Fix spawn issue when given :close option

Author: bjfish

CHANGELOG.md

@@ -12,6 +12,7 @@ Bug fixes:
 * Fixed issue when extending FFI from File (#2094).
 * Fixed issue with `Kernel#freeze` not freezing singleton class (#2093).
 * Fixed `String#encode` with options issue (#2091, #2095, @LillianZ)
+* Fixed issue with `spawn` when `:close` redirect is used (#2097).
 
 Compatibility:
 

spec/ruby/core/process/spawn_spec.rb

@@ -536,6 +536,15 @@ def child_pids(pid)
     File.read(@name).should == "glarkbang"
   end
 
+  it "closes STDERR in the child if :err => :close" do
+    File.open(@name, 'w') do |file|
+      -> do
+        code = "begin; STDOUT.puts 'out'; STDERR.puts 'hello'; rescue => e; puts 'rescued'; end"
+        Process.wait Process.spawn(ruby_cmd(code), :out => file, :err => :close)
+      end.should output_to_fd("out\nrescued\n", file)
+    end
+  end
+
   # :close_others
 
   platform_is_not :windows do

spec/tags/core/process/spawn_tags.txt

@@ -80,3 +80,4 @@ slow:Process.spawn inside Dir.chdir does not create extra process without chdir
 slow:Process.spawn inside Dir.chdir kills extra chdir processes
 slow:Process.spawn redirects both STDERR and STDOUT to the given file descriptor
 slow:Process.spawn defaults :close_others to false
+slow:Process.spawn closes STDERR in the child if :err => :close

src/main/ruby/truffleruby/core/truffle/process_operations.rb

@@ -262,7 +262,12 @@ def parse_options(options)
 
       def redirect(from, to)
         map = (@options[:redirect_fd] ||= [])
-        map << from << to
+        if to.nil?
+          @options[:fds_to_close] ||= []
+          @options[:fds_to_close] << from
+        else
+          map << from << to
+        end
       end
 
       def convert_io_fd(obj)
@@ -491,6 +496,8 @@ def posix_spawnp(command, args, env_array, options)
             end
           when :chdir
             chdir = value
+          when :fds_to_close
+            value.each { |fd| fds_to_close << fd }
           else
             raise "Unknown spawn option: #{key}"
           end