test_rubocop_overfetch.rb

# frozen_string_literal: true
require "graphql/client/erb"
require "rubocop/cop/graphql/overfetch"
require "minitest/autorun"

class TestRubocopOverfetch < Minitest::Test
  Root = File.expand_path("..", __FILE__)

  def setup
    config = RuboCop::Config.new
    @cop = RuboCop::Cop::GraphQL::Overfetch.new(config)
  end

  def test_all_fields_used
    result = investigate(@cop, "#{Root}/views/users/show.html.erb")

    assert_empty result.offenses.map(&:message)
  end

  def test_all_fields_used_with_safe_navigation_operator
    skip if RUBY_VERSION < "2.3"

    result = investigate(@cop, "#{Root}/views/users/show-2-3.html.erb")

    assert_empty result.offenses.map(&:message)
  end

  def test_field_unused
    result = investigate(@cop, "#{Root}/views/users/overfetch.html.erb")

    assert_equal 1, result.offenses.count
    assert_equal "GraphQL/Overfetch: GraphQL field 'birthday' query but was not used in template.", result.offenses.first.message
  end

  private

  def investigate(cop, path)
    engine = GraphQL::Client::ERB.new(File.read(path))
    processed_source = RuboCop::ProcessedSource.new(engine.src.dup, RUBY_VERSION.to_f, path)
    commissioner = RuboCop::Cop::Commissioner.new([cop], [cop], raise_error: true)
    commissioner.investigate(processed_source)
  end
end