brouillon_spec: fix the slow use of have_select(locator, selected: …)

Capybara's `have_select` can be very slow for elemtns with many options
(see https://github.com/teamcapybara/capybara/issues/1527)

This is because Capybara asserts that no other elements than the
required ones are selected.

This faster version is not as complete, but helps when checking the
countries list or the years in a date picker.

spec/features/users/brouillon_spec.rb

@@ -75,11 +75,11 @@ feature 'The user' do
     expect(page).to have_field('email', with: 'loulou@yopmail.com')
     expect(page).to have_field('phone', with: '1234567890')
     expect(page).to have_checked_field('Non')
-    expect(page).to have_select('simple_drop_down_list', selected: 'val2')
-    expect(page).to have_select('multiple_drop_down_list', selected: ['val1', 'val3'])
-    expect(page).to have_select('pays', selected: 'AUSTRALIE')
-    expect(page).to have_select('regions', selected: 'region2')
-    expect(page).to have_select('departement', selected: 'dep2')
+    expect(page).to have_selected_value('simple_drop_down_list', selected: 'val2')
+    expect(page).to have_selected_value('multiple_drop_down_list', selected: ['val1', 'val3'])
+    expect(page).to have_selected_value('pays', selected: 'AUSTRALIE')
+    expect(page).to have_selected_value('regions', selected: 'region2')
+    expect(page).to have_selected_value('departement', selected: 'dep2')
     expect(page).to have_checked_field('engagement')
     expect(page).to have_field('dossier_link', with: '123')
     expect(page).to have_text('file.pdf')
@@ -229,10 +229,10 @@ feature 'The user' do
   end
 
   def check_date_and_time(date, field)
-    expect(page).to have_select("#{field}_1i", selected: date.strftime('%Y'))
-    expect(page).to have_select("#{field}_2i", selected: I18n.l(date, format: '%B'))
-    expect(page).to have_select("#{field}_3i", selected: date.strftime('%-d'))
-    expect(page).to have_select("#{field}_4i", selected: date.strftime('%H'))
-    expect(page).to have_select("#{field}_5i", selected: date.strftime('%M'))
+    expect(page).to have_selected_value("#{field}_1i", selected: date.strftime('%Y'))
+    expect(page).to have_selected_value("#{field}_2i", selected: I18n.l(date, format: '%B'))
+    expect(page).to have_selected_value("#{field}_3i", selected: date.strftime('%-d'))
+    expect(page).to have_selected_value("#{field}_4i", selected: date.strftime('%H'))
+    expect(page).to have_selected_value("#{field}_5i", selected: date.strftime('%M'))
   end
 end

spec/spec_helper.rb

@@ -167,4 +167,22 @@ RSpec.configure do |config|
       actual.attributes.with_indifferent_access.except(*ignored) == expected.attributes.with_indifferent_access.except(*ignored)
     end
   end
+
+  # Asserts that a given select element exists in the page,
+  # and that the option(s) with the given value(s) are selected.
+  #
+  # Usage: expect(page).to have_selected_value('Country', selected: 'Australia')
+  #
+  # For large lists, this is much faster than `have_select(location, selected: value)`,
+  # as it doesn’t check that every other options are not selected.
+  RSpec::Matchers.define(:have_selected_value) do |select_locator, options|
+    match do |page|
+      values = options[:selected].is_a?(String) ? [options[:selected]] : options[:selected]
+
+      select_element = page.first(:select, select_locator)
+      select_element && values.all? do |value|
+        select_element.first(:option, value).selected?
+      end
+    end
+  end
 end