Issue #8408 has been reported by naruse (Yui NARUSE).

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Bug #8408: minitest's test may fail randomly
https://bugs.ruby-lang.org/issues/8408

Author: naruse (Yui NARUSE)
Status: Assigned
Priority: Normal
Assignee: zenspider (Ryan Davis)
Category: lib
Target version: current: 2.1.0
ruby -v: ruby 2.1.0dev (2013-05-15 trunk 40752) [x86_64-freebsd9.1]
Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN


test/minitest/test_minitest_spec.rb may fail as following:
http://c5664.rubyci.org/~chkbuild/ruby-trunk/log/20130515T013301Z.log.html.gz

  9) Failure:
TestMeta#test_structure_subclasses [/home/chkbuild/build/20130515T013301Z/ruby/test/minitest/test_minitest_spec.rb:751]:
Expected #<#<Class:0x002abd3bcfd7f8>:0x002abd3bf000f0 @__name__=nil, @__io__=nil, @passed=nil> (top-level thingy::inner) to respond to #xyz.

 10) Failure:
TestMeta#test_name [/home/chkbuild/build/20130515T013301Z/ruby/test/minitest/test_minitest_spec.rb:668]:
Expected: "ExampleA"
  Actual: "top-level thingy::ExampleA"

 11) Failure:
TestMeta#test_structure [/home/chkbuild/build/20130515T013301Z/ruby/test/minitest/test_minitest_spec.rb:687]:
--- expected
+++ actual
@@ -1 +1 @@
-"top-level thingy"
+"top-level thingy::top-level thingy"


 12) Failure:
TestMeta#test_name2 [/home/chkbuild/build/20130515T013301Z/ruby/test/minitest/test_minitest_spec.rb:680]:
Expected: "ExampleA"
  Actual: "top-level thingy::ExampleA"


It seems because of minitest's bug.
minitest's parallelize_me! make tests parallell but its describe method uses single stack.


-- 
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