BUG: ruby-yarv 1.9 undefined method `close' for nil:NilClass in ensure

Hello, 

irb(main):003:0* begin 
irb(main):004:1* foo = File.open("foo")
irb(main):005:1> ensure
irb(main):006:1* foo.close
irb(main):007:1> end
NoMethodError: undefined method `close' for nil:NilClass
        from (irb):6:in `ensure in irb_binding'
        from (irb):6
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:150:in `block (2 
levels) in eval_input'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:259:in 
`signal_status'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:147:in `block in 
eval_input'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:146:in `eval_input'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:70:in `block in 
start'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:69:in `catch'
        from /usr/local/ruby-1.9/lib/ruby/1.9/irb.rb:69:in `start'
        from /usr/local/ruby-1.9/bin/irb:13:in `<main>'
irb(main):008:0> quit
mulperi@mulperi-desktop:/usr/local/src/ruby-libs/rubygems-0.9.0$ ruby -v
ruby 1.9.0 (2007-01-04 patchlevel 0) [i686-linux]


Also 
make check fails for me as follows:

make check
not ok assignment 90 -- ./sample/test.rb:137:in `block in <main>'
not ok assignment 91 -- ./sample/test.rb:138:in `block in <main>'
not ok assignment 92 -- ./sample/test.rb:139:in `block in <main>'
not ok assignment 93 -- ./sample/test.rb:140:in `block in <main>'
not ok assignment 94 -- ./sample/test.rb:141:in `block in <main>'
not ok assignment 95 -- ./sample/test.rb:142:in `block in <main>'
not ok assignment 110 -- ./sample/test.rb:159:in `block in <main>'
not ok assignment 117 -- ./sample/test.rb:167:in `block in <main>'
not ok assignment 118 -- ./sample/test.rb:168:in `block in <main>'
not ok assignment 119 -- ./sample/test.rb:169:in `block in <main>'
not ok assignment 120 -- ./sample/test.rb:170:in `block in <main>'
not ok assignment 122 -- ./sample/test.rb:172:in `block in <main>'
not ok assignment 123 -- ./sample/test.rb:173:in `block in <main>'
not ok assignment 124 -- ./sample/test.rb:174:in `block in <main>'
not ok assignment 145 -- ./sample/test.rb:198:in `block in <main>'
not ok assignment 209 -- ./sample/test.rb:271:in `block in <main>'
not ok assignment 217 -- ./sample/test.rb:285:in `<main>'
not ok assignment 218 -- ./sample/test.rb:286:in `<main>'
not ok assignment 219 -- ./sample/test.rb:287:in `<main>'
not ok iterator 16 -- ./sample/test.rb:959:in `<main>'
not ok iterator 17 -- ./sample/test.rb:961:in `<main>'
not ok iterator 22 -- ./sample/test.rb:968:in `block in <main>'
not ok iterator 26 -- ./sample/test.rb:974:in `block in <main>'
not ok iterator 27 -- ./sample/test.rb:975:in `block in <main>'
not ok iterator 31 -- ./sample/test.rb:979:in `block in <main>'
not ok iterator 32 -- ./sample/test.rb:980:in `block in <main>'
not ok iterator 34 -- ./sample/test.rb:983:in `block in <main>'
not ok iterator 35 -- ./sample/test.rb:984:in `block in <main>'
not ok iterator 47 -- ./sample/test.rb:1035:in `<main>'
not ok iterator 49 -- ./sample/test.rb:1037:in `<main>'
not ok iterator 50 -- ./sample/test.rb:1038:in `<main>'
not ok iterator 63 -- ./sample/test.rb:1058:in `<main>'
not ok iterator 65 -- ./sample/test.rb:1060:in `<main>'
not ok iterator 82 -- ./sample/test.rb:1127:in `<main>'
not ok iterator 87 -- ./sample/test.rb:1166:in `<main>'
not ok iterator 88 -- ./sample/test.rb:1173:in `<main>'
not ok iterator 90 -- ./sample/test.rb:1186:in `<main>'
not ok iterator 92 -- ./sample/test.rb:1205:in `<main>'
not ok iterator 94 -- ./sample/test.rb:1223:in `<main>'
not ok iterator 95 -- ./sample/test.rb:1232:in `<main>'
not ok iterator 96 -- ./sample/test.rb:1242:in `<main>'
not ok iterator 98 -- ./sample/test.rb:1260:in `<main>'
not ok iterator 101 -- ./sample/test.rb:1280:in `<main>'
not ok iterator 102 -- ./sample/test.rb:1281:in `<main>'
not ok/test: 857 failed 44
test failed