refactor: use dedicated class to handle currency

[18alantom]

Changes

Currency handling using pesa

• frappe.pesa to be used to handle money related quantities.
• frappe.pesa is initialized with SystemSettings#internalPrecision and AccountingSettings#currency.

frappe.db.getSingleValues

await frappe.db.getSingleValues('currency', 'internalPrecision')

await frappe.db.getSingleValues(
  {fieldname: 'currency', parent: 'AccountingSettings'},
  {fieldname: 'internalPrecision', parent: 'SystemSettings'}
)

// Both will return:
// [ 
//    {fieldname: 'internalPrecision', value: '11', parent: 'SystemSettings'},
//    {fieldname: 'currency', value: 'INR', parent: 'AccountingSettings'}
// ]

Number Formatting

Hash based number formats have been removed. Intl.NumberFormat will be used instead. This is locale dependent, each country has an associated locale from which the number format is obtained.

• frappe.formatNumber(value) makes use of Intl.NumberFormat on the passed value. Valid values are:
  • string like numbers
  • pesa objects
  • numbers
• frappe.formatCurrency(value, currency) uses the above function and prepends the currency sigil obtained from the currency code having the format "XXX". Intl.NumberFormat was not used in currency mode here cause the sigil used to not always load.

Frappe Books: https://github.com/frappe/books/pull/268