Account Tax Change

This module adds a way to prepare tax changes and apply them to existing invoices.

• Under the Accounting menu you get a new "Tax changes" screen. There you create a tax change with a name, a date and a company, and add mapping lines that say which tax should be replaced by which other tax. From and To taxes must be of the same tax type, and the same name/company/date combination cannot be saved twice.

• On invoices you get an "Apply tax changes" action (available to billing users). It opens a small window where you pick a tax change and the invoices to update. Only draft, unpaid invoices can be selected; posted, paid or cancelled invoices are refused with an error message.

• When you validate, the module looks at each invoice line, and if it carries one of the "From" taxes it removes it and adds the corresponding "To" tax. A warning in the window states that once validated the change cannot be rolled back.

• The module touches account.tax.change, account.tax.change.line, account.move.apply.tax.change and account.move. Only accounting managers can create, edit or delete tax changes; other accounting users can only read them.