You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: popover_test.rb
    path of file: ./repos/view_components/test/components/beta
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require "components/test_helper"

class PrimerBetaPopoverTest < Minit
    
  def test_allows_heading_customization
    render_inline(Primer::Beta::Popover.new) do |component|
      component.with_body { "Foo" }
      component.with_heading(mb: 4, pr: 3, tag: :h3) do
        "Hello world"
      end
    end

    assert_selector("div.Popover div.Popover-message.Box h3.mb-4.pr-3", text: "Hello world")
  end