Explanation for why `its` will be removed from rspec-3

explanation.md

its isn't core to RSpec. One the of the focuses of RSpec is on the documentation aspects of tests. Unfortunately, its often leads to documentation output that is essentially lies. Consider this spec:

User = Struct.new(:name, :email)

describe User do
  subject { User.new("bob") }
  its(:name) { should == "bob" }
end

$ bin/rspec user_spec.rb --format doc

User
  name
    should == "bob"

Finished in 0.00085 seconds
1 example, 0 failures

Randomized with seed 25153

It's not a true behavior of User#name that it always equals "bob". its generally leads to output that is true in a specific case, but false in the general case, and doesn't help understanding when reading the documentation output.

Those who like its tend to really like it and want to continue to evolve it to do more and more powerful and terse things, such as having it support arguments. We're uncomfortable with making its more and more meta (it's already meta enough!). We were planning on moving its into an external gem when we removed it from rspec-core, and @dnagir has already done that:

https://github.com/dnagir/its

Recently, we've also found some cases where there was some surprising, non-intuitive behavior with example groups that use subject and its:

rspec/rspec-core#768 (comment)

I think its gains you terseness at the expense of clarity, and in my judgement, it's a poor tradeoff.

I also feel like rspec-given is a better direction to go with one-liners. If you like one-liners, rspec-given encourages Given/When/Then one-liners, with no example docstrings at all. It's more of a unified vision for this kind of thing than the its method in rspec-core.

Finally, you can read @dchelimsky's thoughts on its from a while ago.

Revisiting our use of rspec-its, I ended up here, trying to really understand the decision behind the removal of the its syntax from the core, and to answer a simple questions: should we avoid its, and why?

Unfortunately, the example given in this gist does this issue a disservice: its gets blamed for the bad documentation output, but as others have already pointed out, the expectation can be written without, and this is exactly what I see a lot of people doing now that its has been removed from core:

it { expect(subject.name).to eq "bob" }

With this, the output becomes:

User
  should eq "bob"

If anything, this is worse. So why blame its?

I was interested in the mention of some surprising, non-intuitive behavior with example groups that use subject and its (rspec/rspec-core#768 (comment)). But if I read that thread correctly, it was actually a bug, and it has been fixed since then.

The only thing that kind of makes sense to me is the "uncomfortable with making its more and more meta" comment. I can see that as a valid reason to want to extract it into a separate gem, but still not a reason to avoid using it in its current just-enough-meta form...

I came here for understanding, but found only red herrings, no real answers, and I am still unclear whether its should be considered dangerous and avoided, or if it is perfectly OK to keep using it through rspec-its... My only takeaway is: people will write bad specs, with its or without.

I'd like to add that

its is forcing devs into 1 expect / case
have_attributes tends to lead dev to do exactly the opposite, aka drop all your shit in one test