title: Bundler: You must use Bundler 2 or greater with this lockfile
body: <p>I'm working with heroku and every time I try to push my app this message  shows out:</p>
  
  <pre><code>remote: Compressing source files... done.
  remote: Building source:
  remote: 
  remote: -----&gt; Ruby app detected
  remote: 
  remote:  !
  remote:  !     You must use Bundler 2 or greater with this lockfile.
  remote:  !
  remote: /tmp/d20181109-104-g861yi/bundler-1.15.2/gems/bundler-1.15.2/lib/bundler/lockfile_parser.rb:108:in `warn_for_outdated_bundler_version': You must use Bundler 2 or greater with this lockfile. (Bundler::LockfileError)
  remote:     from /tmp/d20181109-104-g861yi/bundler-1.15.2/gems/bundler-1.15.2/lib/bundler/lockfile_parser.rb:95:in `initialize'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:130:in `new'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:130:in `block in parse_gemfile_lock'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:18:in `block (2 levels) in instrument'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:40:in `yield_with_block_depth'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:17:in `block in instrument'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/vendor/ruby/heroku-18/lib/ruby/2.5.0/benchmark.rb:308:in `realtime'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/instrument.rb:16:in `instrument'
  remote:     from /app/tmp/buildpacks/b7af5642714be4eddaa5f35e2b4c36176b839b4abcd9bfe57ee71c358d71152b4fd2cf925c5b6e6816adee359c4f0f966b663a7f8649b0729509d510091abc07/lib/language_pack/helpers/bundler_wrapper.rb:86:in `instrument'
  remote:  !     Push rejected, failed to compile Ruby app.
  remote: 
  remote:  !     Push failed
  remote: Verifying deploy...
  remote: 
  remote: !   Push rejected to my-proyect-1234.
  remote: 
  </code></pre>
  
  <p>It says 'remote: ! You must use Bundler 2 or greater with this lockfile.'</p>
  
  <blockquote>
    <p>But my Bundler version is 2.0.0.pre.1</p>
  </blockquote>
  
  <p>Don't know what to do, I tried uninstalling bundle and installing it again, I errased the Gemfile.lock and typing <code>bundle</code> again</p>