📣 New Gem! rspec-dry-types

Speed up test-driven development with looser or stronger type-checking in your RSpec tests

The rspec-dry-types gem is a drop-in replacement for RSpec's be_a_kind_of() that allows you to TIGHTEN or LOOSEN what object types you expect returned.

Powered by the dry-types gem, you can find a list of all the reference keys for supported types dry-types documentation for "Built-in Types".

USAGE:

require 'dry-types'
require 'rspec/expectations'
require 'rspec/matchers/be_of_type'

RSpec.describe "check types using be_of_type" do
  include RSpec::Matchers::DryTypes

  it 'can use a symbol to expect a dry-type' do
    expect('a string').to be_of_type(:string)
    expect(123).to be_of_type(:integer)
    expect(0.123).to be_of_type(:float)
    expect("123").to be_of_type(:integer, strict: false)
    expect(nil).to be_of_type(:string, strict: false)
    expect(nil).to be_of_type(:nil)
  end

  # Strings must reference the dry-types docs
  it 'can use string to expect a dry-type' do
    expect('a string').to be_of_type('string')
    expect('a string').to be_of_type('strict.string')
    expect(123).to be_of_type('integer')
    expect(123).to be_of_type('strict.integer')
    expect(0.123).to be_of_type('float')
    expect(0.123).to be_of_type('coercible.integer')
    expect("123").to be_of_type('integer', strict: false)
    expect(nil).to be_of_type('string', strict: false)
    expect(nil).to be_of_type('nil')
  end

  # Strings must reference the dry-types docs
  it 'is backwards compat with be_a' do
    expect('a string').to be_a(String)
    expect('a string').to be_a_kind_of('strict.string')
    expect(123).to be_an(Integer)
    expect(123).to be_an('integer')
  end

  it 'can use a class to check if its a type' do
    # Check inheritance
    expect(String).to be_of_type(Object)
    expect('a string').to be_of_type(Object)
    expect(123).to be_of_type(Object)

    # Check coercion
    expect(123).to be_of_type(String, strict: false)
    expect(0.123).not_to be_of_type(Integer)
    expect(0.123).to be_of_type(Integer, strict: false)
  end

end