RBENV_VERSION ignored when shelling out from ruby

[bronson]

This shows that RBENV_VERSION works when executed from Perl but not from Ruby. In this example, global version is set to 1.9.2p290.

$ ruby --version
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-linux]
$ perl -e 'system("RBENV_VERSION=system ruby -e \"puts RUBY_VERSION\"")'
1.8.7
$ ruby -e 'system("RBENV_VERSION=system ruby -e \"puts RUBY_VERSION\"")'
1.9.2

RBENV_VERSION should always work, shouldn't it?

[bronson]

That commit fixes this issue. Now I get the expected results:

$ ruby --version
ruby 1.9.2p290 (2011-07-09 revision 32553) [x86_64-linux]
$ ruby -e 'system("RBENV_VERSION=system ruby -e \"puts RUBY_VERSION\"")'
1.8.7
$ rbenv shell system
$ ruby -e 'system("RBENV_VERSION=1.9.2-p290 ruby -e \"puts RUBY_VERSION\"")'
1.9.2

Is it good enough to be merged? Or does issue #95 require the bin path to come before the shim path?

I'd really like to find a good solution to this. Thanks!

[bronson]

I mean, does the rbenv -S issue mentioned in #95 (#95 (comment)) require the bin path to come before the shim path?

[bronson]

This is still an issue in 0.3.0.

[mislav]

Your problem is that, when calling your script from ruby, you have already gone through rbenv to reach the ruby. So, PATH is already set up.

However from ruby you're calling ruby again, and this time it never hits the rbenv shim… because PATH is already set up and ruby is available right there on the top, rbenv is skipped completely and you're locked into the same version of ruby which you first activated.

I don't know whether this is a bug, or how to solve it. It seems unsolvable from rbenv. If from a ruby process you want to shell out to rbenv, you would need to edit ENV['PATH'] first to restore it to the pristine state.

[sheerun]

Maybe rbenv should remove from PATH any paths that contain RBENV_ROOT before appending anything?

imho that's bug. nothing should prevent running other version of ruby from ruby script.

[mislav]

It's a common pitfall. You can clear the current env from a Ruby process like so:

rbenv_root = `rbenv root 2>/dev/null`.chomp

unless rbenv_root.empty?
  re = /^#{Regexp.escape rbenv_root}\/(versions|plugins|libexec)\b/
  paths = ENV["PATH"].split(":")
  paths.reject! {|p| p =~ re }
  ENV["PATH"] = paths.join(":")
end

[sheerun]

I think it should be rbenv responsibility, not ruby programmer.

[mislav]

True. I also don't think the above workaround is what users should be doing in the long run. However, that is what they need to do with the current version of rbenv (0.4).

You can also put this plugin in RBENV_ROOT/rbenv.d/exec/path_clean.bash:

# EXPERIMENTAL: clean up PATH of modifications made in rbenv.
# This DISABLES the feature added in 2a495dc for `ruby -S` compatibility.
path_without_rbenv() {
  local result=""
  local paths
  IFS=: paths=($PATH)

  for path in "${paths[@]}"; do
    if ! [[ "$path" =~ "${RBENV_ROOT}/versions/" || \
            "$path" =~ "${RBENV_ROOT}/plugins/"  || \
            "$path" == "${RBENV_ROOT}/libexec"   ]]; then
      result="${result}${path}:"
    fi
  done

  echo "${result%:}"
}

exec() {
  export PATH="$(path_without_rbenv)"
  builtin exec "$@"
}

[Sen]

+1 for this
switch to jruby in script not work for me.
seems "global" ruby always there. how to unset global ruby? or is there any trick for this?

[aslakhellesoy]

\o/

[bronson]

This is huge. Kick ass, Mislav.

[trogdoro]

I tried mutating the PATH so that it uses the 'ruby' shim, but rbenv still doesn't use the version from .ruby-version in the current dir:

Any ideas why?

The |... lines in this example represent the contents of files and output of shell commands.

/tmp/
  dir_with_ruby_1.8.7/
    .ruby-version
      | 1.8.7-p375

  invoke_ruby_with_popen3.rb
    | require 'open3'
    | output = Open3.popen3(
    |   {"PATH"=>"/Users/craig/.rbenv/shims:/usr/local/Cellar/rbenv/0.4.0/libexec:/usr/bin:/bin"},
    |   "ruby -v",
    |   :chdir=>"/tmp/dir_with_ruby_1.8.7"
    |   )
    | puts output[1].readlines.join('')

  $ ruby invoke_ruby_with_popen3.rb
    | /private/tmp/dir_with_ruby_1.8.7

[mislav]

@trogdoro Not sure what is happening, nor what's your use case. My general advice is to use which ruby to confirm that the call is really going to the rbenv ruby shim. Then check PWD and RBENV_DIR (if set) since those directories are where rbenv will search for .ruby-version. Also, remember that RBENV_VERSION if set has precedence over .ruby-version.

[trogdoro]

Woops, forgot to blank out the RBENV_VERSION var. Adding "RBENV_VERSION"=>"" to the hash fixes it:

/tmp/
    - invoke_ruby_with_popen3.rb
      | require 'open3'
      | output = Open3.popen3(
      |   {"RBENV_VERSION"=>"", "PATH"=>"/Users/craig/.rbenv/shims:/usr/local/Cellar/rbenv/0.4.0/libexec:/usr/bin:/bin"},
      |   "ruby -v",
      |   :chdir=>"/tmp/dir_with_ruby_1.8.7"
      |   )
      | puts output[1].readlines.join('')

  $ ruby invoke_ruby_with_popen3.rb
    | ruby 1.8.7 (2013-12-22 patchlevel 375) [i686-darwin12.5.0]

Thanks!

[mislav]

The fix of this was reverted in 95a039a so I'm reopening this.