title: How do I debug why a gem install fails?
body: <p>I'm trying to install <a href="https://github.com/tallakt/geoutm" rel="noreferrer">geoutm</a> using <code>gem install geoutm</code>. The Github repository doesn't have an issues page, so I'm trying to fix the issue myself then submit a pull request. This is the issue:</p>
  
  <pre>$ gem install geoutm
  Fetching: geoutm-1.0.1.gem (100%)
  Successfully installed geoutm-1.0.1
  ERROR:  While executing gem ... (TypeError)
      no implicit conversion of Array into String</pre>
  
  <p>It says "successfully installed", but trying to require the gem fails. Verbose install isn't much more useful:</p>
  
  <pre>$ gem install geoutm --verbose
  HEAD https://rubygems.org/latest_specs.4.8.gz
  302 Moved Temporarily
  HEAD https://s3.amazonaws.com/production.s3.rubygems.org/latest_specs.4.8.gz
  200 OK
  GET https://rubygems.org/latest_specs.4.8.gz
  302 Moved Temporarily
  GET https://s3.amazonaws.com/production.s3.rubygems.org/latest_specs.4.8.gz
  200 OK
  Installing gem geoutm-1.0.1
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/latlon_spec.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/geoutm_spec.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/spec_helper.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/utm_spec.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/testdata.yaml
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/spec.opts
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/spec/ellipsoid_spec.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm/utm_zones.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm/geo_utm_exception.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm/utm.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm/ellipsoid.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm/latlon.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/lib/geoutm.rb
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/LICENCE
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/README.rdoc
  /home/tomas/.rvm/gems/ruby-2.0.0-p247/gems/geoutm-1.0.1/History.txt
  Successfully installed geoutm-1.0.1
  ERROR:  While executing gem ... (TypeError)
      no implicit conversion of Array into String</pre>
  
  <p>The gem works flawlessly when downloaded manually and used without installation.</p>
  
  <p>The issue is that I don't know how to figure out where the type error occurs. I can't find any install logs or more verbose output flags. Any idea how I can figure out this error?</p>