Rubocop-rspec: Potentially misleading guidance for InstanceVariable cop

[andyw8]

"Use let instead of an instance variable" doesn't make sense in cases where an instance variable is used unnecessarily rather than a local variable. For example within a before block, assuming @foo isn't used anywhere else:

before do
  @foo = 'bar'
  widget.stub(@foo)
end

[pirj]

It might still be used somewhere in the shared example, and we won't be able to detect that usage.
Did you have a more generic message in mind, like "Don't use an instance variable"?

[andyw8]

How about: "Avoid instance variables – use let, a method call, or a local variable (if possible)"

[pirj]

This sounds just right.
@bquorning @Darhazer WDYT? I can make this change quickly.

[bquorning]

I like it.