Hanami has builtin facilities for routing unit tests.

Path Generation

We can assert the generated routes, to do so, we’re gonna create a spec file for the purpose. Web.routes is the class that holds all the routes for the application named Web.

It exposes a method to generate a path, which takes the name of a route as a symbol. Here’s how to test it.

# spec/web/routes_spec.rb
RSpec.describe Web.routes do
  it 'generates "/"' do
    actual = described_class.path(:root)
    expect(actual).to eq('/')
  end
  it 'generates "/books/23"' do
    actual = described_class.path(:book, id: 23)
    expect(actual).to eq('/books/23')
  end
end

Route Recognition

We can also do the opposite: starting from a fake Rack env, we can assert that the recognized route is correct.

# spec/web/routes_spec.rb
RSpec.describe Web.routes do
  # ...
  it 'recognizes "GET /"' do
    env   = Rack::MockRequest.env_for('/')
    route = described_class.recognize(env)
    expect(route.routable?).to be(true)
    expect(route.path).to   eq('/')
    expect(route.verb).to   eq('GET')
    expect(route.params).to eq({})
  end
  it 'recognizes "PATCH /books/23"' do
    env   = Rack::MockRequest.env_for('/books/23', method: 'PATCH')
    route = described_class.recognize(env)
    expect(route.routable?).to be(true)
    expect(route.path).to   eq('/books/23')
    expect(route.verb).to   eq('PATCH')
    expect(route.params).to eq(id: '23')
  end
  it 'does not recognize unknown route' do
    env   = Rack::MockRequest.env_for('/foo')
    route = subject.recognize(env)
    expect(route.routable?).to be(false)
  end
end

When we use .recognize, the router returns a recognized route, which is an object designed only for testing purposes. It carries on all the important information about the route that we have hit.