为什么 false 使 validates_presence_of 无效? [英] Why does false invalidate validates_presence_of?

问题描述

好的步骤来重现这个:

prompt> rails test_app
prompt> cd test_app
prompt> script/generate model event_service published:boolean

然后进入迁移并添加not null并默认发布为false:

then go into the migration and add not null and default published to false:

class CreateEventServices < ActiveRecord::Migration
  def self.up
    create_table :event_services do |t|
      t.boolean :published, :null => false, :default => false
      t.timestamps
    end
  end

  def self.down
    drop_table :event_services
  end
end

现在迁移您的更改并运行您的测试:

now migrate your changes and run your tests:

prompt>rake db:migrate
prompt>rake

此时您应该没有错误.现在编辑模型，以便您 validate_presence_of 已发布:

You should get no errors at this time. Now edit the model so that you validate_presence_of published:

class EventService < ActiveRecord::Base
  validates_presence_of :published
end

现在编辑单元测试event_service_test.rb:

require 'test_helper'

class EventServiceTest < ActiveSupport::TestCase
  test "the truth" do
    e = EventService.new
    e.published = false
    assert e.valid?
  end
end

并运行耙子:

prompt>rake

您将在测试中遇到错误.现在将 e.published 设置为 true 并重新运行测试.有用！我认为这可能与布尔字段有关，但我无法弄清楚.这是rails中的错误吗?还是我做错了什么?

You will get an error in the test. Now set e.published to true and rerun the test. IT WORKS! I think this probably has something to do with the field being boolean but I can't figure it out. Is this a bug in rails? or am I doing something wrong?

推荐答案

请参阅 API 文档...

如果您想验证布尔字段的存在(其中实际值为真和假)，您将需要使用 validates_inclusion_of :field_name, :in => [true, false].

If you want to validate the presence of a boolean field (where the real values are true and false), you will want to use validates_inclusion_of :field_name, :in => [true, false].

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