# frozen_string_literal: true
require "abstract_unit"
require "active_support/core_ext/array"
require "active_support/core_ext/enumerable"
Payment = Struct.new(:price)
ExpandedPayment = Struct.new(:dollars, :cents)
class SummablePayment < Payment
def +(p) self.class.new(price + p.price) end
end
class EnumerableTests < ActiveSupport::TestCase
class GenericEnumerable
include Enumerable
def initialize(values = [1, 2, 3])
@values = values
end
def each
@values.each { |v| yield v }
end
end
def assert_typed_equal(e, v, cls, msg = nil)
assert_kind_of(cls, v, msg)
assert_equal(e, v, msg)
end
def test_sums
enum = GenericEnumerable.new([5, 15, 10])
assert_equal 30, enum.sum
assert_equal 60, enum.sum { |i| i * 2 }
enum = GenericEnumerable.new(%w(a b c))
assert_equal "abc", enum.sum
assert_equal "aabbcc", enum.sum { |i| i * 2 }
payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
assert_equal 30, payments.sum(&:price)
assert_equal 60, payments.sum { |p| p.price * 2 }
payments = GenericEnumerable.new([ SummablePayment.new(5), SummablePayment.new(15) ])
assert_equal SummablePayment.new(20), payments.sum
assert_equal SummablePayment.new(20), payments.sum { |p| p }
sum = GenericEnumerable.new([3, 5.quo(1)]).sum
assert_typed_equal(8, sum, Rational)
sum = GenericEnumerable.new([3, 5.quo(1)]).sum(0.0)
assert_typed_equal(8.0, sum, Float)
sum = GenericEnumerable.new([3, 5.quo(1), 7.0]).sum
assert_typed_equal(15.0, sum, Float)
sum = GenericEnumerable.new([3, 5.quo(1), Complex(7)]).sum
assert_typed_equal(Complex(15), sum, Complex)
assert_typed_equal(15, sum.real, Rational)
assert_typed_equal(0, sum.imag, Integer)
sum = GenericEnumerable.new([3.5, 5]).sum
assert_typed_equal(8.5, sum, Float)
sum = GenericEnumerable.new([2, 8.5]).sum
assert_typed_equal(10.5, sum, Float)
sum = GenericEnumerable.new([1.quo(2), 1]).sum
assert_typed_equal(3.quo(2), sum, Rational)
sum = GenericEnumerable.new([1.quo(2), 1.quo(3)]).sum
assert_typed_equal(5.quo(6), sum, Rational)
sum = GenericEnumerable.new([2.0, 3.0 * Complex::I]).sum
assert_typed_equal(Complex(2.0, 3.0), sum, Complex)
assert_typed_equal(2.0, sum.real, Float)
assert_typed_equal(3.0, sum.imag, Float)
sum = GenericEnumerable.new([1, 2]).sum(10) { |v| v * 2 }
assert_typed_equal(16, sum, Integer)
end
def test_nil_sums
expected_raise = TypeError
assert_raise(expected_raise) { GenericEnumerable.new([5, 15, nil]).sum }
payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10), Payment.new(nil) ])
assert_raise(expected_raise) { payments.sum(&:price) }
assert_equal 60, payments.sum { |p| p.price.to_i * 2 }
end
def test_empty_sums
assert_equal 0, GenericEnumerable.new([]).sum
assert_equal 0, GenericEnumerable.new([]).sum { |i| i + 10 }
assert_equal Payment.new(0), GenericEnumerable.new([]).sum(Payment.new(0))
assert_typed_equal 0.0, GenericEnumerable.new([]).sum(0.0), Float
end
def test_range_sums
assert_equal 20, (1..4).sum { |i| i * 2 }
assert_equal 10, (1..4).sum
assert_equal 10, (1..4.5).sum
assert_equal 6, (1...4).sum
assert_equal "abc", ("a".."c").sum
assert_equal 50_000_005_000_000, (0..10_000_000).sum
assert_equal 0, (10..0).sum
assert_equal 5, (10..0).sum(5)
assert_equal 10, (10..10).sum
assert_equal 42, (10...10).sum(42)
assert_typed_equal 20.0, (1..4).sum(0.0) { |i| i * 2 }, Float
assert_typed_equal 10.0, (1..4).sum(0.0), Float
assert_typed_equal 20.0, (1..4).sum(10.0), Float
assert_typed_equal 5.0, (10..0).sum(5.0), Float
end
def test_array_sums
enum = [5, 15, 10]
assert_equal 30, enum.sum
assert_equal 60, enum.sum { |i| i * 2 }
enum = %w(a b c)
assert_equal "abc", enum.sum
assert_equal "aabbcc", enum.sum { |i| i * 2 }
payments = [ Payment.new(5), Payment.new(15), Payment.new(10) ]
assert_equal 30, payments.sum(&:price)
assert_equal 60, payments.sum { |p| p.price * 2 }
payments = [ SummablePayment.new(5), SummablePayment.new(15) ]
assert_equal SummablePayment.new(20), payments.sum
assert_equal SummablePayment.new(20), payments.sum { |p| p }
sum = [3, 5.quo(1)].sum
assert_typed_equal(8, sum, Rational)
sum = [3, 5.quo(1)].sum(0.0)
assert_typed_equal(8.0, sum, Float)
sum = [3, 5.quo(1), 7.0].sum
assert_typed_equal(15.0, sum, Float)
sum = [3, 5.quo(1), Complex(7)].sum
assert_typed_equal(Complex(15), sum, Complex)
assert_typed_equal(15, sum.real, Rational)
assert_typed_equal(0, sum.imag, Integer)
sum = [3.5, 5].sum
assert_typed_equal(8.5, sum, Float)
sum = [2, 8.5].sum
assert_typed_equal(10.5, sum, Float)
sum = [1.quo(2), 1].sum
assert_typed_equal(3.quo(2), sum, Rational)
sum = [1.quo(2), 1.quo(3)].sum
assert_typed_equal(5.quo(6), sum, Rational)
sum = [2.0, 3.0 * Complex::I].sum
assert_typed_equal(Complex(2.0, 3.0), sum, Complex)
assert_typed_equal(2.0, sum.real, Float)
assert_typed_equal(3.0, sum.imag, Float)
sum = [1, 2].sum(10) { |v| v * 2 }
assert_typed_equal(16, sum, Integer)
end
def test_index_by
payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
payments.index_by(&:price))
assert_equal Enumerator, payments.index_by.class
assert_nil payments.index_by.size
assert_equal 42, (1..42).index_by.size
assert_equal({ 5 => Payment.new(5), 15 => Payment.new(15), 10 => Payment.new(10) },
payments.index_by.each(&:price))
end
def test_index_with
payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
assert_equal({ Payment.new(5) => 5, Payment.new(15) => 15, Payment.new(10) => 10 }, payments.index_with(&:price))
assert_equal({ title: nil, body: nil }, %i( title body ).index_with(nil))
assert_equal({ title: [], body: [] }, %i( title body ).index_with([]))
assert_equal({ title: {}, body: {} }, %i( title body ).index_with({}))
assert_equal Enumerator, payments.index_with.class
assert_nil payments.index_with.size
assert_equal 42, (1..42).index_with.size
assert_equal({ Payment.new(5) => 5, Payment.new(15) => 15, Payment.new(10) => 10 }, payments.index_with.each(&:price))
end
def test_many
assert_equal false, GenericEnumerable.new([]).many?
assert_equal false, GenericEnumerable.new([ 1 ]).many?
assert_equal true, GenericEnumerable.new([ 1, 2 ]).many?
assert_equal false, GenericEnumerable.new([]).many? { |x| x > 1 }
assert_equal false, GenericEnumerable.new([ 2 ]).many? { |x| x > 1 }
assert_equal false, GenericEnumerable.new([ 1, 2 ]).many? { |x| x > 1 }
assert_equal true, GenericEnumerable.new([ 1, 2, 2 ]).many? { |x| x > 1 }
end
def test_many_iterates_only_on_what_is_needed
infinity = 1.0 / 0.0
very_long_enum = 0..infinity
assert_equal true, very_long_enum.many?
assert_equal true, very_long_enum.many? { |x| x > 100 }
end
def test_exclude?
assert_equal true, GenericEnumerable.new([ 1 ]).exclude?(2)
assert_equal false, GenericEnumerable.new([ 1 ]).exclude?(1)
end
def test_excluding
assert_equal [1, 2, 4], GenericEnumerable.new((1..5).to_a).excluding(3, 5)
assert_equal [3, 4, 5], GenericEnumerable.new((1..5).to_a).excluding([1, 2])
assert_equal [[0, 1]], GenericEnumerable.new([[0, 1], [1, 0]]).excluding([[1, 0]])
assert_equal [1, 2, 4], (1..5).to_a.excluding(3, 5)
assert_equal [1, 2, 4], (1..5).to_set.excluding(3, 5)
assert_equal({ foo: 1, baz: 3 }, { foo: 1, bar: 2, baz: 3 }.excluding(:bar))
end
def test_without
assert_equal [1, 2, 4], GenericEnumerable.new((1..5).to_a).without(3, 5)
assert_equal [3, 4, 5], GenericEnumerable.new((1..5).to_a).without([1, 2])
end
def test_pluck
payments = GenericEnumerable.new([ Payment.new(5), Payment.new(15), Payment.new(10) ])
assert_equal [5, 15, 10], payments.pluck(:price)
payments = GenericEnumerable.new([
ExpandedPayment.new(5, 99),
ExpandedPayment.new(15, 0),
ExpandedPayment.new(10, 50)
])
assert_equal [[5, 99], [15, 0], [10, 50]], payments.pluck(:dollars, :cents)
end
end
