Class: Timeprice::Point

Inherits:
Data
  • Object
show all
Defined in:
lib/timeprice/point.rb

Overview

A (currency, date) pair used as input to compare.

The library accepts either a Point or a 2-element array. Arrays may be ordered either way (‘[“USD”, “2010”]` or `[“2010”, “USD”]`) — the year and currency are detected by shape. This mirrors what the CLI already tolerates and removes the only “which slot is which?” footgun.

Examples:

Timeprice::Point.new(currency: "USD", date: "2010")
Timeprice::Point.coerce(["USD", "2010"])
Timeprice::Point.coerce(["2010", "USD"])

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Attribute Details

#currency ⇒ Object (readonly)

Returns the value of attribute currency

Returns:

  • (Object) —

    the current value of currency



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# File 'lib/timeprice/point.rb', line 15

def currency
  @currency
end

#date ⇒ Object (readonly)

Returns the value of attribute date

Returns:

  • (Object) —

    the current value of date



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# File 'lib/timeprice/point.rb', line 15

def date
  @date
end

Class Method Details

.coerce(input) ⇒ Point

Coerce input into a Point. Accepts:

- {Point} (returned as-is)
- 2-element Array of [currency, date] in either order

Parameters:

Returns:

Raises:

  • (ArgumentError) —

    if shape can’t be recognised



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# File 'lib/timeprice/point.rb', line 23

def self.coerce(input)
  return input if input.is_a?(Point)

  unless input.is_a?(Array) && input.size == 2
    raise ArgumentError, "Expected Timeprice::Point or [currency, date] tuple, got #{input.inspect}"
  end

  a, b = input.map(&:to_s)
  currency = [a, b].find { |s| s.match?(/\A[A-Za-z]{3}\z/) }
  date     = [a, b].find { |s| s.match?(/\A\d{4}(-\d{2}(-\d{2})?)?\z/) }

  if currency.nil? || date.nil?
    raise ArgumentError,
          "Could not detect currency + date in #{input.inspect} " \
          "(expected a 3-letter currency and a YYYY[-MM[-DD]] date)"
  end

  new(currency: currency.upcase, date: date)
end