diff --git a/src/Buffer.php b/src/Buffer.php index d4083c2..843c219 100644 --- a/src/Buffer.php +++ b/src/Buffer.php @@ -335,16 +335,11 @@ final class Buffer implements TabularData private function nthRow(int $nth, string $method): array { -1 < $nth || throw InvalidArgument::dueToInvalidRecordOffset($nth, $method); - if (null === ($first = $this->firstOffset())) { - return []; - } - $offset = $first + $nth; - if (!array_key_exists($offset, $this->rows)) { - return []; - } - - return $this->rows[$nth + $first]; + // $nth is a positional index (like ResultSet::nth), so it must be + // resolved against the record order rather than the row keys, which + // may contain gaps after records have been deleted. + return array_values($this->rows)[$nth] ?? []; } public function fetchColumn(int|string $index = 0): Iterator diff --git a/src/BufferTest.php b/src/BufferTest.php index e373f7e..8c19af1 100644 --- a/src/BufferTest.php +++ b/src/BufferTest.php @@ -285,6 +285,24 @@ final class BufferTest extends TestCase self::assertSame(['date' => '2025-02-08', 'temperature' => '3', 'place' => 'Berkeley'], $buffer->nth(0)); } + #[Test] + public function it_returns_records_by_positional_offset_after_a_middle_record_is_deleted(): void + { + $buffer = new Buffer(['id', 'name']); + $buffer->insert(['1', 'a'], ['2', 'b'], ['3', 'c'], ['4', 'd'], ['5', 'e']); + + // Delete the second record (id = 2), which leaves a gap in the row keys. + self::assertSame(1, $buffer->delete(fn (array $row): bool => $row['id'] === '2')); + self::assertSame(4, $buffer->recordCount()); + + // nth() is positional and must stay consistent with getRecords(). + self::assertSame(['id' => '1', 'name' => 'a'], $buffer->nth(0)); + self::assertSame(['id' => '3', 'name' => 'c'], $buffer->nth(1)); + self::assertSame(['id' => '4', 'name' => 'd'], $buffer->nth(2)); + self::assertSame(['id' => '5', 'name' => 'e'], $buffer->nth(3)); + self::assertSame([], $buffer->nth(4)); + } + #[Test] public function it_can_not_insert_invalid_records(): void {