[ruby-cvs:78609] 85e43e1dfe (master): Fix Enumerator::Lazy#with_index

Jeremy Evans	2019-12-11 06:38:12 +0900 (Wed, 11 Dec 2019)

  New Revision: 85e43e1dfe

  https://github.com/ruby/ruby/commit/85e43e1dfe

  Log:
    Fix Enumerator::Lazy#with_index
    
    * Make it correctly handle lambdas
    * Make it iterate over the block if block is given
    
    The original implementation was flawed, based on lazy_set_method
    instead of lazy_add_method.
    
    Note that there is no implicit map when passing a block, the return
    value of the block passed to with_index is ignored, just as it
    is for Enumerator#with_index. Also like Enumerator#with_index,
    when called with a block, the return value is an enumerator without
    the index.
    
    Fixes [Bug #16414]

  Modified files:
    enumerator.c
    test/ruby/test_lazy_enumerator.rb