1 files changed, 37 insertions, 0 deletions
diff --git a/lib/strip_attributes/strip_attributes.rb b/lib/strip_attributes/strip_attributes.rb
new file mode 100644
index 000000000..130d10185
--- /dev/null
+++ b/lib/strip_attributes/strip_attributes.rb
@@ -0,0 +1,37 @@
+module StripAttributes
+  # Strips whitespace from model fields and leaves nil values as nil.
+  # XXX this differs from official StripAttributes, as it doesn't make blank cells null.
+  def strip_attributes!(options = nil)
+    before_validation do |record|
+      attribute_names = StripAttributes.narrow(record.attribute_names, options)
+
+      attribute_names.each do |attribute_name|
+        value = record[attribute_name]
+        if value.respond_to?(:strip)
+          stripped = value.strip
+          if stripped != value
+            record[attribute_name] = (value.nil?) ? nil : stripped
+          end
+        end
+      end
+    end
+  end
+
+  # Necessary because Rails has removed the narrowing of attributes using :only
+  # and :except on Base#attributes
+  def self.narrow(attribute_names, options)
+    if options.nil?
+      attribute_names
+    else
+      if except = options[:except]
+        except = Array(except).collect { |attribute| attribute.to_s }
+        attribute_names - except
+      elsif only = options[:only]
+        only = Array(only).collect { |attribute| attribute.to_s }
+        attribute_names & only
+      else
+        raise ArgumentError, "Options does not specify :except or :only (#{options.keys.inspect})"
+      end
+    end
+  end
+end