Methods
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P
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Instance Public methods
assert_template(options = {}, message = nil)

Asserts that the request was rendered with the appropriate template file or partials.

Examples

# assert that the "new" view template was rendered
assert_template "new"

# assert that the layout 'admin' was rendered
assert_template :layout => 'admin'
assert_template :layout => 'layouts/admin'
assert_template :layout => :admin

# assert that no layout was rendered
assert_template :layout => nil
assert_template :layout => false

# assert that the "_customer" partial was rendered twice
assert_template :partial => '_customer', :count => 2

# assert that no partials were rendered
assert_template :partial => false

In a view test case, you can also assert that specific locals are passed to partials:

# assert that the "_customer" partial was rendered with a specific object
assert_template :partial => '_customer', :locals => { :customer => @customer }

Source: show | on GitHub 

# File actionpack/lib/action_controller/test_case.rb, line 85
def assert_template(options = {}, message = nil)
  validate_request!
  # Force body to be read in case the template is being streamed
  response.body

  case options
  when NilClass, String, Symbol
    options = options.to_s if Symbol === options
    rendered = @templates
    msg = build_message(message,
            "expecting <?> but rendering with <?>",
            options, rendered.keys.join(', '))
    assert_block(msg) do
      if options
        rendered.any? { |t,num| t.match(options) }
      else
        @templates.blank?
      end
    end
  when Hash
    if options.key?(:layout)
      expected_layout = options[:layout]
      msg = build_message(message,
              "expecting layout <?> but action rendered <?>",
              expected_layout, @layouts.keys)

      case expected_layout
      when String, Symbol
        assert(@layouts.keys.include?(expected_layout.to_s), msg)
      when Regexp
        assert(@layouts.keys.any? {|l| l =~ expected_layout }, msg)
      when nil, false
        assert(@layouts.empty?, msg)
      end
    end

    if expected_partial = options[:partial]
      if expected_locals = options[:locals]
        if defined?(@locals)
          actual_locals = @locals[expected_partial.to_s.sub(/^_/,'')]
          expected_locals.each_pair do |k,v|
            assert_equal(v, actual_locals[k])
          end
        else
          warn "the :locals option to #assert_template is only supported in a ActionView::TestCase"
        end
      elsif expected_count = options[:count]
        actual_count = @partials[expected_partial]
        msg = build_message(message,
                "expecting ? to be rendered ? time(s) but rendered ? time(s)",
                 expected_partial, expected_count, actual_count)
        assert(actual_count == expected_count.to_i, msg)
      else
        msg = build_message(message,
                "expecting partial <?> but action rendered <?>",
                options[:partial], @partials.keys)
        assert(@partials.include?(expected_partial), msg)
      end
    elsif options.key?(:partial)
      assert @partials.empty?,
        "Expected no partials to be rendered"
    end
  end
end
process(*args)

Source: show | on GitHub 

# File actionpack/lib/action_controller/test_case.rb, line 50
def process(*args)
  @partials = Hash.new(0)
  @templates = Hash.new(0)
  @layouts = Hash.new(0)
  super
end
setup_subscriptions()

Source: show | on GitHub 

# File actionpack/lib/action_controller/test_case.rb, line 16
def setup_subscriptions
  @partials = Hash.new(0)
  @templates = Hash.new(0)
  @layouts = Hash.new(0)

  ActiveSupport::Notifications.subscribe("render_template.action_view") do |name, start, finish, id, payload|
    path = payload[:layout]
    if path
      @layouts[path] += 1
      if path =~ /^layouts\/(.*)/
        @layouts[$1] += 1
      end
    end
  end

  ActiveSupport::Notifications.subscribe("!render_template.action_view") do |name, start, finish, id, payload|
    path = payload[:virtual_path]
    next unless path
    partial = path =~ /^.*\/_[^\/]*$/
    if partial
      @partials[path] += 1
      @partials[path.split("/").last] += 1
      @templates[path] += 1
    else
      @templates[path] += 1
    end
  end
end
teardown_subscriptions()

Source: show | on GitHub 

# File actionpack/lib/action_controller/test_case.rb, line 45
def teardown_subscriptions
  ActiveSupport::Notifications.unsubscribe("render_template.action_view")
  ActiveSupport::Notifications.unsubscribe("!render_template.action_view")
end