BUNDLE-EXEC(1)							BUNDLE-EXEC(1)



1mNAME0m
       1mbundle-exec 22m- Execute a command in the context of the bundle

1mSYNOPSIS0m
       1mbundle exec 22m[--keep-file-descriptors] 4mcommand0m

1mDESCRIPTION0m
       This  command  executes	the  command, making all gems specified in the
       1mGemfile(5) 22mavailable to 1mrequire 22min Ruby programs.

       Essentially, if you  would  normally  have  run	something  like  1mrspec0m
       1mspec/my_spec.rb22m,  and  you	want  to use the gems specified in the 1mGem-0m
       1mfile(5) 22mand installed via bundle install(1) 4mbundle-install.1.html24m,  you
       should run 1mbundle exec rspec spec/my_spec.rb22m.

       Note  that 1mbundle exec 22mdoes not require that an executable is available
       on your shell's 1m$PATH22m.

1mOPTIONS0m
       1m--keep-file-descriptors0m
	      Exec in Ruby 2.0 began discarding non-standard file descriptors.
	      When  this flag is passed, exec will revert to the 1.9 behaviour
	      of passing all file descriptors to the new process.

1mBUNDLE INSTALL --BINSTUBS0m
       If  you	use  the   1m--binstubs   22mflag   in	 bundle   install(1)   4mbun-0m
       4mdle-install.1.html24m,  Bundler  will	automatically  create  a  directory
       (which defaults to 1mapp_root/bin22m)  containing  all  of  the	executables
       available from gems in the bundle.

       After  using 1m--binstubs22m, 1mbin/rspec spec/my_spec.rb 22mis identical to 1mbun-0m
       1mdle exec rspec spec/my_spec.rb22m.

1mENVIRONMENT MODIFICATIONS0m
       1mbundle exec 22mmakes a number of changes to the  shell  environment,  then
       executes the command you specify in full.

       o   make  sure  that  it's  still  possible to shell out to 1mbundle 22mfrom
	   inside a command invoked by 1mbundle exec 22m(using 1m$BUNDLE_BIN_PATH22m)

       o   put	the  directory	containing  executables  (like	1mrails22m,  1mrspec22m,
	   1mrackup22m) for your bundle on 1m$PATH0m

       o   make  sure  that if bundler is invoked in the subshell, it uses the
	   same 1mGemfile 22m(by setting 1mBUNDLE_GEMFILE22m)

       o   add 1m-rbundler/setup 22mto 1m$RUBYOPT22m, which makes sure	that  Ruby  pro-
	   grams invoked in the subshell can see the gems in the bundle



       It also modifies Rubygems:

       o   disallow loading additional gems not in the bundle

       o   modify  the 1mgem 22mmethod to be a no-op if a gem matching the require-
	   ments is in the bundle, and to raise a 1mGem::LoadError 22mif it's not

       o   Define 1mGem.refresh 22mto be a no-op, since the source index is  always
	   frozen  when  using	bundler,  and  to prevent gems from the system
	   leaking into the environment

       o   Override 1mGem.bin_path 22mto use the gems in the bundle, making  system
	   executables work

       o   Add all gems in the bundle into Gem.loaded_specs



   1mLoading0m
       By  default,  when attempting to 1mbundle exec 22mto a file with a ruby she-
       bang, Bundler will 1mKernel.load 22mthat file instead of using  1mKernel.exec22m.
       For the vast majority of cases, this is a performance improvement. In a
       rare few cases, this could cause  some  subtle  side-effects  (such  as
       dependence  on  the exact contents of 1m$0 22mor 1m__FILE__22m) and the optimiza-
       tion can be disabled by enabling the 1mdisable_exec_load 22msetting.

   1mShelling out0m
       Any Ruby code that opens a subshell (like 1msystem22m, backticks,  or  1m%x{}22m)
       will  automatically use the current Bundler environment. If you need to
       shell out to a Ruby command that is not part of	your  current  bundle,
       use  the  1mwith_clean_env  22mmethod  with  a  block. Any subshells created
       inside the block will be given the environment present  before  Bundler
       was  activated. For example, Homebrew commands run Ruby, but don't work
       inside a bundle:



	   Bundler.with_clean_env do
	     `brew install wget`
	   end



       Using 1mwith_clean_env 22mis also necessary if you are  shelling  out  to  a
       different  bundle.  Any Bundler commands run in a subshell will inherit
       the current Gemfile, so commands that need to run in the context  of  a
       different bundle also need to use 1mwith_clean_env22m.



	   Bundler.with_clean_env do
	     Dir.chdir "/other/bundler/project" do
	       `bundle exec ./script`
	     end
	   end



       Bundler	provides  convenience  helpers	that wrap 1msystem 22mand 1mexec22m, and
       they can be used like this:



	   Bundler.clean_system('brew install wget')
	   Bundler.clean_exec('brew install wget')



1mRUBYGEMS PLUGINS0m
       At present,  the  Rubygems  plugin  system  requires  all  files  named
       1mrubygems_plugin.rb  22mon the load path of 4many24m installed gem when any Ruby
       code requires 1mrubygems.rb22m. This includes executables installed into the
       system, like 1mrails22m, 1mrackup22m, and 1mrspec22m.

       Since  Rubygems	plugins can contain arbitrary Ruby code, they commonly
       end up activating themselves or their dependencies.

       For instance, the 1mgemcutter 0.5 22mgem depended on 1mjson_pure22m. If	you  had
       that  version of gemcutter installed (even if you 4malso24m had a newer ver-
       sion without this problem), Rubygems would activate 1mgemcutter	0.5  22mand
       1mjson_pure <latest>22m.

       If your Gemfile(5) also contained 1mjson_pure 22m(or a gem with a dependency
       on 1mjson_pure22m), the latest version on your system  might  conflict  with
       the  version  in  your Gemfile(5), or the snapshot version in your 1mGem-0m
       1mfile.lock22m.

       If this happens, bundler will say:



	   You have already activated json_pure 1.4.6 but your Gemfile
	   requires json_pure 1.4.3. Consider using bundle exec.



       In this situation, you almost certainly want to remove  the  underlying
       gem  with  the problematic gem plugin. In general, the authors of these
       plugins (in this case, the 1mgemcutter 22mgem) have released newer  versions
       that are more careful in their plugins.

       You can find a list of all the gems containing gem plugins by running



	   ruby -rubygems -e "puts Gem.find_files('rubygems_plugin.rb')"



       At the very least, you should remove all but the newest version of each
       gem plugin, and also remove all gem plugins that you aren't using  (1mgem0m
       1muninstall gem_name22m).



				 January 2017			BUNDLE-EXEC(1)
