如何在项目中更新Rails的版本?捆绑程序找不到gem“activemodel”的兼容版本

activemodel >=4.2.0,>=4.0,且=5.2.1.rc1。那么为什么它不选择5.2.1.rc1,因为它满足所有依赖关系?

宝石有几十个这样的错误 rails , railties

我正在从Rails 4.2升级到最新的Rails。我注释掉了除了Ruby和Rails之外的所有版本说明符。这是我的全部 Gemfile

workspace\>bundle
Fetching gem metadata from https://rubygems.org/..............
Fetching gem metadata from https://rubygems.org/..
You have requested:
  rails ~> 5.2

The bundle currently has rails locked at 4.2.3.
Try running `bundle update rails`

If you are updating multiple gems in your Gemfile at once,
try passing them all to `bundle update`

C:\Users\Chloe\workspace\>bundle update rails
Fetching gem metadata from https://rubygems.org/..............
Fetching gem metadata from https://rubygems.org/..
Resolving dependencies........
Bundler could not find compatible versions for gem "activemodel":
  In Gemfile:
    paperclip (~> 5.0) x64-mingw32 was resolved to 5.0.0, which depends on
      activemodel (>= 4.2.0) x64-mingw32

    rails (~> 5.2) x64-mingw32 was resolved to 5.2.1.rc1, which depends on
      activemodel (= 5.2.1.rc1) x64-mingw32

    web-console (~> 2.0) x64-mingw32 was resolved to 2.3.0, which depends on
      activemodel (>= 4.0) x64-mingw32