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
74 def after_save
75   super
76   reset_initial_values
77 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
81 def after_update
82   super
83   @previous_changes = column_changes
84 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
91 def column_change(column)
92   [initial_value(column), get_column_value(column)] if column_changed?(column)
93 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
113 def column_changed?(column)
114   initial_values.has_key?(column)
115 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
 99 def column_changes
100   h = {}
101   initial_values.each do |column, value|
102     h[column] = [value, get_column_value(column)]
103   end
104   h
105 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
128 def column_previously_changed?(column, opts=OPTS)
129   return false unless (pc = @previous_changes) && (val = pc[column])
130 
131   if opts.has_key?(:from)
132     return false unless val[0] == opts[:from]
133   end
134 
135   if opts.has_key?(:to)
136     return false unless val[1] == opts[:to]
137   end
138 
139   true
140 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
148 def column_previously_was(column)
149   (pc = @previous_changes) && (val = pc[column]) && val[0]
150 end
freeze()

Freeze internal data structures

[show source] 
    # File lib/sequel/plugins/dirty.rb
153 def freeze
154   initial_values.freeze
155   missing_initial_values.freeze
156   @previous_changes.freeze if @previous_changes
157   super
158 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
165 def initial_value(column)
166   initial_values.fetch(column){get_column_value(column)}
167 end
initial_values()

A hash with column symbol keys and initial values.

initial_values # {:name => 'Initial'}
[show source] 
    # File lib/sequel/plugins/dirty.rb
172 def initial_values
173   @initial_values ||= {}
174 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
181 def reset_column(column)
182   if initial_values.has_key?(column)
183     set_column_value(:"#{column}=", initial_values[column])
184   end
185   if missing_initial_values.include?(column)
186     values.delete(column)
187   end
188 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
196 def will_change_column(column)
197   _add_changed_column(column)
198   check_missing_initial_value(column)
199 
200   value = if initial_values.has_key?(column)
201     initial_values[column]
202   else
203     get_column_value(column)
204   end
205 
206   initial_values[column] = if value && value != true && value.respond_to?(:clone)
207     begin
208       value.clone
209     rescue TypeError
210       value
211     end
212   else
213     value
214   end
215 end