@function test-partial-1($a, $b) {
  @return ($a, $b);
}
@function test-partial-2($args...) {
  @return length($args);
}
@include test-module('_partial methods') {
  @each $method-name in 'partial', 'partial-right' {
    $func: unquote('_#{$method-name}');
    $is-partial: $method-name == 'partial';

    $par: _call($func, null, _identity, 'a');

    @include test('#{$func} partially applies arguments') {
      @include assert-equal(_call($par), 'a');
    }

    $expected: ('a', 'b');
    $par: _call($func, null, test-partial-1, 'a');

    @include test('#{$func} creates a function that can be invoked with additional arguments') {
      @include assert-true(test-lists-equal(_call($par, null, 'b'), if($is-partial, $expected, __list-reverse($expected))));
    }

    $par: _call($func, null, test-partial-2);

    @include test('#{$func} works when there are no partially applied arguments and the created function is invoked without additional arguments') {
      @include assert-equal(_call($par), 0);
    }

    $par: _call($func, null, _identity);

    @include test('#{$func} works when there are no partially applied arguments and the created function is invoked with additional arguments') {
      @include assert-equal(_call($par, null, 'a'), 'a');
    }
  }
}