Low-level Java error printed on Errno::EPIPE exception #5003
Description
Environment
$ jruby -v
jruby 9.1.15.0 (2.3.3) 2017-12-07 929fde8 Java HotSpot(TM) 64-Bit Server VM 25.40-b25 on 1.8.0_40-b27 +jit [darwin-x86_64]
$ uname -a
Darwin Jankos-MacBook-Pro-2.local 17.3.0 Darwin Kernel Version 17.3.0: Thu Nov 9 18:09:22 PST 2017; root:xnu-4570.31.3~1/RELEASE_X86_64 x86_64
Expected Behavior
When writing to a broken pipe using IO.copy_stream, I expect Errno::EPIPE exception to be raised without anything else printed, as it is the case on MRI:
require "stringio"
read_pipe, write_pipe = IO.pipe
read_pipe.close
IO.copy_stream(StringIO.new("foo"), write_pipe)script.rb:6:in `write': Broken pipe (Errno::EPIPE)
from script.rb:6:in `copy_stream'
from script.rb:6:in `<main>'
Actual Behavior
On JRuby, in addition to the Errno::EPIPE exception, we get a java.io.IOException: Broken pipe internal exception also printed out:
java.io.IOException: Broken pipe
at sun.nio.ch.FileDispatcherImpl.write0(Native Method)
at sun.nio.ch.FileDispatcherImpl.write(FileDispatcherImpl.java:60)
at sun.nio.ch.IOUtil.writeFromNativeBuffer(IOUtil.java:93)
at sun.nio.ch.IOUtil.write(IOUtil.java:65)
at sun.nio.ch.SinkChannelImpl.write(SinkChannelImpl.java:167)
at org.jruby.RubyIO.transfer(RubyIO.java:4323)
at org.jruby.RubyIO.copy_stream(RubyIO.java:4205)
at org.jruby.RubyIO$INVOKER$s$0$2$copy_stream.call(RubyIO$INVOKER$s$0$2$copy_stream.gen)
at org.jruby.internal.runtime.methods.JavaMethod$JavaMethodN.call(JavaMethod.java:725)
at org.jruby.internal.runtime.methods.DynamicMethod.call(DynamicMethod.java:208)
at org.jruby.runtime.callsite.CachingCallSite.cacheAndCall(CachingCallSite.java:338)
at org.jruby.runtime.callsite.CachingCallSite.call(CachingCallSite.java:183)
at script.invokeOther6:copy_stream(script.rb:6)
at script.RUBY$script(script.rb:6)
at java.lang.invoke.MethodHandle.invokeWithArguments(MethodHandle.java:625)
at org.jruby.ir.Compiler$1.load(Compiler.java:95)
at org.jruby.Ruby.runScript(Ruby.java:831)
at org.jruby.Ruby.runNormally(Ruby.java:750)
at org.jruby.Ruby.runNormally(Ruby.java:768)
at org.jruby.Ruby.runFromMain(Ruby.java:581)
at org.jruby.Main.doRunFromMain(Main.java:417)
at org.jruby.Main.internalRun(Main.java:305)
at org.jruby.Main.run(Main.java:232)
at org.jruby.Main.main(Main.java:204)
Errno::EPIPE: Broken pipe - Broken pipe
copy_stream at org/jruby/RubyIO.java:4224
<main> at script.rb:6
Note that the behaviour is still the same, an Errno::EPIPE exception is still raised, but in addition to that java.io.IOException: Broken pipe stack trace is displayed, even when I rescue Errno::EPIPE. The thing is that in my case I'm expecting that Errno::EPIPE will be raised in certain scenarios, so this internal Java stack trace is something that I would prefer wasn't there, because no exception was actually raised.