public function testThatDifferenceWithDuplicateKeysPreservesTheOriginalValues(\Pinq\ITraversable $traversable, array $data) { $otherData = [0 => 'test', 2 => 0.01, 5 => 4, 'test' => 1]; $intersection = $traversable->difference($otherData); $this->assertMatches($intersection, array_diff($data, $otherData)); }