Syntax errors when using assert_equal with the suggested syntax in minitest v4.3.3

minitest-assert_equal.rb

require 'minitest/autorun'

class HashEquality

  attr_reader :options

  def initialize(opts={})
    @options = opts
  end

end


class HashEqualityTest < MiniTest::Unit::TestCase

  def test_options_is_empty
    hash_equality = HashEquality.new

    # no problem here, just demonstrating I'm not stupid.
    assert_empty hash_equality.options, "options must be empty when not given any arguments"
  end

  def test_options_with_arguments_is_not_empty
    hash_equality = HashEquality.new(:foo => 'bar')

    # no problem here, just demonstrating I'm not stupid.
    refute_empty hash_equality.options, "options must not be empty when given arguments"
  end


  # assert_equal is written as assert_equal(expected, actual, message)...

  def test_options_with_no_args_is_equal_to_empty_hash_literal
    hash_equality = HashEquality.new

    # raises 'syntax error, unexpected ',', expecting keyword_end' after hash literal
    assert_equal {}, hash_equality.options, "options should be the same as an empty hash literal"
  end

  def test_options_with_no_args_is_equal_to_empty_hash_literal_reversed
    hash_equality = HashEquality.new

    # works
    assert_equal hash_equality.options, {}, "options should be the same as an empty hash literal"
  end

  def test_options_with_args_is_equal_to_hash_literal_with_values
    hash_equality = HashEquality.new(:foo => 'bar')

    # raises 'syntax error, unexpected ',', expecting keyword_end' after hash literal
    assert_equal {:foo => 'bar'}, hash_equality.options, "options should be the same as hash literal with values"
  end

  def test_options_with_args_is_equal_to_hash_literal_with_values_reversed
    hash_equality = HashEquality.new(:foo => 'bar')

    # works
    assert_equal hash_equality.options, {:foo => 'bar'}, "options should be the same as hash literal with values"
  end

  def test_options_with_no_args_same_as_new_hash
    hash_equality = HashEquality.new

    # works.
    assert_equal Hash.new, hash_equality.options, "options should be equal to a Hash.new object"
  end

  def test_options_with_args_same_as_new_hash_with_args
    hash_equality = HashEquality.new(:foo => 'bar')

    # works.
    assert_equal Hash[:foo, 'bar'], hash_equality.options, "options should be equal to a Hash.new object with args"
  end

end