Make sure the path is correctly escaped in case it contains spaces.

[andrewmarkle]

Closes #1044. This fixes an issue where the test runner fails if you have spaces in your path.

This PR uses Regexp to escape the path before the command is run.

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This change is 

[justin808]

Why is this the right solution for shell escaping?

[justin808]

What if put quotes around the value:

"cd \"#{ReactOnRails.configuration.node_modules_location}\" && #{cmd}"

[andrewmarkle]

Good idea! Didn't think of that. I like that solution better!

[justin808]

Travis failure:

Offenses:
lib/react_on_rails/utils.rb:149:19: C: Style/ColonMethodCall: Do not use :: for method calls.
      "cd #{Regexp::escape(ReactOnRails.configuration.node_modules_location.to_s)} && #{cmd}"
                  ^^
139 files inspected, 1 offense detected
rake aborted!

[justin808]

@andrewmarkle we have this CI failure:

Failures:
  1) ReactOnRails::TestHelper::WebpackAssetsCompiler#ensureAssetsCompiled when assets compiler command is invalid prints the correct message
     Failure/Error:
       expect do
         begin
           ReactOnRails::TestHelper::WebpackAssetsCompiler.new.compile_assets
           # rubocop:disable Lint/HandleExceptions
         rescue SystemExit
           # No op
         end
         # rubocop:enable Lint/HandleExceptions
       end.to output(/#{expected_output}/).to_stdout
     
       expected block to output /React on Rails FATAL ERROR!
       Error in building webpack assets!
       cmd: cd  && sh -c 'exit 1'
       / to stdout, but output "\nBuilding Webpack assets...\n\e[31m================================================================...tatus: 1\n================================================================================\n\e[0m\n"
       Diff:
       
       @@ -1,5 +1,10 @@
       -/React on Rails FATAL ERROR!
       +
       +Building Webpack assets...
       +================================================================================
       +React on Rails FATAL ERROR!
        Error in building webpack assets!
       -cmd: cd  && sh -c 'exit 1'
       -/
       +cmd: cd "" && sh -c 'exit 1'
       +exitstatus: 1
       +================================================================================
       +
       
     # ./spec/react_on_rails/test_helper/webpack_assets_compiler_spec.rb:30:in `block (4 levels) in <top (required)>'
     # /home/travis/.rvm/gems/ruby-2.5.0/gems/rspec-retry-0.5.5/lib/rspec/retry.rb:115:in `block in run'
     # /home/travis/.rvm/gems/ruby-2.5.0/gems/rspec-retry-0.5.5/lib/rspec/retry.rb:104:in `loop'
     # /home/travis/.rvm/gems/ruby-2.5.0/gems/rspec-retry-0.5.5/lib/rspec/retry.rb:104:in `run'
     # /home/travis/.rvm/gems/ruby-2.5.0/gems/rspec-retry-0.5.5/lib/rspec_ext/rspec_ext.rb:12:in `run_with_retry'
     # /home/travis/.rvm/gems/ruby-2.5.0/gems/rspec-retry-0.5.5/lib/rspec/retry.rb:33:in `block (2 levels) in setup'
Finished in 1 minute 18.36 seconds (files took 1.29 seconds to load)
144 examples, 1 failure
Failed examples:
rspec ./spec/react_on_rails/test_helper/webpack_assets_compiler_spec.rb:23 # ReactOnRails::TestHelper::WebpackAssetsCompiler#ensureAssetsCompiled when assets compiler command is invalid prints the correct message

[coveralls]

Coverage remained the same at ?% when pulling 144ecba on andrewmarkle:escape-path-fix into a6fc8d8 on shakacode:master.

[coveralls]

Coverage remained the same at ?% when pulling 455b33e on andrewmarkle:escape-path-fix into 6b3641a on shakacode:master.

[andrewmarkle]

Thanks @justin808 for your patience! Should be good to go now.

[justin808]

Reviewed 1 of 1 files at r2, 1 of 1 files at r3.
Review status: all files reviewed at latest revision, 2 unresolved discussions, some commit checks failed.

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spec/react_on_rails/test_helper/webpack_assets_compiler_spec.rb, line 27 at r3 (raw file):

          React on Rails FATAL ERROR!
          Error in building webpack assets!
          cmd: cd \"#{Rails.root}\" && #{invalid_command}

If this is in a heredoc, why do you escape the "? @andrewmarkle

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Comments from Reviewable

[justin808]

Please add a changelog entry

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Review status: all files reviewed at latest revision, 2 unresolved discussions, some commit checks failed.

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Comments from Reviewable

[justin808]

@andrewmarkle ?

[andrewmarkle]

If this is in a heredoc, why do you escape the "?

I couldn't get this to work otherwise. If you just add in the escape characters, the heredoc ignores the interpolation and it outputs #{Rails.root} as part of the string.

Do you have another suggestion?

[justin808]

LGTM

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Reviewed 1 of 1 files at r4.
Review status: all files reviewed at latest revision, 1 unresolved discussion.

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Comments from Reviewable