iis_config errors on collection properties

[habelson]

Cookbook version

6.8.0

Chef-client version

14.0.202

Platform Details

Windows Server 2016

Scenario:

When setting a property that that can have more than one of the same section, iis_config succeeds on first run, but fails on subsequent runs.

Steps to Reproduce:

iis_config '/section:applicationPools -+"applicationPoolDefaults.recycling.periodicRestart.schedule.[value=\'01:00:00\']" /commit:apphost' do
  action :set
end

Expected Result:

chef-client run succeeds on subsequent runs

Actual Result:

chef-client succeeds on first run, but fails on subsequent runs:

ERROR ( message:New add object missing required attributes. Cannot add duplicate collection entry of type 'add' with unique key attribute 'value' set to '01:00:00' . )

###Comments:
I'm aware this issue is related to #276 and that there is current work in progress to replace this feature with something better. I just wanted to make you aware of this edge case, in case it also comes up in the new code.