app/cyclid/monkey_patches.rb in cyclid-0.2.5 vs app/cyclid/monkey_patches.rb in cyclid-0.3.0

@@ -7,31 +7,58 @@
       hash.merge(yield(k, v))
     end
   end
 
   # Interpolate the data in the ctx hash into any String values
-  def interpolate(ctx)
+  def %(other)
     hmap do |key, value|
       if value.is_a? String
-        { key => value % ctx }
+        { key => value ** other }
       else
         { key => value }
       end
     end
   end
 end
 
 # Add a method to Array
 class Array
   # Interpolate the data in the ctx hash for each String & Hash item
-  def interpolate(ctx)
+  def %(other)
     map do |entry|
       if entry.is_a? Hash
-        entry.interpolate ctx
+        entry % other
       elsif entry.is_a? String
-        entry % @ctx
+        entry ** other
       else
         entry
       end
     end
+  end
+end
+
+# Add a method to String
+class String
+  # Provide a "safe" version of the % (interpolation) operator; if a key does
+  # not exist in arg, catch the KeyError and insert it as a nil value, and
+  # continue.
+  #
+  # We're using the ** operator as it's one that isn't already used by String,
+  # and it's abusing % already so hey, why not. FTP
+  def **(other)
+    res = nil
+    arg = other ? other.dup : {}
+
+    begin
+      res = self % arg
+    rescue KeyError => ex
+      # Extract the key name from the exception message (sigh)
+      match = ex.message.match(/\Akey{(.*)} not found\Z/)
+      key = match[1]
+
+      # Inject key with a default value and try again
+      arg[key.to_sym] = nil
+    end while res.nil? # rubocop:disable Lint/Loop
+
+    return res
   end
 end