Raised by save! and create! when the record is invalid. Use the record method to retrieve the record which did not validate. 

  begin
    complex_operation_that_calls_save!_internally
  rescue ActiveRecord::RecordInvalid => invalid
    puts invalid.record.errors
  end
Methods
N
Attributes
[R] record
Class Public methods
new(record)

Source: show | on GitHub 

    # File activerecord/lib/active_record/validations.rb, line 11
11:     def initialize(record)
12:       @record = record
13:       errors = @record.errors.full_messages.join(I18n.t('support.array.words_connector', :default => ', '))
14:       super(I18n.t('activerecord.errors.messages.record_invalid', :errors => errors))
15:     end