Don’t allow unstyled links

They should always be styled with the `govuk-link` class from GOV.UK
Frontend, or another custom class.

app/main/views/api_keys.py

@@ -93,7 +93,7 @@ def create_api_key(service_id):
         disabled_options = [KEY_TYPE_NORMAL]
         option_hints[KEY_TYPE_NORMAL] = Markup(
             'Not available because your service is in '
-            '<a href="/features/trial-mode">trial mode</a>'
+            '<a class="govuk-link govuk-link--no-visited-state" href="/features/trial-mode">trial mode</a>'
         )
     if current_service.has_permission('letter'):
         option_hints[KEY_TYPE_TEAM] = 'Cannot be used to send letters'

app/main/views/invites.py

@@ -22,7 +22,8 @@ def accept_invite(token):
         message = Markup("""
             You’re signed in as {}.
             This invite is for another email address.
-            <a href={}>Sign out</a> and click the link again to accept this invite.
+            <a href={} class="govuk-link govuk-link--no-visited-state">Sign out</a>
+            and click the link again to accept this invite.
             """.format(
             current_user.email_address,
             url_for("main.sign_out", _external=True)))
@@ -78,7 +79,8 @@ def accept_org_invite(token):
         message = Markup("""
             You’re signed in as {}.
             This invite is for another email address.
-            <a href={}>Sign out</a> and click the link again to accept this invite.
+            <a class="govuk-link govuk-link--no-visited-state" href={}>Sign out</a>
+            and click the link again to accept this invite.
             """.format(
             current_user.email_address,
             url_for("main.sign_out", _external=True)))

app/templates/views/service-settings/send-files-by-email.html

@@ -21,7 +21,7 @@
         This is an API-only feature.
       </p>
       <p class="govuk-body">
-        To send a file by email, follow the instructions in our <a href={{ url_for('main.documentation') }}>API documentation</a>.
+        To send a file by email, follow the instructions in our <a class="govuk-link govuk-link--no-visited-state" href={{ url_for('main.documentation') }}>API documentation</a>.
       </p>
       <h2 class="heading-medium">{% if contact_details %}Change contact details for{% else %}Add contact details to{% endif %} the file download page</h2>
       <p class="govuk-body">

tests/app/main/views/test_accept_invite.py

@@ -453,7 +453,7 @@ def test_signed_in_existing_user_cannot_use_anothers_invite(
     assert page.h1.string.strip() == 'You’re not allowed to see this page'
     flash_banners = page.find_all('div', class_='banner-dangerous')
     assert len(flash_banners) == 1
-    banner_contents = flash_banners[0].text.strip()
+    banner_contents = normalize_spaces(flash_banners[0].text)
     assert "You’re signed in as test@user.gov.uk." in banner_contents
     assert "This invite is for another email address." in banner_contents
     assert "Sign out and click the link again to accept this invite." in banner_contents

tests/conftest.py

@@ -3030,6 +3030,7 @@ def client_request(
             if _test_for_elements_without_class and _expected_status not in (301, 302):
                 for tag, hint in (
                     ('p', 'govuk-body'),
+                    ('a', 'govuk-link govuk-link--no-visited-state'),
                 ):
                     element = page.select_one(f'{tag}:not([class])')
                     if (