Merge pull request #123 from chef/powershell

Add a cop for detecting legacy powershell methods

config/chefstyle.yml

@@ -713,4 +713,9 @@ Chef/Ruby/GemspecRequireRubygems:
 Chef/Ruby/RequireNetHttps:
   Description: net/https is deprecated and just includes net/http and openssl. We should include those directly instead
   Enabled: true
-  VersionAdded: '1.3.0'
+  VersionAdded: '1.3.0'
+
+Chef/Ruby/LegacyPowershellOutMethods:
+  Description: Use powershell_exec!/powershell_exec instead of the slower legacy powershell_out!/powershell_out methods.
+  Enabled: true
+  VersionAdded: '1.6.0'

lib/rubocop/cop/chef/ruby/legacy_powershell_out_methods.rb

@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+#
+# Copyright:: Chef Software, Inc.
+# Author:: Tim Smith (<tsmith@chef.io>)
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+module RuboCop
+  module Cop
+    module Chef
+      module Ruby
+        # Use powershell_exec!/powershell_exec instead of powershell_out!/powershell_out. The new
+        # methods don't spawn 2 shells per shellout and instead use .NET bindings to call PS directly.
+        class LegacyPowershellOutMethods < Base
+          MSG = "Use powershell_exec!/powershell_exec instead of the slower legacy powershell_out!/powershell_out methods."
+          RESTRICT_ON_SEND = %i{powershell_out! powershell_out}.freeze
+
+          def on_send(node)
+            add_offense(node, message: MSG, severity: :refactor)
+          end
+        end
+      end
+    end
+  end
+end

spec/rubocop/cop/chef/ruby/legacy_powershell_out_methods_spec.rb

@@ -0,0 +1,45 @@
+# frozen_string_literal: true
+#
+# Copyright:: Chef Software, Inc.
+# Author:: Tim Smith (<tsmith@chef.io>)
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+# http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+#
+
+require "spec_helper"
+
+describe RuboCop::Cop::Chef::Ruby::LegacyPowershellOutMethods, :config do
+  subject(:cop) { described_class.new(config) }
+
+  it "registers an offense when using powershell_out!" do
+    expect_offense(<<~RUBY)
+    powershell_out!('foo')
+    ^^^^^^^^^^^^^^^^^^^^^^ Use powershell_exec!/powershell_exec instead of the slower legacy powershell_out!/powershell_out methods.
+    RUBY
+  end
+
+  it "registers an offense when using powershell_out" do
+    expect_offense(<<~RUBY)
+    powershell_out('foo')
+    ^^^^^^^^^^^^^^^^^^^^^ Use powershell_exec!/powershell_exec instead of the slower legacy powershell_out!/powershell_out methods.
+    RUBY
+  end
+
+  it "doesn't register an when using powershell_exec" do
+    expect_no_offenses("powershell_exec('foo')")
+  end
+
+  it "doesn't register an when using powershell_exec!" do
+    expect_no_offenses("powershell_exec!('foo')")
+  end
+end