为什么Cocoapods找不到我的source_files模式？

Question

Cocoapods报道

The `source_files` pattern did not match any file.

为什么它不匹配我目录中的文件？

NHVersionHelper.podspec

Pod::Spec.new do |s|
  s.name         = "NHVersionHelper"
  s.version      = "1.0.0"
  s.summary      = "iOS 检测版本升级工具"
  s.description  = <<-DESC
  iOS 从app store检测版本升级工具
                   DESC
  s.homepage     = "https://github.com/neghao/NHVersionHelper"
  s.license      = { :type => "MIT", :file => "LICENSE" }
  s.author       = { "neghao" => "neghao@162.com" }
  s.platform     = :ios, "7.0"
  s.source       = { :git => "https://github.com/neghao/NHVersionHelper.git", 
                     :tag => "#{s.version}" }
  s.source_files  = "NHVersionHelper/*.{h,m}"
  end



  error info:

   Testing with xcodebuild. 
 -> NHVersionHelper (1.0.0)
    - ERROR | [iOS] file patterns: The `source_files` pattern did not match any file.

Analyzed 1 podspec.

[!] The spec did not pass validation, due to 1 error.

＆＃34; NHVersionHelper＆＃34;这个文件夹和＆＃34; NHVersionHelper.podspec＆＃34;在同一目录中