[ruby-cvs:66821] hsbt:r59643 (trunk): Fixed regression to convert blank value at r45497.

[hsbt at ruby-lang.org]

hsbt	2017-08-22 15:57:00 +0900 (Tue, 22 Aug 2017)

  New Revision: 59643

  https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=59643

  Log:
    Fixed regression to convert blank value at r45497.
    
      [Bug #11126][ruby-core:69088]

  Modified files:
    trunk/lib/csv.rb
    trunk/test/csv/test_data_converters.rb