Fix phpstan/phpstan#14443: bisect command

bin/phpstan

@@ -2,6 +2,7 @@
 <?php declare(strict_types=1);
 
 use PHPStan\Command\AnalyseCommand;
+use PHPStan\Command\BisectCommand;
 use PHPStan\Command\ClearResultCacheCommand;
 use PHPStan\Command\DiagnoseCommand;
 use PHPStan\Command\DumpParametersCommand;
@@ -129,6 +130,7 @@ use Symfony\Component\Console\Helper\ProgressBar;
 	$reversedComposerAutoloaderProjectPaths = array_values(array_unique(array_reverse($composerAutoloaderProjectPaths)));
 
 	$application->add(new AnalyseCommand($reversedComposerAutoloaderProjectPaths, $analysisStartTime));
+	$application->add(new BisectCommand());
 	$application->add(new WorkerCommand($reversedComposerAutoloaderProjectPaths));
 	$application->add(new ClearResultCacheCommand($reversedComposerAutoloaderProjectPaths));
 	$application->add(new FixerWorkerCommand($reversedComposerAutoloaderProjectPaths));

src/Command/Bisect/BinarySearch.php

@@ -0,0 +1,36 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Command\Bisect;
+
+use InvalidArgumentException;
+use function array_slice;
+use function ceil;
+use function count;
+use function log;
+
+final class BinarySearch
+{
+
+	/**
+	 * @template T
+	 * @param list<T> $items Items ordered from oldest to newest (at least 2)
+	 * @return BinarySearchStep<T>
+	 */
+	public static function getStep(array $items): BinarySearchStep
+	{
+		$count = count($items);
+		if ($count < 2) {
+			throw new InvalidArgumentException('Binary search requires at least 2 items.');
+		}
+
+		$mid = (int) (($count - 1) / 2);
+
+		return new BinarySearchStep(
+			$items[$mid],
+			array_slice($items, $mid + 1),
+			array_slice($items, 0, $mid + 1),
+			(int) ceil(log($count, 2)),
+		);
+	}
+
+}

src/Command/Bisect/BinarySearchStep.php

@@ -0,0 +1,25 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Command\Bisect;
+
+/**
+ * @template T
+ */
+final class BinarySearchStep
+{
+
+	/**
+	 * @param T $item Item to test
+	 * @param list<T> $ifGood Remaining items to search if this item is good
+	 * @param list<T> $ifBad Remaining items to search if this item is bad
+	 */
+	public function __construct(
+		public readonly mixed $item,
+		public readonly array $ifGood,
+		public readonly array $ifBad,
+		public readonly int $stepsRemaining,
+	)
+	{
+	}
+
+}