Scope[] now returns nil for undefined variables

Given that we have the 'include?' method, this feature
is unnecessary, and it makes sense to convert to more
ruby-like behavior.

Any code that previously checked whether lookupvar
(or the new []) returned :undefined should now check
whether 'scope.include?(var)'.  Thus, you can have
the same behavior, but it takes a bit different code
to get it.

Signed-off-by: Luke Kanies <luke@puppetlabs.com>
Reviewed-by: Nick Lewis <nick@puppetlabs.com>

1 files changed, 4 insertions, 3 deletions

diff --git a/lib/puppet/parser/ast/leaf.rb b/lib/puppet/parser/ast/leaf.rb
index 64a197492..3efb52f63 100644
--- a/lib/puppet/parser/ast/leaf.rb
+++ b/lib/puppet/parser/ast/leaf.rb
@@ -124,10 +124,11 @@ class Puppet::Parser::AST
     # not include syntactical constructs, like '$' and '{}').
     def evaluate(scope)
       parsewrap do
-        if (var = scope[@value, {:file => file, :line => line}]) == :undefined
-          var = :undef
+        if ! scope.include?(@value)
+          :undef
+        else
+          scope[@value, {:file => file, :line => line}]
         end
-        var
       end
     end