Method reference error

[wojw5]

Steps to reproduce

Define ability with method reference instead of block.
Example:

can :read, Book, &:public?

Gist to reproduce:
https://gist.github.com/wojw5/d0f73e6457a8bbb1a976a07a991a5e93

Expected behavior

Error is not thrown, ability is checked

Actual behavior

method CanCan::ConditionsMatcher#matches_block_conditions consumes two arguments (subject, *extra_args), but it is called in with CanCan::ConditionsMatcher#matches_conditions? with three (subject, attribute, *extra_args).
It makes extra_args to be [nil] which is tried to be passed to method reference proc.

1) Error:
BugTest#test_bug:
ArgumentError: wrong number of arguments (given 1, expected 0)
    main.rb:25:in `public?'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/conditions_matcher.rb:24:in `matches_block_conditions'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/conditions_matcher.rb:8:in `matches_conditions?'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:77:in `block (2 levels) in can?'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:76:in `each'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:76:in `detect'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:76:in `block in can?'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `each'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `each'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `each'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `each'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `first'
    /Users/wojtek/.rvm/gems/ruby-2.5.5@cancancan/gems/cancancan-3.0.0/lib/cancan/ability.rb:79:in `can?'
    main.rb:47:in `test_bug'

1 runs, 0 assertions, 0 failures, 1 errors, 0 skips

System configuration

Rails version:
4.2.11 (not related)
Ruby version:
2.5.5 (not related)
CanCanCan version
3.0.0

[coorasse]

Yes, I confirm that this was working on cancancan 2.3.0