module Sequel::Plugins::Dirty::InstanceMethods

  1. lib/sequel/plugins/dirty.rb

Attributes

previous_changes [R]

A hash of previous changes before the object was saved, in the same format as column_changes. Note that this is not necessarily the same as the columns that were used in the update statement.

Public Instance methods

after_save()

Reset the initial values after saving.

[show source] 
   # File lib/sequel/plugins/dirty.rb
78 def after_save
79   super
80   reset_initial_values
81 end
after_update()

Save the current changes so they are available after updating. This happens before after_save resets them.

[show source] 
   # File lib/sequel/plugins/dirty.rb
85 def after_update
86   super
87   @previous_changes = column_changes
88 end
column_change(column)

An array with the initial value and the current value of the column, if the column has been changed. If the column has not been changed, returns nil.

column_change(:name) # => ['Initial', 'Current']
[show source] 
   # File lib/sequel/plugins/dirty.rb
95 def column_change(column)
96   [initial_value(column), get_column_value(column)] if column_changed?(column)
97 end
column_changed?(column)

Either true or false depending on whether the column has changed. Note that this is not exactly the same as checking if the column is in changed_columns, if the column was not set initially.

column_changed?(:name) # => true
[show source] 
    # File lib/sequel/plugins/dirty.rb
117 def column_changed?(column)
118   initial_values.has_key?(column)
119 end
column_changes()

A hash with column symbol keys and pairs of initial and current values for all changed columns.

column_changes # => {:name => ['Initial', 'Current']}
[show source] 
    # File lib/sequel/plugins/dirty.rb
103 def column_changes
104   h = {}
105   initial_values.each do |column, value|
106     h[column] = [value, get_column_value(column)]
107   end
108   h
109 end
column_previously_changed?(column, opts=OPTS)

Whether the column was previously changed. Options:

:from

If given, the previous initial value of the column must match this

:to

If given, the previous changed value of the column must match this

update(name: 'Current')
previous_changes                  # => {:name=>['Initial', 'Current']}
column_previously_changed?(:name) # => true
column_previously_changed?(:id)   # => false
column_previously_changed?(:name, from: 'Initial', to: 'Current') # => true
column_previously_changed?(:name, from: 'Foo', to: 'Current')     # => false
[show source] 
    # File lib/sequel/plugins/dirty.rb
132 def column_previously_changed?(column, opts=OPTS)
133   return false unless (pc = @previous_changes) && (val = pc[column])
134 
135   if opts.has_key?(:from)
136     return false unless val[0] == opts[:from]
137   end
138 
139   if opts.has_key?(:to)
140     return false unless val[1] == opts[:to]
141   end
142 
143   true
144 end
column_previously_was(column)

The previous value of the column, which is the initial value of the column before the object was previously saved.

initial_value(:name) # => 'Initial'
update(name: 'Current')
column_previously_was(:name) # => 'Initial'
[show source] 
    # File lib/sequel/plugins/dirty.rb
152 def column_previously_was(column)
153   (pc = @previous_changes) && (val = pc[column]) && val[0]
154 end
freeze()

Freeze internal data structures

[show source] 
    # File lib/sequel/plugins/dirty.rb
157 def freeze
158   initial_values.freeze
159   missing_initial_values.freeze
160   @previous_changes.freeze if @previous_changes
161   super
162 end
initial_value(column)

The initial value of the given column. If the column value has not changed, this will be the same as the current value of the column.

initial_value(:name) # => 'Initial'
[show source] 
    # File lib/sequel/plugins/dirty.rb
169 def initial_value(column)
170   initial_values.fetch(column){get_column_value(column)}
171 end
initial_values()

A hash with column symbol keys and initial values.

initial_values # {:name => 'Initial'}
[show source] 
    # File lib/sequel/plugins/dirty.rb
176 def initial_values
177   @initial_values ||= {}
178 end
reset_column(column)

Reset the column to its initial value. If the column was not set initial, removes it from the values.

reset_column(:name)
name # => 'Initial'
[show source] 
    # File lib/sequel/plugins/dirty.rb
185 def reset_column(column)
186   if initial_values.has_key?(column)
187     set_column_value(:"#{column}=", initial_values[column])
188   end
189   if missing_initial_values.include?(column)
190     values.delete(column)
191   end
192 end
will_change_column(column)

Manually specify that a column will change. This should only be used if you plan to modify a column value in place, which is not recommended.

will_change_column(:name)
name.gsub(/i/i, 'o')
column_change(:name) # => ['Initial', 'onotoal']
[show source] 
    # File lib/sequel/plugins/dirty.rb
200 def will_change_column(column)
201   _add_changed_column(column)
202   check_missing_initial_value(column)
203 
204   value = if initial_values.has_key?(column)
205     initial_values[column]
206   else
207     get_column_value(column)
208   end
209 
210   initial_values[column] = if value && value != true && value.respond_to?(:clone)
211     begin
212       value.clone
213     rescue TypeError
214       value
215     end
216   else
217     value
218   end
219 end