Reproduction for https://github.com/rails/rails/issues/5982

5982.rb

require 'bundler'
Bundler.setup(:default)

require 'active_record'
require 'minitest/autorun'
require 'logger'

# This connection will do for database-independent bug reports.
ActiveRecord::Base.establish_connection(adapter: 'sqlite3', database: ':memory:')
ActiveRecord::Base.logger = Logger.new(STDOUT)

ActiveRecord::Schema.define do
  create_table "Manufacturers", primary_key: 'manufacturer_id' do |t|
    t.string :manufacturer_name
  end

  execute "INSERT INTO Manufacturers(manufacturer_name) values('Ford')"
  execute "INSERT INTO Manufacturers(manufacturer_name) values('GM')"
  execute "INSERT INTO Manufacturers(manufacturer_name) values('Chrysler')"

  execute "CREATE VIEW v_manufacturers AS SELECT manufacturer_id, manufacturer_name as name FROM Manufacturers"

  create_table :cars do |t|
    t.string :name
    t.references :manufacturer

    t.timestamps
  end
  add_index :cars, :manufacturer_id
end

class Manufacturer < ActiveRecord::Base
  self.table_name = 'v_manufacturers'
  self.primary_key = 'id'
end

class Car < ActiveRecord::Base
  belongs_to :manufacturer
end

class BugTest < Minitest::Test
  def test_association_stuff
    assert Manufacturer.new(name: 'Toyota').id.nil?
  end
end