Formatting

Rails-less formatting for your unit-testable code.

Does currently depend on the i18n library for number separators.

Very much a work in progress currently.

Formats:

  • Numbers
  • Currency

Usage

Call methods on Formatting:

Formatting.format_number(1234.567)  # => "1,234.57"

Or include the modules you want:

include Formatting::Number
format_number(1234)  # => "1,234"

include Formatting::Currency
format_currency("SEK", 1234)  # => "1,234 SEK"

Number

Example usage

Formatting.format_number(1234.567)  # => "1,234.57"
Formatting.format_number(0, blank_when_zero: true)  # => ""
Formatting.format_number(1, explicit_sign: true)  # => "+1"

Options

name default explanation
thousands_separator I18n.t("number.format.delimiter") if available, otherwise a non-breaking space
decimal_separator I18n.t("number.format.separator") if available, otherwise "."
round 2 Round to the given number of decimals. Don't round if given false.
blank_when_zero false If true, returns "" for a zero value.
min_decimals 2 Show at least that number of decimals. Don't enforce if given false.
explicit_sign false If true, prefixes positive values with a "+". Doesn't prefix 0.

Currency

The currency formatter should usually be passed some object that the currency can be determined from. The idea is that even if you only have one currency now, you may add more later.

Example usage

item = Item.new(price: 1234, currency: "SEK")
Formatting.format_currency(item, :price)  # => "1,234.00 SEK"
Formatting.format_currency(company, item.price)  # => "1,234.00 SEK"
Formatting.format_currency(company, 4567)  # => "4,567.00 SEK"

Formatting.format_currency(company, 4567, currency: false)  # => "4,567.00"

Options

Passes on all the number options and also takes these:

name default explanation
currency first_argument.currency if available E.g. "USD". Can be false.
format "<amount> <currency>" A format string. Any spaces become non-breaking spaces.
skip_currency false If true, doesn't add the currency to the amount.

Installation

Add this line to your application's Gemfile:

gem 'formatting'

And then execute:

$ bundle

Or install it yourself as:

$ gem install formatting

TODO

  • Use real i18n in specs so they're less fragile and ugly
  • Document options
  • Rename? This name is boring and also generic enough that collisions seem likely.