1 files changed, 12 insertions, 10 deletions
diff --git a/lib/expand_variables.rb b/lib/expand_variables.rb
index 40bf9483eb5..669735cc56c 100644
--- a/lib/expand_variables.rb
+++ b/lib/expand_variables.rb
@@ -1,15 +1,17 @@
-String.instance_eval
-  def expand_variables(variables)
-    # Convert hash array to variables
-    if variables.is_a?(Array)
-      variables = variables.reduce({}) do |hash, variable|
-        hash[variable[:key]] = variable[:value]
-        hash
+module ExpandVariables
+  class << self
+    def expand_variables(value, variables)
+      # Convert hash array to variables
+      if variables.is_a?(Array)
+        variables = variables.reduce({}) do |hash, variable|
+          hash[variable[:key]] = variable[:value]
+          hash
+        end
       end
-    end
 
-    self.gsub(/\$([a-zA-Z_][a-zA-Z0-9_]*)|\${\g<1>}|%\g<1>%/) do
-      variables[$1 || $2]
+      value.gsub(/\$([a-zA-Z_][a-zA-Z0-9_]*)|\${\g<1>}|%\g<1>%/) do
+        variables[$1 || $2]
+      end
     end
   end
 end