[ruby-cvs:67710] eregon:r60529 (trunk): Use ENV['RUBY_EXE'] as RbConfig.ruby might be incorrect

[eregon at ruby-lang.org]

eregon	2017-10-29 01:15:46 +0900 (Sun, 29 Oct 2017)

  New Revision: 60529

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=60529

  Log:
    Use ENV['RUBY_EXE'] as RbConfig.ruby might be incorrect
    
    * On a built-but-not-installed-ruby.

  Modified files:
    trunk/spec/ruby/optional/capi/spec_helper.rb