(MODULES-2516) Adds an is_a() function

The data type system is very hard to understand. Many people don't
understand why

    type_of([1,2,3]) == Array

will fail, but

    type_of([1,2,3]) <= Array

passes. This does a simpler validation that doesn't rely on explicit
data types. Instead, use

    $foo = [1,2,3]
    if $foo.is_a(Array) {
      notify { 'This is an array': }
    }

This is based on code by Ben Ford <ben.ford@puppetlabs.com>.

  * Added acceptance tests
  * Added dispatch
  * Improved unit tests
  * Added docs to README

1 files changed, 28 insertions, 0 deletions

diff --git a/spec/acceptance/is_a_spec.rb b/spec/acceptance/is_a_spec.rb
new file mode 100644
index 0000000..533673c
--- /dev/null
+++ b/spec/acceptance/is_a_spec.rb
@@ -0,0 +1,28 @@
+#! /usr/bin/env ruby -S rspec
+require 'spec_helper_acceptance'
+
+describe 'is_a function', :unless => UNSUPPORTED_PLATFORMS.include?(fact('operatingsystem')) do
+  it 'should match a string' do
+    pp = <<-EOS
+    if 'hello world'.is_a(String) {
+      notify { 'output correct': }
+    }
+    EOS
+
+    apply_manifest(pp, :catch_failures => true) do |r|
+      expect(r.stdout).to match(/Notice: output correct/)
+    end
+  end
+
+  it 'should not match a integer as string' do
+    pp = <<-EOS
+    if 5.is_a(String) {
+      notify { 'output wrong': }
+    }
+    EOS
+
+    apply_manifest(pp, :catch_failures => true) do |r|
+      expect(r.stdout).not_to match(/Notice: output wrong/)
+    end
+  end
+end