```ruby
require 'spec_helper'

describe UsersController do
  describe "GET 'show'" do
    it "returns http success" do
      get :show, username: 'test'
      response.should be_success
    end
  end
end
```

Create user before performing show action
user
```ruby
require 'spec_helper'

describe UsersController do
  describe "GET 'show'" do
    it "returns http success" do
      user = create(:user)
      get :show, username: user.username
      response.should be_success
    end
  end
end
```
assistant