public function testConcat() { $this->coll->add(1)->add(2)->add(4); $coll2 = new ArrayList([3]); $this->coll->concat($coll2); $this->assertEquals([1, 2, 4, 3], $this->coll->toArray()); $coll3 = new Dictionary(['key1' => 'value1', 'key2' => 'wrongValue']); $coll4 = new Dictionary(['key2' => 'value2']); $coll3->concat($coll4); $this->assertEquals(['key1' => 'value1', 'key2' => 'value2'], $coll3->toArray()); }