unbound_version: add spec tests to the unbound_version fact

lib/facter/unbound_version.rb

@@ -1,18 +1,11 @@
 # frozen_string_literal: true
 
-unbound_bin = case Facter.value('kernel')
-              when 'FreeBSD'
-                '/usr/local/sbin/unbound'
-              else
-                '/usr/sbin/unbound'
-              end
-if File.exist? unbound_bin
-  unbound_version = Facter::Util::Resolution.exec(
-    "#{unbound_bin} -V 2>&1"
-  ).match(%r{Version\s+(\d+(?:\.\d+)*)})[1]
-  Facter.add(:unbound_version) do
-    setcode do
-      unbound_version
+Facter.add(:unbound_version) do
+  confine { Facter.value(:kernel) != 'windows' }
+  setcode do
+    if Facter::Util::Resolution.which('unbound')
+      unbound_version = Facter::Util::Resolution.exec('unbound -V 2>&1')
+      %r{Version\s+(\d+(?:\.\d+){2})\s+}.match(unbound_version)[1]
     end
   end
 end

spec/spec_helper.rb

@@ -31,6 +31,7 @@
 end
 
 RSpec.configure do |c|
+  c.mock_with :rspec
   # Coverage generation
   c.after(:suite) do
     RSpec::Puppet::Coverage.report!

spec/unit/unbound/facter/unbound_version_spec.rb

@@ -0,0 +1,52 @@
+require 'spec_helper'
+
+version_string = <<-VERSION
+unbound: invalid option -- 'V'
+usage:  unbound [options]
+        start unbound daemon DNS resolver.
+-h      this help
+-c file config file to read instead of /etc/unbound/unbound.conf
+        file format is described in unbound.conf(5).
+-d      do not fork into the background.
+-v      verbose (more times to increase verbosity)
+Version %s
+linked libs: libevent 2.0.21-stable (it uses epoll), OpenSSL 1.1.0l  10 Sep 2019
+linked modules: dns64 python validator iterator
+BSD licensed, see LICENSE in source package for details.
+Report bugs to unbound-bugs@nlnetlabs.nl
+VERSION
+
+tests = {
+  'valid' => ['1.1.1', '1.90.24', '1.0.404', '2.5.6'],
+  'invalid' => ['1', '1.1', '1.1.1.1', '1,1,1', '2:5.1', 'foobar']
+}
+describe Facter::Util::Fact.to_s do
+  before { Facter.clear }
+  context 'unbound not in path' do
+    before do
+      allow(Facter::Util::Resolution).to receive(:which).with('unbound') { false }
+    end
+    it { expect(Facter.fact(:unbound_version).value).to eq(nil) }
+  end
+  tests.each_pair do |test, versions|
+    describe "test #{test} versions" do
+      before do
+        allow(Facter::Util::Resolution).to receive(:which).with('unbound') { true }
+      end
+      versions.each do |version|
+        context "test version #{version}" do
+          before do
+            allow(Facter::Util::Resolution).to receive(:exec).with('unbound -V 2>&1') do
+              version_string % version
+            end
+          end
+          if test == 'valid'
+            it { expect(Facter.fact(:unbound_version).value).to eq(version) }
+          else
+            it { expect(Facter.fact(:unbound_version).value).to eq(nil) }
+          end
+        end
+      end
+    end
+  end
+end