Module: ViewComponent::TestHelpers

Included in:
SystemTestHelpers, TestCase
Defined in:
lib/view_component/test_helpers.rb

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#rendered_content ⇒ ActionView::OutputBuffer (readonly)

Returns the result of a render_inline call.

Returns:



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# File 'lib/view_component/test_helpers.rb', line 27

def rendered_content
  @rendered_content
end

Instance Method Details

#render_in_view_context ⇒ Object

Execute the given block in the view context (using instance_exec). Internally sets page to be a Capybara::Node::Simple, allowing for Capybara assertions to be used. All arguments are forwarded to the block.

render_in_view_context(arg1, arg2: nil) do |arg1, arg2:|
  render(MyComponent.new(arg1, arg2))
end

assert_text("Hello, World!")



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# File 'lib/view_component/test_helpers.rb', line 114

def render_in_view_context(...)
  @page = nil
  @rendered_content = vc_test_view_context.instance_exec(...)
  Nokogiri::HTML5.fragment(@rendered_content)
end

#render_inline(component, **args, &block) ⇒ Nokogiri::HTML5

Render a component inline. Internally sets page to be a Capybara::Node::Simple, allowing for Capybara assertions to be used:

render_inline(MyComponent.new)
assert_text("Hello, World!")

Parameters:

Returns:

  • (Nokogiri::HTML5) 


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# File 'lib/view_component/test_helpers.rb', line 39

def render_inline(component, **args, &block)
  @page = nil
  @rendered_content = vc_test_view_context.render(component, args, &block)

  fragment = Nokogiri::HTML5.fragment(@rendered_content, context: "template")
  @vc_test_view_context = nil
  fragment
end

#render_preview(name, from: __vc_test_helpers_preview_class, params: {}) ⇒ Nokogiri::HTML5

Render a preview inline. Internally sets page to be a Capybara::Node::Simple, allowing for Capybara assertions to be used:

render_preview(:default)
assert_text("Hello, World!")

Note: #rendered_preview expects a preview to be defined with the same class name as the calling test, but with Test replaced with Preview:

MyComponentTest -> MyComponentPreview etc.

In RSpec, Preview is appended to described_class.

Parameters:

  • name (String) —

    The name of the preview to be rendered.

  • from (ViewComponent::Preview) (defaults to: __vc_test_helpers_preview_class) —

    The class of the preview to be rendered.

  • params (Hash) (defaults to: {}) —

    Parameters to be passed to the preview.

Returns:

  • (Nokogiri::HTML5) 


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# File 'lib/view_component/test_helpers.rb', line 85

def render_preview(name, from: __vc_test_helpers_preview_class, params: {})
  previews_controller = __vc_test_helpers_build_controller(Rails.application.config.view_component.previews.controller.constantize)

  # From what I can tell, it's not possible to overwrite all request parameters
  # at once, so we set them individually here.
  params.each do |k, v|
    previews_controller.request.params[k] = v
  end

  previews_controller.request.params[:path] = "#{from.preview_name}/#{name}"
  previews_controller.set_response!(ActionDispatch::Response.new)
  result = previews_controller.previews

  @rendered_content = result

  Nokogiri::HTML5.fragment(@rendered_content)
end

#rendered_json ⇒ Object

JSON.parse-d component output.

render_inline(MyJsonComponent.new)
assert_equal(rendered_json["hello"], "world")



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# File 'lib/view_component/test_helpers.rb', line 62

def rendered_json
  JSON.parse(rendered_content)
end

#vc_test_controller ⇒ ActionController::Base

Access the controller used by render_inline:

test "logged out user sees login link" do
  vc_test_controller.expects(:logged_in?).at_least_once.returns(false)
  render_inline(LoginComponent.new)
  assert_selector("[aria-label='You must be signed in']")
end

Returns:

  • (ActionController::Base) 


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# File 'lib/view_component/test_helpers.rb', line 257

def vc_test_controller
  @vc_test_controller ||= __vc_test_helpers_build_controller(vc_test_controller_class)
end

#vc_test_controller_class ⇒ Object

Set the controller used by render_inline:

def vc_test_controller_class
  MyTestController
end



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# File 'lib/view_component/test_helpers.rb', line 268

def vc_test_controller_class
  return @__vc_test_controller_class if defined?(@__vc_test_controller_class)

  defined?(ApplicationController) ? ApplicationController : ActionController::Base
end

#vc_test_request ⇒ ActionDispatch::TestRequest

Access the request used by render_inline:

test "component does not render in Firefox" do
  request.env["HTTP_USER_AGENT"] = "Mozilla/5.0"
  render_inline(NoFirefoxComponent.new)
  refute_component_rendered
end

Returns:

  • (ActionDispatch::TestRequest) 


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# File 'lib/view_component/test_helpers.rb', line 285

def vc_test_request
  require "action_controller/test_case"

  @vc_test_request ||=
    begin
      out = ActionDispatch::TestRequest.create
      out.session = ActionController::TestSession.new
      out
    end
end

#vc_test_view_context ⇒ ActionView::Base

Returns the view context used to render components in tests. Note that the view context is reset after each call to render_inline.

Returns:

  • (ActionView::Base) 


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# File 'lib/view_component/test_helpers.rb', line 52

def vc_test_view_context
  @vc_test_view_context ||= vc_test_controller.view_context
end

#with_controller_class(klass) ⇒ Object

Set the controller to be used while executing the given block, allowing access to controller-specific methods:

with_controller_class(UsersController) do
  render_inline(MyComponent.new)
end

Parameters:

  • klass (Class<ActionController::Base>) —

    The controller to be used.



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# File 'lib/view_component/test_helpers.rb', line 148

def with_controller_class(klass)
  old_controller = defined?(@vc_test_controller) && @vc_test_controller

  @vc_test_controller = __vc_test_helpers_build_controller(klass)
  yield
ensure
  @vc_test_controller = old_controller
end

#with_format(*formats) ⇒ Object

Set format of the current request

with_format(:json) do
  render_inline(MyComponent.new)
end

Parameters:

  • formats (Symbol[]) —

    The format(s) to be set for the provided block.



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# File 'lib/view_component/test_helpers.rb', line 166

def with_format(*formats)
  old_formats = vc_test_controller.view_context.lookup_context.formats

  vc_test_controller.view_context.lookup_context.formats = formats
  yield
ensure
  vc_test_controller.view_context.lookup_context.formats = old_formats
end

#with_request_url(full_path, host: nil, method: nil, protocol: nil) ⇒ Object

Set the URL of the current request (such as when using request-dependent path helpers):

with_request_url("/users/42") do
  render_inline(MyComponent.new)
end

To use a specific host, pass the host param:

with_request_url("/users/42", host: "app.example.com") do
  render_inline(MyComponent.new)
end

To specify a request method, pass the method param:

with_request_url("/users/42", method: "POST") do
  render_inline(MyComponent.new)
end

To specify a protocol, pass the protocol param:

with_request_url("/users/42", protocol: :https) do
  render_inline(MyComponent.new)
end

Parameters:

  • full_path (String) —

    The path to set for the current request.

  • host (String) (defaults to: nil) —

    The host to set for the current request.

  • method (String) (defaults to: nil) —

    The request method to set for the current request.

  • protocol (Symbol) (defaults to: nil) —

    The protocol to set for the current request (e.g., :http or :https).



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# File 'lib/view_component/test_helpers.rb', line 211

def with_request_url(full_path, host: nil, method: nil, protocol: nil)
  old_request_host = vc_test_request.host
  old_request_method = vc_test_request.request_method
  old_request_path_info = vc_test_request.path_info
  old_request_path_parameters = vc_test_request.path_parameters
  old_request_query_parameters = vc_test_request.query_parameters
  old_request_query_string = vc_test_request.query_string
  old_request_format = vc_test_request.format.symbol
  old_request_scheme = vc_test_request.scheme
  old_controller = defined?(@vc_test_controller) && @vc_test_controller

  path, query = full_path.split("?", 2)
  vc_test_request.instance_variable_set(:@fullpath, full_path)
  vc_test_request.instance_variable_set(:@original_fullpath, full_path)
  vc_test_request.host = host if host
  vc_test_request.request_method = method if method
  vc_test_request.set_header(Rack::RACK_URL_SCHEME, protocol.to_s) if protocol
  vc_test_request.path_info = path
  vc_test_request.path_parameters = Rails.application.routes.recognize_path_with_request(vc_test_request, path, {})
  vc_test_request.set_header("action_dispatch.request.query_parameters",
    Rack::Utils.parse_nested_query(query).with_indifferent_access)
  vc_test_request.set_header(Rack::QUERY_STRING, query)
  yield
ensure
  vc_test_request.host = old_request_host
  vc_test_request.request_method = old_request_method
  vc_test_request.set_header(Rack::RACK_URL_SCHEME, old_request_scheme)
  vc_test_request.path_info = old_request_path_info
  vc_test_request.path_parameters = old_request_path_parameters
  vc_test_request.set_header("action_dispatch.request.query_parameters", old_request_query_parameters)
  vc_test_request.set_header(Rack::QUERY_STRING, old_request_query_string)
  vc_test_request.format = old_request_format
  @vc_test_controller = old_controller
end

#with_variant(*variants) ⇒ Object

Set the Action Pack request variant for the given block:

with_variant(:phone) do
  render_inline(MyComponent.new)
end

Parameters:

  • variants (Symbol[]) —

    The variants to be set for the provided block.



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# File 'lib/view_component/test_helpers.rb', line 129

def with_variant(*variants)
  old_variants = vc_test_controller.view_context.lookup_context.variants

  vc_test_controller.view_context.lookup_context.variants += variants
  yield
ensure
  vc_test_controller.view_context.lookup_context.variants = old_variants
end