1 files changed, 18 insertions, 2 deletions
diff --git a/lib/puppet/parser/functions/has_interface_with.rb b/lib/puppet/parser/functions/has_interface_with.rb
index 927b0df..3691524 100644
--- a/lib/puppet/parser/functions/has_interface_with.rb
+++ b/lib/puppet/parser/functions/has_interface_with.rb
@@ -35,13 +35,29 @@ has_interface_with("lo")                        => true
 
     kind, value = args
 
-    if lookupvar(kind) == value
+    # Bug with 3.7.1 - 3.7.3  when using future parser throws :undefined_variable
+    # https://tickets.puppetlabs.com/browse/PUP-3597
+    factval = nil
+    catch :undefined_variable do
+      factval = lookupvar(kind)
+    end
+    if factval == value
       return true
     end
 
     result = false
     interfaces.each do |iface|
-      if value == lookupvar("#{kind}_#{iface}")
+      iface.downcase!
+      factval = nil
+      begin
+        # Bug with 3.7.1 - 3.7.3 when using future parser throws :undefined_variable
+        # https://tickets.puppetlabs.com/browse/PUP-3597
+        catch :undefined_variable do
+          factval = lookupvar("#{kind}_#{iface}")
+        end
+      rescue Puppet::ParseError # Eat the exception if strict_variables = true is set
+      end
+      if value == factval
         result = true
         break
       end