Fix crash when a remote Flag activity mentions a private post (#18760)

* Add tests

* Fix crash when a remote Flag activity mentions a private post

1 files changed, 10 insertions, 1 deletions

diff --git a/app/services/report_service.rb b/app/services/report_service.rb
index 70212a6a7..bd67ff8d3 100644
--- a/app/services/report_service.rb
+++ b/app/services/report_service.rb
@@ -57,7 +57,16 @@ class ReportService < BaseService
   end
 
   def reported_status_ids
-    AccountStatusesFilter.new(@target_account, @source_account).results.with_discarded.find(Array(@status_ids)).pluck(:id)
+    return AccountStatusesFilter.new(@target_account, @source_account).results.with_discarded.find(Array(@status_ids)).pluck(:id) if @source_account.local?
+
+    # If the account making reports is remote, it is likely anonymized so we have to relax the requirements for attaching statuses.
+    domain = @source_account.domain.to_s.downcase
+    has_followers = @target_account.followers.where(Account.arel_table[:domain].lower.eq(domain)).exists?
+    visibility = has_followers ? %i(public unlisted private) : %i(public unlisted)
+    scope = @target_account.statuses.with_discarded
+    scope.merge!(scope.where(visibility: visibility).or(scope.where('EXISTS (SELECT 1 FROM mentions m JOIN accounts a ON m.account_id = a.id WHERE lower(a.domain) = ?)', domain)))
+    # Allow missing posts to not drop reports that include e.g. a deleted post
+    scope.where(id: Array(@status_ids)).pluck(:id)
   end
 
   def payload