RAILS 5: Bundler找不到gem“actionpack”的兼容版本：

Question

有没有人可以帮我把rails 4.2升级到rails 5.1.4在运行捆绑包更新后得到兼容版本错误

Bundler找不到gem“actionpack”的兼容版本:在Gemfile中: active_link_to (~> 1.0.0)已解析为1.0.5，这取决于actionpack

active_model_serializers (~> 0.10.6) was resolved to 0.10.7, which depends on
  actionpack (< 6, >= 4.1)

hamlit-rails (~> 0.2.0) was resolved to 0.2.0, which depends on
  actionpack (>= 4.0.1)

meta-tags (~> 2.4.1) was resolved to 2.4.1, which depends on
  actionpack (< 5.2, >= 3.2.0)

rails (~> 5.1.4) was resolved to 5.1.4, which depends on
  actionpack (= 5.1.4)

ransack (~> 1.6.6) was resolved to 1.6.6, which depends on
  actionpack (>= 3.0)

rspec-rails (~> 3.4.2) was resolved to 3.4.2, which depends on
  actionpack (< 4.3, >= 3.0)

simple_form (~> 3.5.1) was resolved to 3.5.1, which depends on
  actionpack (< 5.2, > 4)

stream_rails (>= 2.5.2, ~> 2.5) was resolved to 2.6.1, which depends on
  actionpack (>= 3.0.0)

twitter-typeahead-rails (~> 0.10.5) was resolved to 0.10.5, which depends on
  actionpack (>= 3.1)

Answer 1

您的rspec-rails阻止了升级。bundler输出显示了这一部分：

actionpack (< 4.3, >= 3.0)

所以rspec-rails会阻止任何大于4.2的值。

将rspec-rails约束~> 3.4.2释放为更宽松的内容，如~> 3.5，然后重试

bundle update rails rspec-rails

通常，在升级Rails时，可以将bundle update rails与所有对Rails有特定版本要求或在bundler中提到的Gem一起尝试。

Answer 2

删除您的Gemfile.lock并将其添加到您的Gemfile

source 'https://rubygems.org'

别忘了更新你的其他gem。

Answer 3

这发生在我试图更新到Rails6的时候。以下是我的解决方法。

source 'https://rubygems.org'
git_source(:github) { |repo| "https://github.com/#{repo}.git" }

ruby '2.6.3'


gem 'rails', '6.0.0.rc1'
gem 'sqlite3'
gem 'activerecord-jdbcsqlite3-adapter', platforms: [:jruby]
gem 'activerecord-import'
gem 'bootsnap'
gem "rspec"


group :development do
  # Access an interactive console on exception pages or by calling 'console' anywhere in the code.
  gem 'web-console', '>= 3.3.0'
  gem 'listen', '>= 3.0.5', '< 3.2'
  # Spring speeds up development by keeping your application running in the background. Read more: https://github.com/rails/spring
  gem 'spring'
  gem 'spring-watcher-listen', '~> 2.0.0'
end

platforms :rbx do
  gem 'rubysl', '~> 2.0'
  gem 'rubinius-developer_tools'
end