Minitest::AssertErrors

Adds Minitest assertions to test for errors raised or not raised by Minitest itself. Most useful when testing other Minitest assertions or as a shortcut to other tests.

Added Methods

Currently adds the following methods:

Minitest::Assertions

assert_have_error() - also aliased as assert_error_raised()
assert_no_error() - also aliased as :refute_error()

Minitest::Expectations - for use with Minitest::Spec

actual.must_have_error(expected_msg)
actual.wont_have_error

Installation

Add this line to your application's Gemfile:

gem 'minitest-assert_errors'

And then execute:

bundle

Or install it yourself as:

gem install minitest-assert_errors

Usage

Add the gem to your Gemfile or .gemspec file and then load the gem in your (test|spec)_helper.rb file as follows:

 # <snip...>

 require 'minitest/autorun'

 require 'minitest/assert_errors'

 # <snip...>

Adding the above to your spec_helper.rb file automatically adds the key helper methods to the Minitest::Assertions to test for Minitest errors raised or not raised within your tests.

Examples

`assert_have_error(expected_msg, klass = Minitest::Assertion, &blk)`

-- also aliased as: assert_error_raised()

Assertion method to test for an error raised by Minitest

  assert_have_error('error message') { assert(false, 'error message') }

  # or

  proc {
    assert(false, 'error message')
  }.must_have_error('error message')

Produces a longer error message, combining the given error message with the default error message, when something is wrong.

NOTE! The expected error message can be a String or Regexp.

  assert_have_error(/error message.+Actual:\s+\"b\"/m) do
    assert_equal('a','b', 'error message')
  end

  # or

  proc {
    assert_equal('a','b', 'error message')
  }.must_have_error(/error message.+Actual:\s+\"b\"/m)

`assert_no_error(&blk)`

-- also aliased as: refute_error() or refute_error_raised() or assert_no_error_raised()

Assertion method to test for no error being raised by Minitest test.

  assert_no_error() { assert(true, 'error message') }

  # or

  proc { assert(true) }.wont_have_error

Produces a longer error message, combining the given error message with the default error message, when something is wrong.

NOTE! The expected error message can be a String or Regexp.

 assert_no_error { assert_equal('a', :a, 'error message') }

   #=> "error message.\nExpected: \"a\"\n  Actual: :a"

 proc {
   assert_equal('a', :a, 'error message')
 }.wont_have_error

   #=> "error message.\nExpected: \"a\"\n  Actual: :a"

Dependencies

This Gem depends upon the following:

Runtime

minitest

Development & Tests

bundler (~> 1.10)
rake (~> 10.0)
minitest-rg
simplecov [optional]
rubocop [optional]

Contributing

Bug reports and pull requests are welcome on GitHub.

This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere to the Contributor Covenant code of conduct.

Note on Patches/Pull Requests

Fork the project.
Make your feature addition or bug fix in a separate branch.
Add spec tests for it. This is important so I don't break it in a future version unintentionally.
Commit, do not mess with Rakefile, version, or history.
- (if you want to have your own version, that is fine but bump version in a commit by itself I can ignore when I pull)
Send me a pull request. Bonus points for topic branches.

Development

After checking out the repo, run bundle install to install dependencies. Then, run bundle exec rake spec to run the tests.

To install this gem onto your local machine, run bundle exec rake install.

To release a new version, update the version number in version.rb, and then run bundle exec rake release, which will create a git tag for the version, push git commits and tags, and push the .gem file to rubygems.org.

Copyright

Released under the MIT License. See LICENSE for further details.