Jira (PUP-11505) Unexpected results using stdlib's to_yaml with data containing repeated variables

[Alexander Fisher (Jira)]

Title: Message Title

Alexander Fisher updated an issue   Puppet / PUP-11505 Unexpected results using stdlib's to_yaml with data containing repeated variables Change By: Alexander Fisher *Puppet Version: 6/7* I wasn't sure where to file this, but I encountered some unexpected behaviour today. Given the following puppet code {code:puppet}$array = [  'one',  'two',  'three'] notice(   {     'foo'      => $array,     'bar'      => $array,     'foobar' => $array,   }.to_yaml ) # These `flatten`s look superfluous, but aren't notice(   {     'foo'      => $array.flatten,     'bar'      => $array.flatten,     'foobar' => $array.flatten,   }.to_yaml ) {code} I'd expect to notice the same YAML being output.  Instead, in the version where I don't, (seemingly randomly call `flatten`), I get yaml with anchors (which I happen not to like). ie  {noformat}❯ puppet apply -t test.pp Info: Loading facts Notice: Scope(Class[main]): --- foo: &1 - one - two - three bar: *1 foobar: *1 Notice: Scope(Class[main]): --- foo: - one - two - three bar: - one - two - three foobar: - one - two - three {noformat} Whilst I understand that there's an issue with values being passed to the to_yaml function by reference and `flatten` gets around this by creating 3 new objects, I don't feel this meets the [https://en.wikipedia.org/wiki/Principle_of_least_astonishment] test. I don't think it's documented anywhere that _puppet_ variables can act this way with functions. Add Comment   This message was sent by Atlassian Jira (v8.20.2#820002-sha1:829506d) -- You received this message because you are subscribed to the Google Groups "Puppet Bugs" group. To unsubscribe from this group and stop receiving emails from it, send an email to puppet-bugs+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/puppet-bugs/JIRA.443443.1649780627000.10565.1649781060051%40Atlassian.JIRA.