Using more of the build-in goodness chefspec provides to simplify things even further. We can run expectations against the chef runner directly.

hwrp_and_chefspec.rb

# I wanted to find a way to unit test a "Heavy-Weight" provider, but all the examples I found ended up stubbing out
# the chef world to make sure we could verify functionality as well as prevent the provider from converging on the
# development machine.
#
# I started thinking that chefspec already isolates things, and provides a great suite of matchers that we can 
# use to check on the creation of chef resources inside our heavy provider.  This is one approach that allows
# testing a single provider method, without a full chef run, in "isolation," with the helpful chefspec matchers.

# In my spec_helper

class ChefSpec::UnitRunner < ChefSpec::Runner

  def step_into?(*args)
    false
  end

  def compiling?
    false
  end

  def run_context
    @run_context ||= Chef::RunContext.new(node, {}, Chef::EventDispatch::Dispatcher.new)
  end

end


# Provider Spec

subject(:provider) do
  Chef::Provider::MyProvider.new(resource, runner.run_context).tap do |p|
    p.load_current_resource
  end
end

let(:runner) do
  ChefSpec::UnitRunner.new do |node|
    node.automatic['platform'] = 'redhat'
    node.automatic['platform_version'] = '6.4'
    node.automatic['fqdn'] = 'rspec-host'
    node.automatic['hostname'] = 'rspec-host'
  end
end

let(:resource) do
  Chef::Resource::MyResource.new("resourcename").tap do |r|
    r.attribute_one "value"
  end
end


it "creates the basic config files" do
  provider.create_base_templates
  expect(runner).to create_template("/etc/my-settings.conf")
end

# Provider method


def create_base_templates

  template "/etc/my-settings.conf" do
    mode 0644
  end.run_action(:create)
  
end