feat(account): Allow removal of email depending on auth method

ChangeLog.rst

@@ -11,6 +11,11 @@ Note worthy changes
 
 - Officially support Django 5.0.
 
+- In previous versions, users could never remove their primary email address.
+  This is constraint is now relaxed. In case the email address is not required,
+  for example, because the user logs in by username, removal of the email
+  address is allowed.
+
 
 Backwards incompatible changes
 ------------------------------

allauth/account/adapter.py

@@ -31,7 +31,10 @@
 
 from allauth import app_settings as allauth_app_settings
 from allauth.account import signals
-from allauth.account.app_settings import EmailVerificationMethod
+from allauth.account.app_settings import (
+    AuthenticationMethod,
+    EmailVerificationMethod,
+)
 from allauth.core import context, ratelimit
 from allauth.utils import (
     build_absolute_uri,
@@ -88,6 +91,35 @@ def is_email_verified(self, request, email):
             ret = verified_email.lower() == email.lower()
         return ret
 
+    def can_delete_email(self, email_address):
+        from allauth.account.models import EmailAddress
+
+        has_other = (
+            EmailAddress.objects.filter(user_id=email_address.user_id)
+            .exclude(pk=email_address.pk)
+            .exists()
+        )
+        login_by_email = (
+            app_settings.AUTHENTICATION_METHOD == AuthenticationMethod.EMAIL
+        )
+        if email_address.primary:
+            if has_other:
+                # Don't allow, let the user mark one of the others as primary
+                # first.
+                return False
+            elif login_by_email:
+                # Last email & login is by email, prevent dangling account.
+                return False
+            return True
+        elif has_other:
+            # Account won't be dangling.
+            return True
+        elif login_by_email:
+            # This is the last email.
+            return False
+        else:
+            return True
+
     def format_email_subject(self, subject):
         prefix = app_settings.EMAIL_SUBJECT_PREFIX
         if prefix is None:

allauth/account/tests/test_change_email.py

@@ -9,28 +9,11 @@
 import pytest
 from pytest_django.asserts import assertTemplateNotUsed, assertTemplateUsed
 
+from allauth.account.app_settings import AuthenticationMethod
 from allauth.account.models import EmailAddress, EmailConfirmationHMAC
 from allauth.account.utils import user_email
 
 
-# class ChangeEmailTests(TestCase):
-#     def setUp(self):
-#         User = get_user_model()
-#         self.user = User.objects.create(username="john", email="[email protected]")
-#         self.user.set_password("doe")
-#         self.user.save()
-#         self.email_address = EmailAddress.objects.create(
-#             user=self.user, email=self.user.email, verified=True, primary=True
-#         )
-#         self.email_address2 = EmailAddress.objects.create(
-#             user=self.user,
-#             email="[email protected]",
-#             verified=False,
-#             primary=False,
-#         )
-#         self.client.login(username="john", password="doe")
-
-
 def test_ajax_get(auth_client, user):
     primary = EmailAddress.objects.filter(user=user).first()
     secondary = EmailAddress.objects.create(
@@ -76,16 +59,8 @@ def test_ajax_add_invalid(auth_client):
     assert "valid" in data["form"]["fields"]["email"]["errors"][0]
 
 
-def test_remove_primary(auth_client, user):
-    resp = auth_client.post(
-        reverse("account_email"),
-        {"action_remove": "", "email": user.email},
-    )
-    assert EmailAddress.objects.filter(email=user.email).exists()
-    assertTemplateUsed(resp, "account/messages/cannot_delete_primary_email.txt")
-
-
-def test_ajax_remove_primary(auth_client, user):
+def test_ajax_remove_primary(auth_client, user, settings):
+    settings.ACCOUNT_AUTHENTICATION_METHOD = "email"
     resp = auth_client.post(
         reverse("account_email"),
         {"action_remove": "", "email": user.email},
@@ -320,3 +295,57 @@ def test_add_not_allowed(
         assert resp.context["form"].errors == {
             "email": ["A user is already registered with this email address."]
         }
+
+
+@pytest.mark.parametrize(
+    "authentication_method,primary_email,secondary_emails,delete_email,success",
+    [
+        (AuthenticationMethod.EMAIL, "pri@mail", ["sec@mail"], "pri@mail", False),
+        (AuthenticationMethod.EMAIL, "pri@mail", ["sec@mail"], "sec@mail", True),
+        (AuthenticationMethod.EMAIL, "pri@mail", [], "pri@mail", False),
+        (AuthenticationMethod.USERNAME, "pri@mail", ["sec@mail"], "pri@mail", False),
+        (AuthenticationMethod.USERNAME, "pri@mail", ["sec@mail"], "sec@mail", True),
+        (AuthenticationMethod.USERNAME, "pri@mail", [], "pri@mail", True),
+        (
+            AuthenticationMethod.USERNAME_EMAIL,
+            "pri@mail",
+            ["sec@mail"],
+            "pri@mail",
+            False,
+        ),
+        (
+            AuthenticationMethod.USERNAME_EMAIL,
+            "pri@mail",
+            ["sec@mail"],
+            "sec@mail",
+            True,
+        ),
+        (AuthenticationMethod.USERNAME_EMAIL, "pri@mail", [], "pri@mail", True),
+    ],
+)
+def test_remove_email(
+    client,
+    settings,
+    user_factory,
+    primary_email,
+    secondary_emails,
+    delete_email,
+    authentication_method,
+    success,
+):
+    settings.ACCOUNT_AUTHENTICATION_METHOD = authentication_method
+    user = user_factory(email=primary_email)
+    EmailAddress.objects.bulk_create(
+        [
+            EmailAddress(user=user, email=email, primary=False, verified=False)
+            for email in secondary_emails
+        ]
+    )
+    client.force_login(user)
+    resp = client.post(
+        reverse("account_email"),
+        {"action_remove": "", "email": delete_email},
+    )
+    assert EmailAddress.objects.filter(email=delete_email).exists() == (not success)
+    if not success:
+        assertTemplateUsed(resp, "account/messages/cannot_delete_primary_email.txt")

allauth/account/views.py

@@ -523,8 +523,9 @@ def _action_send(self, request, *args, **kwargs):
     def _action_remove(self, request, *args, **kwargs):
         email_address = self._get_email_address(request)
         if email_address:
-            if email_address.primary:
-                get_adapter().add_message(
+            adapter = get_adapter()
+            if not adapter.can_delete_email(email_address):
+                adapter.add_message(
                     request,
                     messages.ERROR,
                     "account/messages/cannot_delete_primary_email.txt",
@@ -538,7 +539,7 @@ def _action_remove(self, request, *args, **kwargs):
                     user=request.user,
                     email_address=email_address,
                 )
-                get_adapter().add_message(
+                adapter.add_message(
                     request,
                     messages.SUCCESS,
                     "account/messages/email_deleted.txt",