ostatus: explicitly disallow protocol downgrade from activitypub

This closes embargoed bug #1135.

test/web/ostatus/ostatus_test.exs

@@ -426,7 +426,7 @@ defmodule Pleroma.Web.OStatusTest do
                }
     end
 
-    test "find_make_or_update_user takes an author element and returns an updated user" do
+    test "find_make_or_update_actor takes an author element and returns an updated user" do
       uri = "https://social.heldscal.la/user/23211"
 
       {:ok, user} = OStatus.find_or_make_user(uri)
@@ -439,14 +439,56 @@ defmodule Pleroma.Web.OStatusTest do
 
       doc = XML.parse_document(File.read!("test/fixtures/23211.atom"))
       [author] = :xmerl_xpath.string('//author[1]', doc)
-      {:ok, user} = OStatus.find_make_or_update_user(author)
+      {:ok, user} = OStatus.find_make_or_update_actor(author)
       assert user.avatar["type"] == "Image"
       assert user.name == old_name
       assert user.bio == old_bio
 
-      {:ok, user_again} = OStatus.find_make_or_update_user(author)
+      {:ok, user_again} = OStatus.find_make_or_update_actor(author)
       assert user_again == user
     end
+
+    test "find_or_make_user disallows protocol downgrade" do
+      user = insert(:user, %{local: true})
+      {:ok, user} = OStatus.find_or_make_user(user.ap_id)
+
+      assert User.ap_enabled?(user)
+
+      user =
+        insert(:user, %{
+          ap_id: "https://social.heldscal.la/user/23211",
+          info: %{ap_enabled: true},
+          local: false
+        })
+
+      assert User.ap_enabled?(user)
+
+      {:ok, user} = OStatus.find_or_make_user(user.ap_id)
+      assert User.ap_enabled?(user)
+    end
+
+    test "find_make_or_update_actor disallows protocol downgrade" do
+      user = insert(:user, %{local: true})
+      {:ok, user} = OStatus.find_or_make_user(user.ap_id)
+
+      assert User.ap_enabled?(user)
+
+      user =
+        insert(:user, %{
+          ap_id: "https://social.heldscal.la/user/23211",
+          info: %{ap_enabled: true},
+          local: false
+        })
+
+      assert User.ap_enabled?(user)
+
+      {:ok, user} = OStatus.find_or_make_user(user.ap_id)
+      assert User.ap_enabled?(user)
+
+      doc = XML.parse_document(File.read!("test/fixtures/23211.atom"))
+      [author] = :xmerl_xpath.string('//author[1]', doc)
+      {:error, :invalid_protocol} = OStatus.find_make_or_update_actor(author)
+    end
   end
 
   describe "gathering user info from a user id" do