[Bug] Check for required properties does not catch missing property

[dariok]

If required parameters are path and file, the current check will not report an error if only one of theses is given. This is down to the comparison function in body:ensure-required-properties() currently checking
$required-properties = $received-property-names

If at least one required property is present in the received properties, this comparison will always be true.

The intended (and correct) comparison from the function definition is ($required-prop-name = $received-property-names)