Rails 3 模板:奇怪的inject_into_file

Question

我正在为 Rails 3 编写一个模板（你可以在这里找到它），我在以下几行方面遇到了麻烦：

# 8. config/database.yml modifications
if yes?("Do you want to set the database host to '/var/run/postgresql'?")
  inject_into_file "config/database.yml", " host: /var/run/postgresqln", :after => "development:n"

  # FIXME these two won't work :(((( why????
  # inject_into_file "config/database.yml", " host: /var/run/postgresqln", :after => "production:n"
  # inject_into_file "config/database.yml", " host: /var/run/postgresqln", :after => "test:n"

  # Not finding other solutions, I rewrite the two blocks above with two seds
  run %q(sed -i '/test:/a  host: /var/run/postgresql' config/database.yml)
  run %q(sed -i '/production:/a  host: /var/run/postgresql' config/database.yml)
end

也就是说，第一个inject_to_file工作，并且在config/database.yml中我有

development:
  host: /var/run/postgresql

但是其他两个inject_to_file已成功应用，但不要修改 config/database.yml！所以我有

test:
  adapter: postgresql

和

production:
  adapter: postgresql

Answer 1

您必须指定 :force => true 选项才能多次注入相同的文本。看：

http://rdoc.info/github/wycats/thor/master/Thor/Actions#insert_into_file-instance_method

这个版本对我有用：

https://gist.github.com/2573325

不要问我为什么这个选项有任何意义，呵呵。

Answer 2

我在这里跌跌撞撞地寻找一个稍微不同的问题的解决方案：

rails 文档说以这种方式使用inject_into_file

inject_into_file 'name_of_file.rb', after: "#The code goes below this line. Don't forget the Line break at the endn" do <<-'RUBY'
  puts "Hello World"
RUBY
end

但是，这并不总是对我有用。在某些情况下，它实际上会将单词"puts"和一些 ruby 代码输出到我尝试注入的文件中。

最后我发现你可以传递一个字符串inject_into_file这要容易得多。

inject_into_file 'name_of_file.rb', :after => "#The code goes below this line. Don't forget the Line break at the endn" do
  "Hello World"
end