chore: Add rector ruleset to avoid invalid database queries

build/rector-query-limit.php

@@ -0,0 +1,35 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+use Nextcloud\Rector\Rector\RemoveSetMaxResultsFromJoinQueryRector;
+use Rector\Config\RectorConfig;
+
+require_once __DIR__ . '/rector/RemoveSetMaxResultsFromJoinQueryRector.php';
+
+$nextcloudDir = dirname(__DIR__);
+
+return RectorConfig::configure()
+	->withPaths([
+		$nextcloudDir . '/apps',
+		$nextcloudDir . '/core',
+		$nextcloudDir . '/lib',
+		$nextcloudDir . '/ocs',
+	])
+	->withSkip([
+		$nextcloudDir . '/apps/*/3rdparty/*',
+		$nextcloudDir . '/apps/*/vendor/*',
+		$nextcloudDir . '/lib/public/*',
+	])
+	->withRules([
+		RemoveSetMaxResultsFromJoinQueryRector::class,
+	]);
+
+
+
+

build/rector/RemoveSetMaxResultsFromJoinQueryRector.php

@@ -0,0 +1,113 @@
+<?php
+
+declare(strict_types=1);
+
+/**
+ * SPDX-FileCopyrightText: 2026 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+namespace Nextcloud\Rector\Rector;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\MethodCall;
+use Rector\Rector\AbstractRector;
+use Symplify\RuleDocGenerator\ValueObject\CodeSample\CodeSample;
+use Symplify\RuleDocGenerator\ValueObject\RuleDefinition;
+
+/**
+ * Removes `->setMaxResults()` and `->setFirstResult()` from IQueryBuilder chains
+ * that contain an innerJoin or leftJoin.
+ *
+ * Using LIMIT and OFFSET on a JOIN query against partitioned tables causes:
+ *   "Limit is not allowed in partitioned queries"
+ *
+ * These methods must be removed when joins are present to maintain
+ * cross-database compatibility (MySQL, PostgreSQL, SQLite).
+ */
+final class RemoveSetMaxResultsFromJoinQueryRector extends AbstractRector {
+
+	private const JOIN_METHODS = ['innerJoin', 'leftJoin'];
+	private const LIMIT_METHODS = ['setMaxResults', 'setFirstResult'];
+
+	public function getRuleDefinition(): RuleDefinition {
+		return new RuleDefinition(
+			'Remove setMaxResults() and setFirstResult() from IQueryBuilder chains with innerJoin/leftJoin to avoid "Limit is not allowed in partitioned queries"',
+			[
+				new CodeSample(
+					<<<'CODE_BEFORE'
+$query = $builder->select('id')
+    ->from('mounts', 'm')
+    ->innerJoin('m', 'filecache', 'f', $builder->expr()->eq('m.root_id', 'f.fileid'))
+    ->where($builder->expr()->eq('user_id', $builder->createNamedParameter($uid)))
+    ->setMaxResults(1)
+    ->setFirstResult(0);
+CODE_BEFORE
+					,
+					<<<'CODE_AFTER'
+$query = $builder->select('id')
+    ->from('mounts', 'm')
+    ->innerJoin('m', 'filecache', 'f', $builder->expr()->eq('m.root_id', 'f.fileid'))
+    ->where($builder->expr()->eq('user_id', $builder->createNamedParameter($uid)));
+CODE_AFTER
+				),
+			]
+		);
+	}
+
+	/**
+	 * @return array<class-string<Node>>
+	 */
+	public function getNodeTypes(): array {
+		return [MethodCall::class];
+	}
+
+	/**
+	 * @param MethodCall $node
+	 */
+	public function refactor(Node $node): ?Node {
+		if (!($node instanceof MethodCall)) {
+			return null;
+		}
+
+		// Only flag setMaxResults() or setFirstResult() calls
+		$isLimitMethod = false;
+		foreach (self::LIMIT_METHODS as $method) {
+			if ($this->isName($node->name, $method)) {
+				$isLimitMethod = true;
+				break;
+			}
+		}
+
+		if (!$isLimitMethod) {
+			return null;
+		}
+
+		// Walk the fluent chain on the receiver side to find innerJoin or leftJoin
+		if (!$this->chainContainsJoin($node->var)) {
+			return null;
+		}
+
+		// Replace `$chain->setMaxResults(...)->setFirstResult(...)` with just `$chain`.
+		return $node->var;
+	}
+
+	private function chainContainsJoin(Expr $expr): bool {
+		if (!($expr instanceof MethodCall)) {
+			return false;
+		}
+		foreach (self::JOIN_METHODS as $joinMethod) {
+			if ($this->isName($expr->name, $joinMethod)) {
+				// Verify the join has a condition (4th parameter)
+				// innerJoin($fromAlias, $join, $alias, $condition, ...)
+				$args = $expr->getArgs();
+				if (count($args) >= 4) {
+					return true;
+				}
+			}
+		}
+		return $this->chainContainsJoin($expr->var);
+	}
+}
+