In version 3.0.0 without the fix:
$ irb
irb(main):001:0' source 'a.rb'
a.rb(main):002:0> a = 'hi'
=> "hi"
=> nil
$

In version 3.0.0 with the fix:
$ irb
irb(main):001:0> source 'a.rb'
a.rb(main):002:0> a = 'hi'
=> "hi"
a.rb(main):003:0> 
=> nil
irb(main):003:0> puts a
hi
=> nil
irb(main):004:0> 

