1 files changed, 26 insertions, 15 deletions
diff --git a/activemodel/lib/active_model/mass_assignment_security/sanitizer.rb b/activemodel/lib/active_model/mass_assignment_security/sanitizer.rb
index cfeb4aa7cd..44ce5a489d 100644
--- a/activemodel/lib/active_model/mass_assignment_security/sanitizer.rb
+++ b/activemodel/lib/active_model/mass_assignment_security/sanitizer.rb
@@ -2,20 +2,18 @@ module ActiveModel
   module MassAssignmentSecurity
     class Sanitizer
       # Returns all attributes not denied by the authorizer.
-      def sanitize(attributes, authorizer)
-        sanitized_attributes = attributes.reject { |key, value| authorizer.deny?(key) }
-        debug_protected_attribute_removal(attributes, sanitized_attributes)
+      def sanitize(klass, attributes, authorizer)
+        rejected = []
+        sanitized_attributes = attributes.reject do |key, value|
+          rejected << key if authorizer.deny?(key)
+        end
+        process_removed_attributes(klass, rejected) unless rejected.empty?
         sanitized_attributes
       end
 
     protected
 
-      def debug_protected_attribute_removal(attributes, sanitized_attributes)
-        removed_keys = attributes.keys - sanitized_attributes.keys
-        process_removed_attributes(removed_keys) if removed_keys.any?
-      end
-
-      def process_removed_attributes(attrs)
+      def process_removed_attributes(klass, attrs)
         raise NotImplementedError, "#process_removed_attributes(attrs) suppose to be overwritten"
       end
     end
@@ -34,8 +32,21 @@ module ActiveModel
         @target.respond_to?(:logger) && @target.logger
       end
 
-      def process_removed_attributes(attrs)
-        logger.warn "Can't mass-assign protected attributes: #{attrs.join(', ')}" if logger?
+      def backtrace
+        if defined? Rails
+          Rails.backtrace_cleaner.clean(caller)
+        else
+          caller
+        end
+      end
+
+      def process_removed_attributes(klass, attrs)
+        if logger?
+          logger.warn do
+            "WARNING: Can't mass-assign protected attributes for #{klass.name}: #{attrs.join(', ')}\n" +
+                backtrace.map { |trace| "\t#{trace}" }.join("\n")
+          end
+        end
       end
     end
 
@@ -44,9 +55,9 @@ module ActiveModel
         super()
       end
 
-      def process_removed_attributes(attrs)
+      def process_removed_attributes(klass, attrs)
         return if (attrs - insensitive_attributes).empty?
-        raise ActiveModel::MassAssignmentSecurity::Error.new(attrs)
+        raise ActiveModel::MassAssignmentSecurity::Error.new(klass, attrs)
       end
 
       def insensitive_attributes
@@ -55,8 +66,8 @@ module ActiveModel
     end
 
     class Error < StandardError
-      def initialize(attrs)
-        super("Can't mass-assign protected attributes: #{attrs.join(', ')}")
+      def initialize(klass, attrs)
+        super("Can't mass-assign protected attributes for #{klass.name}: #{attrs.join(', ')}")
       end
     end
   end