Merge pull request getsentry#625 from miyachik/fix-format-message

Fix format message if params is empty

Close getsentry#624

Author: nateberkopec

lib/raven/interfaces/message.rb

@@ -10,7 +10,7 @@ def initialize(*arguments)
     end
 
     def unformatted_message
-      params.nil? ? message : message % params
+      Array(params).empty? ? message : message % params
     end
 
     def self.sentry_alias

spec/raven/interface_spec.rb

@@ -30,4 +30,8 @@ class TestInterface < Raven::Interface
     interface = Raven::MessageInterface.new(:params => nil, :message => "test '%'")
     expect(interface.unformatted_message).to eq("test '%'")
   end
+  it "supports invalid format string message when params is empty" do
+    interface = Raven::MessageInterface.new(:message => "test '%'")
+    expect(interface.unformatted_message).to eq("test '%'")
+  end
 end