brew/Library/Homebrew/test/cask/cli/home_spec.rb

describe Hbc::CLI::Home, :cask do
  before do
    allow(described_class).to receive(:open_url)
  end

  it "opens the homepage for the specified Cask" do
    expect(described_class).to receive(:open_url).with("http://example.com/local-caffeine")
    described_class.run("local-caffeine")
  end

  it "works for multiple Casks" do
    expect(described_class).to receive(:open_url).with("http://example.com/local-caffeine")
    expect(described_class).to receive(:open_url).with("http://example.com/local-transmission")
    described_class.run("local-caffeine", "local-transmission")
  end

  it "opens the project page when no Cask is specified" do
    expect(described_class).to receive(:open_url).with("https://caskroom.github.io/")
    described_class.run
  end
end