Functional\Tests\UniqueTest::testUnifyingByClosure PHP Method

    public function testUnifyingByClosure()
    {
        $fn = function ($value, $key, $collection) {
            return $key === 0 ? 'zero' : 'else';
        };
        $this->assertSame([0 => 'value1', 1 => 'value2'], unique($this->list, $fn));
        $this->assertSame([0 => 'value1', 1 => 'value2'], unique($this->listIterator, $fn));
        $fn = function ($value, $key, $collection) {
            return 0;
        };
        $this->assertSame(['k1' => 'val1'], unique($this->hash, $fn));
        $this->assertSame(['k1' => 'val1'], unique($this->hashIterator, $fn));
    }