Sort the results of PriorityQueue::toArray() according to priority

Closes laminas#21

Signed-off-by: George Steel <[email protected]>

src/PriorityQueue.php

@@ -17,6 +17,7 @@
 use function serialize;
 use function sprintf;
 use function unserialize;
+use function usort;
 
 /**
  * Re-usable, serializable priority queue implementation
@@ -245,13 +246,12 @@ public function __unserialize(array $data): void
  }
 
  /**
- * Serialize to an array
- * By default, returns only the item data, and in the order registered (not
- * sorted). You may provide one of the EXTR_* flags as an argument, allowing
+ * Serialize to an array, ordered by priority
+ * By default, returns only the item data. You may provide one of the EXTR_* flags as an argument, allowing
  * the ability to return priorities or both data and priority.
  *
  * @param self::EXTR_* $flag
- * @return array<array-key, mixed>
+ * @return list<mixed>
  * @psalm-return ($flag is self::EXTR_BOTH
  * ? list<array{data: TValue, priority: int}>
  * : $flag is self::EXTR_PRIORITY
@@ -261,10 +261,19 @@ public function __unserialize(array $data): void
  */
  public function toArray(int $flag = self::EXTR_DATA): array
  {
+ /**
+ * A manual sort is required because $item['priority'] as stored in the inner queue could be an array as
+ * opposed to an integer.
+ */
+ $items = $this->items;
+ usort($items, function (array $a, array $b): int {
+ return $b['priority'] <=> $a['priority'];
+ });
+
  return match ($flag) {
- self::EXTR_BOTH => $this->items,
- self::EXTR_PRIORITY => array_map(static fn($item): int => $item['priority'], $this->items),
- default => array_map(static fn($item): mixed => $item['data'], $this->items),
+ self::EXTR_BOTH => $items,
+ self::EXTR_PRIORITY => array_map(static fn($item): int => $item['priority'], $items),
+ default => array_map(static fn($item): mixed => $item['data'], $items),
  };
  }
 

test/PriorityQueueTest.php

@@ -56,8 +56,8 @@ public function testSerializationAndDeserializationShouldMaintainState(): void
  public function testRetrievingQueueAsArrayReturnsDataOnlyByDefault(): void
  {
  $expected = [
- 'foo',
  'bar',
+ 'foo',
  'baz',
  'bat',
  ];
@@ -68,8 +68,8 @@ public function testRetrievingQueueAsArrayReturnsDataOnlyByDefault(): void
  public function testCanCastToArrayOfPrioritiesOnly(): void
  {
  $expected = [
- 3,
  4,
+ 3,
  2,
  1,
  ];
@@ -80,8 +80,8 @@ public function testCanCastToArrayOfPrioritiesOnly(): void
  public function testCanCastToArrayOfDataPriorityPairs(): void
  {
  $expected = [
- ['data' => 'foo', 'priority' => 3],
  ['data' => 'bar', 'priority' => 4],
+ ['data' => 'foo', 'priority' => 3],
  ['data' => 'baz', 'priority' => 2],
  ['data' => 'bat', 'priority' => 1],
  ];