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: jemalloc_spec.rb
    path of file: ./repos/gitlabhq/spec/lib/gitlab/memory
    
    the code of the file until where you have to start completion: # frozen_string_literal: true

require 'fast_spec_helper'
require 'tempfile'

RSpec.describe Gitlab::Memory::Jemalloc do
  let(:outfile) { Tempfile.new }

  after do
    outfile.close
    outfile.unlink
  end

  context 'when jemalloc is loaded' do
    let(:fiddle_func) { instance_double(::Fiddle::Function) }

    context 'wi
    
  def stub_stats_call(output, expected_options = '')
    # Stub function pointer to stats call.
    func_pointer = Fiddle::Pointer.new(0xd34db33f)
    expect(::Fiddle::Handle).to receive(:sym).with('malloc_stats_print').and_return(func_pointer)

    # Stub actual function call.
    expect(::Fiddle::Function).to receive(:new)
      .with(func_pointer, anything, anything)
      .and_return(fiddle_func)
    expect(fiddle_func).to receive(:call).with(anything, nil, expected_options) do |callback, _, options|
      callback.call(nil, output)
    end
  end