XAUTOCLAIM throws NoMethodError if entry is nil

[wcmonty]

If an entry in the PEL is deleted, xautoclaim returns nil for the event in the response. When processing that event, it is passed to the HashifyStreamAutoclaim lambda where it throws an error because the lambda assumes there's an actual event. See the following sample script. I tested with v4.5.1, but it looks like the lambda is unchanged in the current version.

redis.xgroup(:create, 'key', 'group1', '$', mkstream: true)
# => "OK"
redis.xadd('key', { foo: :bar }, id: '1')
# => "1-0"
redis.xreadgroup('group1', 'consumer1', 'key', '>', count: 1)
# => {"key"=>[["1-0", {"foo"=>"bar"}]]}
redis.xdel('key', '1-0')
# => 1
redis.xautoclaim('key', 'group1', 'consumer2', 0, '0-0', count: 1)
# NoMethodError: undefined method `[]' for nil:NilClass
# 
#      'entries' => reply[1].map { |entry| [entry[0], entry[1].each_slice(2).to_h] }
#                                                ^^^
# from /usr/local/bundle/gems/redis-4.5.1/lib/redis.rb:3704:in `block (2 levels) in <class:Redis>'

This is similar to #905. It looks like Redis server is changing its behavior as of v7.0, so this will no longer be an issue.

I think the solution is to compact the array before we map over it.

[byroot]

Fixed in #1166