test "GETtting correct activation link on an already activated user gives error message and redirects to root url" do
    # GIVEN a non-yet-registered email address
    email_address = "tester@testing.net"
    # GIVEN the sign-up page has been displayd
    get signup_path
    # GIVEN new user is created
    post signup_path, params: { user: { email: email_address, email_confirmation: email_address, password: "testpassword", password_confirmation: "testpassword" } }
    # GIVEN the URI from activation email
    activation_uri = URI.extract(ActionMailer::Base.deliveries.last.text_part.body.encoded)[0]
    # GIVEN the URI's been used and the user is already activated
    get activation_uri
    # WHEN reading back the newly activated user
    activated_user = User.find_by_email(email_address)
    # EXPECT the user to be activated
    assert activated_user.activated?
    # WHEN using the activation link on an already activated user
    get activation_uri
    # EXPECT redirection to root path
    assert_redirected_to root_url
    follow_redirect!
    # EXPECT flash message
    assert_not flash.empty?
    # EXPECT rendered page to contain activation error information
    assert_select 'div#flash div h5', text: I18n.translate('users.activate.error')
end

test "GETtting incorrect activation hash on a non-activated user gives error message and redirects to root url" do
    # GIVEN a non-yet-registered email address
    email_address = "tester@testing.net"
    # GIVEN the sign-up page has been displayd
    get signup_path
    # GIVEN new user is created
    post signup_path, params: { user: { email: email_address, email_confirmation: email_address, password: "testpassword", password_confirmation: "testpassword" } }
    # WEHN GETting the activation URI with invalid activation hash
    activation_uri = "http://localhost:3000/account_activations/waTbfcCoZoPTBEIcewsl8Q/edit?email=#{ERB::Util.url_encode(email_address)}"
    get activation_uri
    # EXPECT redirection to root path
    assert_redirected_to root_url
    follow_redirect!
    # EXPECT flash message
    assert_not flash.empty?
    # EXPECT flash message to contain activation error information
    assert_equal I18n.translate('users.activate.error'), flash[:error]
    # EXPECT rendered page to contain activation error information ('You are being redirected' rendered here)
    assert_select 'div#flash div h5', text: I18n.translate('users.activate.error')
end

flash[:error] = "#{t'users.activate.error'}"
redirect_to root_url