1 files changed, 11 insertions, 0 deletions
diff --git a/app/models/namespace.rb b/app/models/namespace.rb
index 901dbf2ba69..0ff169d4531 100644
--- a/app/models/namespace.rb
+++ b/app/models/namespace.rb
@@ -40,6 +40,7 @@ class Namespace < ActiveRecord::Base
     namespace_path: true
 
   validate :nesting_level_allowed
+  validate :allowed_path_by_redirects
 
   delegate :name, to: :owner, allow_nil: true, prefix: true
 
@@ -257,4 +258,14 @@ class Namespace < ActiveRecord::Base
     Namespace.where(id: descendants.select(:id))
       .update_all(share_with_group_lock: true)
   end
+
+  def allowed_path_by_redirects
+    return if path.nil?
+
+    errors.add(:path, "#{path} has been taken before. Please use another one") if namespace_previously_created_with_same_path?
+  end
+
+  def namespace_previously_created_with_same_path?
+    RedirectRoute.permanent.exists?(path: path)
+  end
 end