envutil.rb: signal in Process::Status

* test/ruby/envutil.rb (assert_ruby_status): show status info.

* test/ruby/envutil.rb (Test::Unit::Assertions::FailDesc): use
  Signal.signame for consistency with Process::Status#inspect.

* signal.c (siglist): prefer SIGABRT over SIGIOT in Signal.signame.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39924 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* test/ruby/test_method.rb (test_unlinked_method_entry_in_method_object_bug):
  move from KNOWNBUGS.rb.  [Bug #8100]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39925 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
envutil.rb: separate checks

* test/ruby/envutil.rb (assert_ruby_status): separate abort check and
  exit status check.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39926 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
test_method.rb: refine assertions

* test/ruby/test_method.rb (test_unlinked_method_entry_in_method_object_bug):
  use assert_normal_exit since subject code never exit successfully,
  but check if timed out paranoically.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39927 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
string.c: performance improvement

* string.c (rb_str_rpartition): get rid of conversion from byte offset
  to char offset and backward, for performance improvement.

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@39928 b2dd03c8-39d4-4d8f-98ff-823fe69b080e