[ruby-cvs:78926] 75dca097b8 (master): [bundler/bundler] Do `require "rubygems"` only when needed

Yusuke Endoh	2019-12-25 14:13:15 +0900 (Wed, 25 Dec 2019)

  New Revision: 75dca097b8

  https://github.com/ruby/ruby/commit/75dca097b8

  Log:
    [bundler/bundler] Do `require "rubygems"` only when needed
    
    This require causes circular require.
    
    ```
    $ touch empty_file
    
    $ RUBYGEMS_GEMDEPS=empty_file ./local/bin/ruby -w -e ''
    /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92: warning: /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92: warning: loading in progress, circular require considered harmful - /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb
    from <internal:gem_prelude>:1:in  `<internal:gem_prelude>'
    from <internal:gem_prelude>:1:in  `require'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1417:in  `<top (required)>'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1203:in  `use_gemdeps'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/user_interaction.rb:47:in  `use_ui'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems.rb:1204:in  `block in use_gemdeps'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in  `require'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in  `require'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler.rb:11:in  `<top (required)>'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler.rb:11:in  `require_relative'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/bundler/rubygems_integration.rb:3:in  `<top (required)>'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in  `require'
    from /home/mame/work/ruby/local/lib/ruby/2.7.0/rubygems/core_ext/kernel_require.rb:92:in  `require'
    ```
    
    https://github.com/bundler/bundler/commit/c7c5bcea92

  Modified files:
    lib/bundler/rubygems_integration.rb