eval_error.c: fix underflow

* eval_error.c (print_errinfo): get rid of negative string length.
  [ruby-core:86086] [Bug #14598]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@62728 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 8 insertions, 0 deletions

diff --git a/test/ruby/test_exception.rb b/test/ruby/test_exception.rb
index bb70bf508f..6532fecea9 100644
--- a/test/ruby/test_exception.rb
+++ b/test/ruby/test_exception.rb
@@ -1254,5 +1254,13 @@ $stderr = $stdout; raise "\x82\xa0"') do |outs, errs, status|
 
     _, err2, status1 = EnvUtil.invoke_ruby(['-e', "#{test_method}; begin; foo; end"], '', true, true)
     assert_equal(err2, out1)
+
+    if $stderr.tty?
+      e = RuntimeError.new("a\n")
+      message = assert_nothing_raised(ArgumentError, proc {e.pretty_inspect}) do
+        e.full_message
+      end
+      assert_operator(message, :end_with?, "\n")
+    end
   end
 end