标签: ruby

我正在研究不同的优化技术,我发现这篇文章分析效率代码？有人认为对调用堆栈进行采样比使用分析器更有效.基本思想是,如果您查看调用堆栈,您会看到应用程序最有可能花费大部分时间的位置,然后在那里进行优化.

这当然很有趣,他显然是这方面的专家,但我不知道如何在ruby中查看调用堆栈.在调试器中,我可以说"信息堆栈",但似乎只显示一行.

编辑:我看到Mike Dunlavey的评论:"我只想指出,如果你在调试器下运行,手动中断它,并显示调用堆栈......"

我只是不确定如何手动中断它并调整调用堆栈.

我正在使用Active Admin为某些模型提供管理员.我需要为其中一个提供自定义的新表单,但将编辑表单保留为Active Admin提供的默认表单.这就是我所拥有的.它的工作原理是它给了我想要的新表单,但编辑表单也使用了新表单,这不是我想要的:

ActiveAdmin.register Document do
  form :partial => 'form'
end

我试过这个,但它给出了一个错误,'new'是一个未定义的方法:

ActiveAdmin.register Document do
  new do
    form :partial => 'form'
  end
end

在RSpec中,it_behaves_like和之间有什么区别include_examples？

该文件说:

include_examples - 包括当前背景下的示例

it_behaves_like "name" - 在嵌套上下文中包含示例

但这究竟意味着什么呢？将一个替换为另一个似乎对我的测试是通过还是失败没有影响.在某些情况下,是否有理由偏爱另一个？

另外,是it_should_behave_like和it_behaves_like刚才的同义词？

我有一个控制器"UserController",应该响应正常和ajax请求http://localhost:3000/user/3.

当它是正常请求时,我想渲染我的视图.当它是一个AJAX请求时,我想返回JSON.

正确的方法似乎是一个respond_to do |format|障碍.编写JSON很简单,但是如何让它响应HTML并像往常一样呈现视图？

  def show
    @user = User.find(params[:id])
    respond_to do |format|
      format.html {
        render :show ????this seems unnecessary. Can it be eliminated??? 
      }
      format.json { 
        render json: @user
      }
    end
  end

不确定这是否是Capybara问题,但我刚刚安装了Rails(4.1.1)和Rspec Rails(3.0.1),我想使用Capybara(2.3.0),但从未使用它我'遇到问题.我在spec/features中创建了一个"spec",规范本身按预期运行并传递,但是当运行rspec时,我得到以下"警告".有任何想法吗？我只需要在红宝石级别禁用警告吗？

/Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/mail-2.5.4/lib/mail/network/delivery_methods/sendmail.rb:53: warning: shadowing outer local variable - to
/Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:247: warning: loading in progress, circular require considered harmful - /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/capybara-2.3.0/lib/capybara.rb
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/bin/ruby_executable_hooks:15:in  `<main>'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/bin/ruby_executable_hooks:15:in  `eval'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/bin/rspec:23:in  `<main>'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/bin/rspec:23:in  `load'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/exe/rspec:4:in  `<top (required)>'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/runner.rb:38:in  `invoke'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/runner.rb:70:in  `run'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/runner.rb:85:in  `run'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/runner.rb:97:in  `setup'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/configuration.rb:1051:in  `load_spec_files'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/configuration.rb:1051:in  `each'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/configuration.rb:1051:in  `block in load_spec_files'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/rspec-core-3.0.0/lib/rspec/core/configuration.rb:1051:in  `load'
    from /Users/typeoneerror/Dev/Doki/engines/doki_core/spec/features/accounts/sign_up_spec.rb:1:in  `<top (required)>'
    from /Users/typeoneerror/Dev/Doki/engines/doki_core/spec/features/accounts/sign_up_spec.rb:1:in  `require'
    from /Users/typeoneerror/Dev/Doki/engines/doki_core/spec/rails_helper.rb:7:in  `<top (required)>'
    from /Users/typeoneerror/.rvm/gems/ruby-2.1.2@doki/gems/activesupport-4.1.1/lib/active_support/dependencies.rb:247:in …

我想用1个元素填充一个数组但是5次.到目前为止我得到了什么.

str = 1234
a = []

5.times { a << str }
puts a # => 1234, 1234, 1234, 1234, 1234

它有效,但这不是红宝石的方式.有人能指出我正确的方向来初始化一个具有5倍相同值的数组吗？

之间的差异after_create,after_save以及after_commit在Rails的是:

• after_save 在创建和更新对象时调用
• after_commit 在创建,更新和销毁时调用.
• after_create 仅在创建对象时调用

这是它们之间的唯一区别还是存在其他主要差异？

有没有办法制作一个可以接受参数的方法,但也可以在没有参数的情况下调用,在这种情况下,参数nil如下所示？

some_func(variable)

some_func

我试图安装vagrant插件vbguest,但在终端中遇到以下错误:

$ vagrant plugin install vbguest
Installing the 'vbguest' plugin. This can take a few minutes...
/usr/lib/ruby/2.3.0/rubygems/specification.rb:946:in `all=': undefined method `group_by' for nil:NilClass (NoMethodError)
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:275:in `with_isolated_gem'
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:231:in `internal_install'
    from /usr/lib/ruby/vendor_ruby/vagrant/bundler.rb:102:in `install'
    from /usr/lib/ruby/vendor_ruby/vagrant/plugin/manager.rb:62:in `block in install_plugin'
    from /usr/lib/ruby/vendor_ruby/vagrant/plugin/manager.rb:72:in `install_plugin'
    from /usr/share/vagrant/plugins/commands/plugin/action/install_gem.rb:37:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/warden.rb:34:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/builder.rb:116:in `call'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/runner.rb:66:in `block in run'
    from /usr/lib/ruby/vendor_ruby/vagrant/util/busy.rb:19:in `busy'
    from /usr/lib/ruby/vendor_ruby/vagrant/action/runner.rb:66:in `run'
    from /usr/share/vagrant/plugins/commands/plugin/command/base.rb:14:in `action'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:32:in `block in execute'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:31:in `each'
    from /usr/share/vagrant/plugins/commands/plugin/command/install.rb:31:in `execute'
    from /usr/share/vagrant/plugins/commands/plugin/command/root.rb:56:in `execute' …

我有一个 react native 项目，想为 iOS 本机细节安装可可豆荚，但安装失败，我在 Mac book pro 上安装了 ruby​​ ruby​​ 2.5.1p57

我已将错误发布下来，将不胜感激

pod install


    Analyzing dependencies
Fetching podspec for `DoubleConversion` from `../node_modules/react-native/third-party-podspecs/DoubleConversion.podspec`
Fetching podspec for `Folly` from `../node_modules/react-native/third-party-podspecs/Folly.podspec`
Fetching podspec for `GLog` from `../node_modules/react-native/third-party-podspecs/GLog.podspec`
Fetching podspec for `React` from `../node_modules/react-native`
Fetching podspec for `react-native-fetch-blob` from `../node_modules/react-native-fetch-blob`
Fetching podspec for `react-native-google-maps` from `../node_modules/react-native-maps`
Fetching podspec for `react-native-maps` from `../node_modules/react-native-maps/`
Fetching podspec for `yoga` from `../node_modules/react-native/ReactCommon/yoga`
Downloading dependencies
Using DoubleConversion (1.1.5)
Using Folly (2016.09.26.00)
Installing GLog (0.3.4)
#<Thread:0x00007fd5349ba008@/usr/local/lib/ruby/gems/2.5.0/gems/cocoapods-1.5.3/lib/cocoapods/executable.rb:166 run> terminated …