INFRA-507 Added ip_range_size() and associated unit tests

lib/puppet/parser/functions/ip_range_size.rb

@@ -0,0 +1,16 @@
+# ex: syntax=ruby ts=2 sw=2 si et
+# frozen_string_literal: true
+
+begin
+  require 'puppetx/ip'
+rescue LoadError
+  # work around for puppet bug SERVER-973
+  Puppet.info('Puppet did not autoload from the lib directory... falling back to relative path load.')
+  require File.join(File.expand_path(File.join(__FILE__, '../../../..')), 'puppetx/ip')
+end
+
+module Puppet::Parser::Functions
+  newfunction(:ip_range_size, type: :rvalue) do |args|
+    PuppetX::Ip.new(args[0]).range_size(args[1]).to_i
+  end
+end

lib/puppetx/ip.rb

@@ -49,6 +49,15 @@ def offset
     address.to_i - cidr.to_i
   end
 
+  def range_size(range_cidr)
+    other_address = IPAddr.new(range_cidr.split(%r{/})[0])
+    raise ArgumentError, 'Both addresses must be in same family' if other_address.family != address.family
+
+    # Range size should be inclusive of starting and ending addresses, hence +1
+    range_subtraction = other_address.to_i - address.to_i
+    range_subtraction.abs + 1
+  end
+
   def split
     [ subnet(prefixlength + 1, 0), subnet(prefixlength + 1, 1) ]
   end
@@ -72,6 +81,15 @@ def to_s
     address.to_s
   end
 
+  def family
+    case address.family
+    when Socket::AF_INET
+      'IPv4'
+    when Socket::AF_INET6
+      'IPv6'
+    end
+  end
+
   private
 
   def unicast_prefixlength

metadata.json

@@ -1,6 +1,6 @@
 {
   "name": "inkblot-ipcalc",
-  "version": "2.2.1",
+  "version": "2.3.0",
   "author": "inkblot",
   "summary": "IP and subnet puppet parser functions",
   "license": "Apache-2.0",

spec/functions/ip_range_size_spec.rb

@@ -0,0 +1,49 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe 'ip_range_size' do
+  # please note that these tests are examples only
+  # you will need to replace the params and return value
+  # with your expectations
+  it 'given adjacent IPv4 CIDR addresses, returns range size of 2' do
+    is_expected.to run.with_params('192.168.1.1/32', '192.168.1.2/32').and_return(2)
+  end
+  it 'given adjacent IPv6 CIDR addresses, returns range size of 2' do
+    is_expected.to run.with_params('2001:db8::8c28:c929:72db:49fd/64', '2001:db8::8c28:c929:72db:49fe/64').and_return(2)
+  end
+  it 'given adjacent IPv4 plain addresses, returns range size of 2' do
+    is_expected.to run.with_params('192.168.1.1', '192.168.1.2').and_return(2)
+  end
+  it 'given adjacent IPv6 plain addresses, returns range size of 2' do
+    is_expected.to run.with_params('2001:db8::8c28:c929:72db:49fd', '2001:db8::8c28:c929:72db:49fe').and_return(2)
+  end
+  it 'given adjacent IPv4 plain addresses in reversed order, returns range size of 2' do
+    is_expected.to run.with_params('192.168.1.2', '192.168.1.1').and_return(2)
+  end
+  it 'given adjacent IPv6 plain addresses in reversed order, returns range size of 2' do
+    is_expected.to run.with_params('2001:db8::8c28:c929:72db:49fe', '2001:db8::8c28:c929:72db:49fd').and_return(2)
+  end
+  it 'given IPv4 CIDR addresses with same offset in different /24 networks, returns range size of 257' do
+    is_expected.to run.with_params('192.168.1.1/24', '192.168.2.1/24').and_return(257)
+  end
+  it 'given IPv6 CIDR addresses with same offset in different /56 networks, returns range size of 257' do
+    is_expected.to run.with_params('2001:db8::8c28:c929:72db:49fe/56', '2001:db8::8c28:c929:72db:4afe/56').and_return(257)
+  end
+  it 'given IPv4 plain addresses in wildly different networks, returns correct range size' do
+    is_expected.to run.with_params('10.0.57.1', '192.168.2.1').and_return(3_064_449_281)
+  end
+  it 'given IPv6 plain addresses in wildly different networks, returns correct range size' do
+    is_expected.to run
+      .with_params('2001:db8::8c28:c929:72db:49fe/64', 'fe80::9656:d028:8652:66b6/64')
+      .and_return(295_747_758_515_978_496_797_848_443_371_614_837_945)
+  end
+  it 'given addresses in different families, raises an exception' do
+    is_expected.to run
+      .with_params('10.0.57.1', 'fe80::9656:d028:8652:66b6')
+      .and_raise_error(ArgumentError, %r{addresses must be in same family})
+    is_expected.to run
+      .with_params('fe80::9656:d028:8652:66b6', '10.0.57.1')
+      .and_raise_error(ArgumentError, %r{addresses must be in same family})
+  end
+end