Add Twitter::Error::UnprocessableEntity

README.md

@@ -136,10 +136,11 @@ removed.
 
 ### Errors
 
-It's worth mentioning two new error classes:
+It's worth mentioning new error classes:
 
 * `Twitter::Error::GatewayTimeout`
 * `Twitter::Error::RateLimited`
+* `Twitter::Error::UnprocessableEntity`
 
 In previous versions of this library, rate limit errors were indicated by
 raising either `Twitter::Error::BadRequest` or

lib/twitter/error/unprocessable_entity.rb

@@ -0,0 +1,10 @@
+require 'twitter/error/client_error'
+
+module Twitter
+  class Error
+    # Raised when Twitter returns the HTTP status code 404
+    class UnprocessableEntity < Twitter::Error::ClientError
+      HTTP_STATUS_CODE = 422
+    end
+  end
+end

lib/twitter/response/raise_error.rb

@@ -9,6 +9,7 @@
 require 'twitter/error/rate_limited'
 require 'twitter/error/service_unavailable'
 require 'twitter/error/unauthorized'
+require 'twitter/error/unprocessable_entity'
 
 module Twitter
   module Response