shoulda matchers should validate_uniqueness_of failing with scope
rspec, ruby-on-rails, shoulda
Solution
It is a known issue. It gives this error if the scoped field is dependent on the model and is also set to `:null => false`.
Also, do have a look at rails Column cannot be null:
Problem
I have 3 models, user, game, and player. There's basically a many to many relationship between users and games, with players as the join table, except players have other info so it has its own model. A player needs a unique combo of game id and user id, so I tried to say in player: ``` validates_uniqueness_of :user_id, :scope => :game_id ``` and then in my spec, I said (using shoulda matchers): ``` it { should validate_uniqueness_of(:user_id).scoped_to(:game_id)} ``` here are the relationships the player defines: ``` belongs_to :game, :inverse_of => :players belongs_to :user, :inverse_of => :players ``` yet I'm getting an ActiveRecord::statementinvalid error on that spec ``` ActiveRecord::StatementInvalid: Mysql2::Error: Column 'game_id' cannot be null: INSERT INTO `players` ETC... ``` Any idea what's going wrong?