Kernel#system fails with out: $stdout #5865
Description
Environment
- Darwin Elia.local 18.7.0 Darwin Kernel Version 18.7.0: Tue Aug 20 16:57:14 PDT 2019; root:xnu-4903.271.2~2/RELEASE_X86_64 x86_64
Expected Behavior
⤑ ruby -ve 'system("echo hello world", out: $stdout)'
ruby 2.6.2p47 (2019-03-13 revision 67232) [x86_64-darwin18]
hello world
⤑
Actual Behavior
⤑ ruby -ve 'system("echo hello world", out: $stdout)' ~
jruby 9.2.6.0 (2.5.3) 2019-02-11 15ba00b Java HotSpot(TM) 64-Bit Server VM 25.25-b02 on 1.8.0_25-b17 +jit [darwin-x86_64]
NotImplementedError: cyclic redirects in child are not supported
system at org/jruby/RubyKernel.java:1661
<main> at -e:1
📝 Should be noted that this happens only using $stdout, with other out: destinations works fine:
⤑ ruby -ve 'system("echo hello world", out: $stderr)' ~
jruby 9.2.6.0 (2.5.3) 2019-02-11 15ba00b Java HotSpot(TM) 64-Bit Server VM 25.25-b02 on 1.8.0_25-b17 +jit [darwin-x86_64]
hello world
⤑ ruby -ve 'system("echo hello world", out: File.new("/tmp/foo.txt","w"))' ~
jruby 9.2.6.0 (2.5.3) 2019-02-11 15ba00b Java HotSpot(TM) 64-Bit Server VM 25.25-b02 on 1.8.0_25-b17 +jit [darwin-x86_64]
⤑ cat /tmp/foo.txt ~
hello world
⤑