(CAT-2432) Troubleshoot deferred resources in DSC

.gitignore

@@ -15,7 +15,6 @@
 /junit/
 /log/
 /pkg/
-/spec/fixtures/manifests/
 /spec/fixtures/modules/*
 /tmp/
 /vendor/

spec/acceptance/deferred_spec.rb

@@ -0,0 +1,38 @@
+# frozen_string_literal: true
+
+require 'spec_helper_acceptance'
+
+describe 'deferred values with dsc_lite' do
+  let(:control_manifest) do
+    File.read(File.join(__dir__, '..', 'fixtures', 'manifests', '01_file_deferred.pp'))
+  end
+
+  let(:dsc_deferred_direct) do
+    File.read(File.join(__dir__, '..', 'fixtures', 'manifests', '02_dsc_deferred_direct.pp'))
+  end
+
+  let(:dsc_deferred_var) do
+    File.read(File.join(__dir__, '..', 'fixtures', 'manifests', '03_dsc_deferred_in_variable.pp'))
+  end
+
+  it 'applies with native file + deferred (control succeeds)' do
+    idempotent_apply(control_manifest)
+    # optionally verify file contents
+    on(default, 'powershell.exe -NoProfile -NonInteractive -Command "(Get-Content -Raw C:/Temp/deferred_ok.txt)"') do |r|
+      expect(r.stdout).to match(%r{hello-world})
+    end
+  end
+
+  context 'dsc_lite with deferred' do
+    it 'fails when passing Deferred directly to a DSC property' do
+      # We currently expect failure (documenting the bug).
+      result = apply_manifest(dsc_deferred_direct, expect_failures: true)
+      expect(result.stderr + result.stdout).to match(%r{Deferred|serialize|to_json|downcase|implicit conversion}i)
+    end
+
+    it 'fails when assigning Deferred to a variable then to a DSC property' do
+      result = apply_manifest(dsc_deferred_var, expect_failures: true)
+      expect(result.stderr + result.stdout).to match(%r{Deferred|serialize|to_json|downcase|implicit conversion}i)
+    end
+  end
+end

spec/fixtures/manifests/01_file_deferred.pp

@@ -0,0 +1,5 @@
+# manifest: 01_file_deferred.pp
+file { 'C:/Temp/deferred_ok.txt':
+  ensure  => file,
+  content => Deferred('join', [['hello','-','world'], '']),
+}

spec/fixtures/manifests/02_dsc_deferred_direct.pp

@@ -0,0 +1,11 @@
+# manifest: 02_dsc_deferred_direct.pp
+dsc { 'WriteFileViaDSC':
+  dsc_resource_name => 'File',
+  dsc_module        => 'PSDesiredStateConfiguration',
+  properties        => {
+    'DestinationPath' => 'C:\Temp\from_dsc.txt',
+    'Type'            => 'File',
+    'Ensure'          => 'Present',
+    'Contents'        => Deferred('join', [['hello','-','dsc'], '']),
+  },
+}

spec/fixtures/manifests/03_dsc_deferred_in_variable.pp

@@ -0,0 +1,13 @@
+# manifest: 03_dsc_deferred_in_variable.pp
+$value = Deferred('join', [['hello','-','var'], ''])
+
+dsc { 'WriteFileViaDSCVar':
+  dsc_resource_name => 'File',
+  dsc_module        => 'PSDesiredStateConfiguration',
+  properties        => {
+    'DestinationPath' => 'C:\Temp\from_dsc_var.txt',
+    'Type'            => 'File',
+    'Ensure'          => 'Present',
+    'Contents'        => $value,  # still a Deferred wrapper at this point
+  },
+}