public function testRemove() { $elements = [1, 'A' => 'a', 2, 'B' => 'b', 3]; $collection = new ArrayCollection($elements); $this->assertSame(1, $collection->remove(0)); unset($elements[0]); $this->assertSame(null, $collection->remove('non-existent')); unset($elements['non-existent']); $this->assertSame(2, $collection->remove(1)); unset($elements[1]); $this->assertSame('a', $collection->remove('A')); unset($elements['A']); $this->assertSame($elements, $collection->toArray()); }