Add JS-enabled integration tests for /users page

The equivalent non-JS functionality is already being tested in
controller and unit tests. These additional happy path tests should give
us confidence that the JavaScript functionality continues to work as
expected.

test/integration/admin_user_index_test.rb

@@ -3,6 +3,8 @@
 class AdminUserIndexTest < ActionDispatch::IntegrationTest
   context "logged in as an admin" do
     setup do
+      use_javascript_driver
+
       current_time = Time.zone.now
       Timecop.freeze(current_time)
 
@@ -13,27 +15,92 @@ class AdminUserIndexTest < ActionDispatch::IntegrationTest
       org1 = create(:organisation, name: "Org 1")
       org2 = create(:organisation, name: "Org 2")
 
-      create(:user, name: "Aardvark", email: "aardvark@example.com", current_sign_in_at: current_time - 5.minutes)
-      create(:two_step_enabled_user, name: "Abbey", email: "abbey@example.com")
-      create(:user, name: "Abbot", email: "mr_ab@example.com")
-      create(:user, name: "Bert", email: "bbbert@example.com")
-      create(:user, name: "Ed", email: "ed@example.com", organisation: org1)
-      create(:user, name: "Eddie", email: "eddie_bb@example.com")
-      create(:two_step_exempted_user, name: "Ernie", email: "ernie@example.com", organisation: org2)
-      create(:suspended_user, name: "Suspended McFee", email: "suspenders@example.com")
+      @aardvark = create(:user, name: "Aardvark", email: "aardvark@example.com", current_sign_in_at: current_time - 5.minutes)
+      @abbey = create(:two_step_enabled_user, name: "Abbey", email: "abbey@example.com")
+      @abbot = create(:user, name: "Abbot", email: "mr_ab@example.com")
+      @bert = create(:user, name: "Bert", email: "bbbert@example.com")
+      @ed = create(:user, name: "Ed", email: "ed@example.com", organisation: org1)
+      @eddie = create(:user, name: "Eddie", email: "eddie_bb@example.com")
+      @ernie = create(:two_step_exempted_user, name: "Ernie", email: "ernie@example.com", organisation: org2)
+      @suspended_mcfee = create(:suspended_user, name: "Suspended McFee", email: "suspenders@example.com")
+
+      application = create(:application, name: "App name")
+      create(:supported_permission, application:, name: "App permission")
+      @aardvark.grant_application_signin_permission(application)
+      @bert.grant_application_permission(application, "App permission")
+
+      visit "/users"
     end
 
     teardown do
       Timecop.return
     end
 
     should "display the 2SV enrollment status for users" do
-      visit "/users"
-
       within "table" do
         assert has_css?("td", text: "Enabled", count: 1)
         assert has_css?("td", text: "Not set up", count: 7)
       end
     end
+
+    should "list all users" do
+      assert_results @admin, @aardvark, @abbey, @abbot, @bert, @ed, @eddie, @ernie, @suspended_mcfee
+    end
+
+    should "filter users by status" do
+      check "Suspended", allow_label_click: true
+
+      assert_results @suspended_mcfee
+    end
+
+    should "filter users by 2sv status" do
+      click_on "2SV Status"
+
+      check "Exempted", allow_label_click: true
+      assert_results @ernie
+
+      check "Enable", allow_label_click: true
+      assert_results @ernie, @abbey
+    end
+
+    should "filter users by role" do
+      click_on "Role"
+
+      check "Admin", allow_label_click: true
+      assert_results @admin
+    end
+
+    should "filter users by organisation" do
+      click_on "Organisation"
+
+      check "Org 1", allow_label_click: true
+      assert_results @ed
+
+      check "Org 2", allow_label_click: true
+      assert_results @ed, @ernie
+    end
+
+    should "filter users by permission" do
+      click_on "Permissions"
+
+      check "App name signin", allow_label_click: true
+      assert_results @aardvark
+
+      check "App name App permission", allow_label_click: true
+      assert_results @aardvark, @bert
+    end
+  end
+
+private
+
+  def assert_results(*users)
+    expected_table_caption = [users.count, "user".pluralize(users.count)].join(" ")
+
+    table = find("table caption", text: expected_table_caption).ancestor(:table)
+    assert table.has_css?("tbody tr", count: users.count)
+
+    users.each do |user|
+      assert table.has_content?(user.name)
+    end
   end
 end