Output number of table created from schema.rb or structure.sql, add polymorphic models count

[hmdros]

Closes #31

• Add an entry to CHANGELOG.md that links to this PR under the "main (unreleased)" heading.

Description:

Adds to the output:

• number of table created from schema.rb or structure.sql
• STI count
• polymorphic models count

I will abide by the code of conduct.

[codecov]

Codecov Report

Attention: Patch coverage is 84.74576% with 9 lines in your changes missing coverage. Please review.

Project coverage is 83.20%. Comparing base (8f3974d) to head (3a87be4).
Report is 7 commits behind head on main.

Files with missing lines	Patch %	Lines
lib/rails_stats/console_formatter.rb	76.92%	3 Missing ⚠️
lib/rails_stats/json_formatter.rb	80.00%	3 Missing ⚠️
lib/rails_stats/stats_calculator.rb	90.32%	3 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main      #37      +/-   ##
==========================================
+ Coverage   82.86%   83.20%   +0.33%     
==========================================
  Files          19       19              
  Lines         683      750      +67     
==========================================
+ Hits          566      624      +58     
- Misses        117      126       +9     

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[etagwerker]

@hmdros Thanks for submitting this!

This is outside of the scope of #31:

STI models count: 1 STI classes

And it can be quite complex to implement.

Could you please submit a new issue about STIs?

I think we could merge this PR without the STIs code and then you can work on the STIs code in a separate PR.

Thank you!

[etagwerker]

@hmdros I think this is too optimistic and it will generate false positives in certain applications.

Many projects use app/models as a place to put models that don't necessarily extend an ActiveRecord::Base|ApplicationRecord descendant.

I see that in your test you have this example:

class Pets < User
end

That's certainly an STI.

But what if someone has this in their app/models directory:

class Pets < User
end

And then:

class User 
...
end

That is not an STI and it will be counted as one (or two?)

[hmdros]

I do agree that this can get confusing and the code to check this would need to be extra careful for this. I can try to get this in a different PR then. Removing