Fix handling of custom Expr objects

extension.neon

@@ -170,3 +170,10 @@ services:
 		arguments:
 			class: Doctrine\ORM\Query\Expr\OrderBy
 			argumentsProcessor: @doctrineQueryBuilderArgumentsProcessor
+	-
+		class: PHPStan\Type\Doctrine\QueryBuilder\Expr\NewExprDynamicReturnTypeExtension
+		tags:
+			- phpstan.broker.dynamicStaticMethodReturnTypeExtension
+		arguments:
+			class: Doctrine\ORM\Query\Expr
+			argumentsProcessor: @doctrineQueryBuilderArgumentsProcessor

phpstan.neon

@@ -16,7 +16,7 @@ parameters:
 			message: '~^Variable method call on Doctrine\\ORM\\QueryBuilder~'
 			path: */src/Type/Doctrine/QueryBuilder/QueryBuilderGetQueryDynamicReturnTypeExtension.php
 		-
-			message: '~^Variable method call on Doctrine\\ORM\\Query\\Expr\.$~'
+			message: '~^Variable method call on object\.$~'
 			path: */src/Type/Doctrine/QueryBuilder/Expr/ExpressionBuilderDynamicReturnTypeExtension.php
 		-
 			message: '~^Variable property access on PhpParser\\Node\\Stmt\\Declare_\|PhpParser\\Node\\Stmt\\Namespace_\.$~'

src/Type/Doctrine/QueryBuilder/Expr/ExpressionBuilderDynamicReturnTypeExtension.php

@@ -64,7 +64,18 @@ public function getTypeFromMethodCall(MethodReflection $methodReflection, Method
 			return $defaultReturnType;
 		}
 
-		$exprValue = $queryBuilder->expr()->{$methodReflection->getName()}(...$args);
+		$calledOnType = $scope->getType($methodCall->var);
+		if ($calledOnType instanceof ExprType) {
+			$expr = $calledOnType->getExprObject();
+		} else {
+			$expr = $queryBuilder->expr();
+		}
+
+		if (!method_exists($expr, $methodReflection->getName())) {
+			return $defaultReturnType;
+		}
+
+		$exprValue = $expr->{$methodReflection->getName()}(...$args);
 		if (is_object($exprValue)) {
 			return new ExprType(get_class($exprValue), $exprValue);
 		}

tests/Rules/Doctrine/ORM/QueryBuilderDqlRuleTest.php

@@ -2,6 +2,7 @@
 
 namespace PHPStan\Rules\Doctrine\ORM;
 
+use Doctrine\ORM\Query\Expr;
 use Doctrine\ORM\Query\Expr\Base;
 use Doctrine\ORM\Query\Expr\OrderBy;
 use PHPStan\DependencyInjection\Container;
@@ -102,6 +103,10 @@ public function testRule(): void
 				'QueryBuilder: [Semantical Error] line 0, col 60 near \'nonexistent =\': Error: Class PHPStan\Rules\Doctrine\ORM\MyEntity has no field or association named nonexistent',
 				251,
 			],
+			[
+				"QueryBuilder: [Syntax Error] line 0, col -1: Error: Expected =, <, <=, <>, >, >=, !=, got end of string.\nDQL: SELECT e FROM PHPStan\Rules\Doctrine\ORM\MyEntity e WHERE foo",
+				281,
+			],
 		]);
 	}
 
@@ -210,6 +215,7 @@ public function getDynamicStaticMethodReturnTypeExtensions(): array
 		return [
 			new NewExprDynamicReturnTypeExtension($argumentsProcessor, OrderBy::class),
 			new NewExprDynamicReturnTypeExtension($argumentsProcessor, Base::class),
+			new NewExprDynamicReturnTypeExtension($argumentsProcessor, Expr::class),
 		];
 	}
 

tests/Rules/Doctrine/ORM/data/query-builder-dql.php

@@ -261,4 +261,44 @@ public function anotherWeirdTypeSpecifyingExtensionProblem(): void
 		$queryBuilder->getQuery();
 	}
 
+	public function qbCustomExprMethod(): void
+	{
+		$expr = new CustomExpr();
+		$queryBuilder = $this->entityManager->createQueryBuilder();
+		$queryBuilder->select('e')
+			->from(MyEntity::class, 'e')
+			->andWhere($expr->correct());
+		$queryBuilder->getQuery();
+	}
+
+	public function qbCustomExprMethodSyntaxError(): void
+	{
+		$expr = new CustomExpr();
+		$queryBuilder = $this->entityManager->createQueryBuilder();
+		$queryBuilder->select('e')
+			->from(MyEntity::class, 'e')
+			->andWhere($expr->syntaxError());
+		$queryBuilder->getQuery();
+	}
+
+}
+
+class CustomExpr extends \Doctrine\ORM\Query\Expr
+{
+
+	public function __construct()
+	{
+		// necessary so that NewExprDynamicReturnTypeExtension works
+	}
+
+	public function syntaxError(): string
+	{
+		return 'foo';
+	}
+
+	public function correct(): string
+	{
+		return 'e.id = 1';
+	}
+
 }