user_spec.rb

To get the code coverage of a particular spec in a single file, append the line-number for that spec:

bundle exec rspec spec/models/user_spec.rb:24

or

bin/rspec spec/models/user_spec.rb:24

Once your tests have completed, the coverage/index.html will be regenerated with some stats concerning the overall health of our test suite including a code coverage metric.

A few things to note:

  • "Coverage" indicates whether or not the test suite runs through the code in question. It does not equate to actually testing for functionality, and shouldn’t be thought of that way.
  • Running Rspec in general will overwrite the existing coverage/index.html so, if you want to reference the results of a particular run, save a copy of the file before re-running the test suite.

To turn off coverage report generation please set environment variable COVERAGE value to false.

Preact#

Preact tests will generate code coverage at the end of the tests.

To get the code coverage of the Preact codebase, you must run the full JS test suite. You can run the full test suite with the npm task test:

npm run test

or

yarn test

Once the tests have completed, the test coverage metric will be visible in the terminal window. Please note that jest will fail if test coverage thresholds are not met.