Return list<mixed> from PDOStatement::fetchAll() (#5643)

phpstan-bot · VincentLanglet · claude · web-flow · commit 86f8b7aa2a50 · 2026-05-15T15:53:56.000+02:00
Co-authored-by: Vincent Langlet &lt;vincentlanglet@hotmail.fr&gt;
Co-authored-by: Claude Opus 4.6 &lt;noreply@anthropic.com&gt;
Co-authored-by: Vincent Langlet &lt;VincentLanglet@users.noreply.github.com&gt;
diff --git a/src/Type/Php/PdoStatementFetchAllReturnTypeExtension.php b/src/Type/Php/PdoStatementFetchAllReturnTypeExtension.php
@@ -0,0 +1,80 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\Type\Php;
+
+use PDO;
+use PhpParser\Node\Expr\MethodCall;
+use PHPStan\Analyser\Scope;
+use PHPStan\DependencyInjection\AutowiredService;
+use PHPStan\Reflection\MethodReflection;
+use PHPStan\Reflection\ParametersAcceptorSelector;
+use PHPStan\Type\Accessory\AccessoryArrayListType;
+use PHPStan\Type\ArrayType;
+use PHPStan\Type\Constant\ConstantBooleanType;
+use PHPStan\Type\DynamicMethodReturnTypeExtension;
+use PHPStan\Type\IntegerType;
+use PHPStan\Type\MixedType;
+use PHPStan\Type\Type;
+use PHPStan\Type\TypeCombinator;
+use PHPStan\Type\TypeUtils;
+use function count;
+
+#[AutowiredService]
+final class PdoStatementFetchAllReturnTypeExtension implements DynamicMethodReturnTypeExtension
+{
+
+	public function getClass(): string
+	{
+		return 'PDOStatement';
+	}
+
+	public function isMethodSupported(MethodReflection $methodReflection): bool
+	{
+		return $methodReflection->getName() === 'fetchAll';
+	}
+
+	public function getTypeFromMethodCall(
+		MethodReflection $methodReflection,
+		MethodCall $methodCall,
+		Scope $scope,
+	): ?Type
+	{
+		$args = $methodCall->getArgs();
+		if (count($args) < 1) {
+			return null;
+		}
+
+		$modeType = $scope->getType($args[0]->value);
+		$constantIntegers = TypeUtils::getConstantIntegers($modeType);
+
+		if (count($constantIntegers) === 0) {
+			return null;
+		}
+
+		foreach ($constantIntegers as $constantInteger) {
+			$mode = $constantInteger->getValue();
+			if (
+				($mode & 0xFFFF) === PDO::FETCH_KEY_PAIR
+				|| ($mode & PDO::FETCH_GROUP) !== 0
+				|| ($mode & PDO::FETCH_UNIQUE) !== 0
+			) {
+				return null;
+			}
+		}
+
+		$variant = ParametersAcceptorSelector::selectFromArgs($scope, $args, $methodReflection->getVariants());
+		$returnType = $variant->getReturnType();
+
+		$listType = TypeCombinator::intersect(
+			new ArrayType(new IntegerType(), new MixedType()),
+			new AccessoryArrayListType(),
+		);
+
+		if (!$returnType->isFalse()->no()) {
+			return TypeCombinator::union($listType, new ConstantBooleanType(false));
+		}
+
+		return $listType;
+	}
+
+}
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11889-php7.php b/tests/PHPStan/Analyser/nsrt/bug-11889-php7.php
@@ -0,0 +1,18 @@
+<?php // lint < 8.0
+
+declare(strict_types = 1);
+
+namespace Bug11889Php7;
+
+use PDO;
+use PDOStatement;
+use function PHPStan\Testing\assertType;
+
+function test(PDOStatement $stmt): void
+{
+	assertType('list|false', $stmt->fetchAll(PDO::FETCH_ASSOC));
+	assertType('list|false', $stmt->fetchAll(PDO::FETCH_COLUMN));
+
+	// Non-list modes
+	assertType('array|false', $stmt->fetchAll(PDO::FETCH_KEY_PAIR));
+}
diff --git a/tests/PHPStan/Analyser/nsrt/bug-11889.php b/tests/PHPStan/Analyser/nsrt/bug-11889.php
@@ -0,0 +1,49 @@
+<?php // lint >= 8.0
+
+declare(strict_types = 1);
+
+namespace Bug11889;
+
+use PDO;
+use PDOStatement;
+use function PHPStan\Testing\assertType;
+
+function test(PDOStatement $stmt): void
+{
+	// No mode argument - unknown default, stays as array
+	assertType('array', $stmt->fetchAll());
+
+	// Single-argument modes that return lists
+	assertType('list', $stmt->fetchAll(PDO::FETCH_ASSOC));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_NUM));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_BOTH));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_OBJ));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_COLUMN));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_CLASS));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_NAMED));
+
+	// Modes that return non-list arrays
+	assertType('array', $stmt->fetchAll(PDO::FETCH_KEY_PAIR));
+	assertType('array', $stmt->fetchAll(PDO::FETCH_GROUP | PDO::FETCH_ASSOC));
+	assertType('array', $stmt->fetchAll(PDO::FETCH_UNIQUE | PDO::FETCH_ASSOC));
+
+	// Multi-argument overload variants always return lists
+	assertType('list', $stmt->fetchAll(PDO::FETCH_COLUMN, 0));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_CLASS, \stdClass::class));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_CLASS, \stdClass::class, []));
+	assertType('list', $stmt->fetchAll(PDO::FETCH_FUNC, function () {
+		return 'test';
+	}));
+}
+
+/**
+ * @return list<string>
+ */
+function get_cv_files(): array
+{
+	$pdo = new PDO("");
+	$stmt = $pdo->prepare('SELECT `file` FROM `commonvoice`');
+	$stmt->execute();
+
+	return $stmt->fetchAll(PDO::FETCH_COLUMN);
+}
