Fix Layout/AlignHash when mixed Hash styles are used

[rmm5t]

Fixes #7066. Otherwise, this happens when mixed hash styles are used:

      {
        'Content-Type' => 'application/json',
        Authorization: "Bearer #{@access_token}",
      }

An error occurred while Layout/AlignHash cop was inspecting /Users/rmcgeary/work/ironridge/lib/salesforce/client.rb:72:6.
nil can't be coerced into Integer
.../gems/rubocop-0.70.0/lib/rubocop/cop/mixin/hash_alignment.rb:113:in `+'
.../gems/rubocop-0.70.0/lib/rubocop/cop/mixin/hash_alignment.rb:113:in `value_delta'
.../gems/rubocop-0.70.0/lib/rubocop/cop/mixin/hash_alignment.rb:65:in `deltas'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:239:in `block (2 levels) in check_pairs'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:238:in `each'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:238:in `block in check_pairs'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:237:in `each'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:237:in `check_pairs'
.../gems/rubocop-0.70.0/lib/rubocop/cop/layout/align_hash.rb:208:in `on_hash'

---

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[bbatsov]

Why isn't this a number in the first place? Probably we can convert it earlier and this would yield slightly better code.

[rmm5t]

Fair question. I found this code to be a tad hard to follow. This value is initialized to nil as an attr_accessor, and its usage expects deltas_for_first_pair to have been called first, but it apparently wasn’t under the particular scenario that caused the error.

Are you asking for an initializer that initializes this value to zero?

[rmm5t]

To clarify, for now, I’m just trying to keep the bug fix as small as possible considering there might be other syntax scenarios that we haven’t considered yet for the new AlignHash features.

[bquorning]

It’s probably related to AlignHash now being able to use a mix of e.g. TableAlignment and KeyAlignment, leading to – as you mention – TableAlignment#deltas_for_first_pair not being called before accessing max_key_width, and thus doing calculations with nil…

I agree that defaulting to 0 would be a good approach here.

[rmm5t]

Okay, I'll add a constructor to default the value to zero. Stand by.

[rmm5t]

Suggested changes pushed.

[bbatsov]

Thanks!