`invert_where` inverts all where clause (dangerous!)

invert_where.rb

# frozen_string_literal: true

require "bundler/inline"

gemfile(true) do
  source "https://rubygems.org"

  git_source(:github) { |repo| "https://github.com/#{repo}.git" }

  # Activate the gem you are reporting the issue against.
  gem "activerecord", github: 'rails/rails'
  gem "activemodel", github: 'rails/rails'
  gem "activesupport", github: 'rails/rails'
  gem "sqlite3"
end

require "active_record"
require "logger"

# This connection will do for database-independent bug reports.
ActiveRecord::Base.establish_connection(adapter: "sqlite3", database: ":memory:")

ActiveRecord::Schema.define do
  create_table :posts, force: true do |t|
    t.string :a
    t.string :b
  end
end

class Post < ActiveRecord::Base
  has_many :comments
end

puts
puts

puts Post.where(a: 'a').where(b: 'b').to_sql
puts Post.where(a: 'a').where(b: 'b').invert_where.to_sql

result.md

$ ruby invert_where.rb
Fetching https://github.com/rails/rails.git
Fetching gem metadata from https://rubygems.org/......
Fetching gem metadata from https://rubygems.org/............
Fetching gem metadata from https://rubygems.org/............
Resolving dependencies...
Using bundler 2.2.15
Using concurrent-ruby 1.1.8
Using sqlite3 1.4.2
Using minitest 5.14.4
Using i18n 1.8.10
Using zeitwerk 2.4.2
Using tzinfo 2.0.4
Using activesupport 7.0.0.alpha from https://github.com/rails/rails.git (at main@adc0146)
Using activemodel 7.0.0.alpha from https://github.com/rails/rails.git (at main@adc0146)
Using activerecord 7.0.0.alpha from https://github.com/rails/rails.git (at main@adc0146)
-- create_table(:posts, {:force=>true})
   -> 0.0032s


SELECT "posts".* FROM "posts" WHERE "posts"."a" = 'a' AND "posts"."b" = 'b'
SELECT "posts".* FROM "posts" WHERE NOT ("posts"."a" = 'a' AND "posts"."b" = 'b')