__rvm_unload obliterates PATH

[signe]

Description

Calling __rvm_unload in a script severely munges the environment, namely PATH, which makes further commands in the script impossible

Steps to reproduce

1. rvm get master
   also occurs in 1.29.9 — regression from 1.29.8
2. create script:

#!/bin/bash

source ~/.rvm/scripts/rvm
echo "---- BEFORE ----"
echo $PATH
echo "---- BEFORE ----"
__rvm_unload
echo "---- AFTER ----"
echo $PATH
echo "--- AFTER ----"

env

3. run script

Expected behavior

• Current path displayed between 'BEFORE'

• Same path, minus the ruby-specific entries, displayed between 'AFTER'

• Output using 1.29.8:

---- BEFORE ----
/home/user/.rvm/gems/ruby-2.6.3/bin:/home/user/.rvm/gems/ruby-2.6.3@global/bin:/home/user/.rvm/rubies/ruby-2.6.3/bin:/home/user/bin:.:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/home/user/.rvm/bin
---- BEFORE ----
---- AFTER ----
/home/user/bin:.:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin
--- AFTER ----
LC_ALL=C.UTF-8
[...]

Actual behavior

$ ./test.sh
---- BEFORE ----
/home/user/.rvm/gems/ruby-2.6.3/bin:/home/user/.rvm/gems/ruby-2.6.3@global/bin:/home/user/.rvm/rubies/ruby-2.6.3/bin:/home/user/bin:.:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/home/user/.rvm/bin
---- BEFORE ----
/home/user/.rvm/scripts/functions/support: line 277: awk: command not found
/home/user/.rvm/scripts/functions/env: line 187: sort: command not found
/home/user/.rvm/scripts/functions/env: line 187: cat: command not found
/home/user/.rvm/scripts/functions/support: line 277: awk: command not found
/home/user/.rvm/scripts/functions/support: line 277: awk: command not found
/home/user/.rvm/scripts/functions/support: line 260: grep: command not found
/home/user/.rvm/scripts/functions/env: line 187: sort: command not found
/home/user/.rvm/scripts/functions/env: line 187: cat: command not found
/home/user/.rvm/scripts/functions/env: line 234: sort: command not found
/home/user/.rvm/scripts/functions/support: line 277: awk: command not found
/home/user/.rvm/scripts/functions/support: line 260: grep: command not found
/home/user/.rvm/scripts/functions/env: line 187: sort: command not found
/home/user/.rvm/scripts/functions/env: line 187: cat: command not found
---- AFTER ----
.
--- AFTER ----
./test.sh: line 12: env: command not found

Environment info

$ rvm info

ruby-2.6.3:

  system:
    uname:        "Linux dev 4.15.0-1045-aws #47-Ubuntu SMP Fri Aug 2 13:50:30 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux"
    name:         "Ubuntu"
    version:      "18.04"
    architecture: "x86_64"
    bash:         "/bin/bash => GNU bash, version 4.4.20(1)-release (x86_64-pc-linux-gnu)"
    zsh:          "/usr/bin/zsh => zsh 5.4.2 (x86_64-ubuntu-linux-gnu)"
    remote_path:  "ubuntu/18.04/x86_64"

  rvm:
    version:      "1.29.9-next (master)"
    updated:      "11 minutes 37 seconds ago"
    path:         "/home/user/.rvm"
    autolibs:     "[enable] Allow RVM to use package manager if found, install missing dependencies, install package manager (only OS X)."

  ruby:
    interpreter:  "ruby"
    version:      "2.6.3p62"
    date:         "2019-04-16"
    platform:     "x86_64-linux"
    patchlevel:   "2019-04-16 revision 67580"
    full_version: "ruby 2.6.3p62 (2019-04-16 revision 67580) [x86_64-linux]"

  homes:
    gem:          "/home/user/.rvm/gems/ruby-2.6.3"
    ruby:         "/home/user/.rvm/rubies/ruby-2.6.3"

  binaries:
    ruby:         "/home/user/.rvm/rubies/ruby-2.6.3/bin/ruby"
    irb:          "/home/user/.rvm/rubies/ruby-2.6.3/bin/irb"
    gem:          "/home/user/.rvm/rubies/ruby-2.6.3/bin/gem"
    rake:         "/home/user/.rvm/gems/ruby-2.6.3/bin/rake"

  environment:
    PATH:         "/home/user/.rvm/gems/ruby-2.6.3/bin:/home/user/.rvm/gems/ruby-2.6.3@global/bin:/home/user/.rvm/rubies/ruby-2.6.3/bin:/home/user/bin:.:/home/user/bin:/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/snap/bin:/home/user/bin:/home/user/.rvm/bin"
    GEM_HOME:     "/home/user/.rvm/gems/ruby-2.6.3"
    GEM_PATH:     "/home/user/.rvm/gems/ruby-2.6.3:/home/user/.rvm/gems/ruby-2.6.3@global"
    MY_RUBY_HOME: "/home/user/.rvm/rubies/ruby-2.6.3"
    IRBRC:        "/home/user/.rvm/rubies/ruby-2.6.3/.irbrc"
    RUBYOPT:      ""
    gemset:       ""

[signe]

Caused by 913b407

If there is no rvm_gems_path, then "/*" gets passed to __rvm_remove_from_path.
Needs a guard to ensure that rvm_gems_path is set before calling.