From 4064b5e76e455f80321cd0c7d0c8704a6061d2ab Mon Sep 17 00:00:00 2001
From: Johannes Meyer <johannes.meyer@icinga.com>
Date: Wed, 5 Aug 2026 11:35:46 +0200
Subject: [PATCH] Query: Fix some phpstan errors related to generics

* Query::setModel() now implicitly changes the type of the query
* Query::createSubQuery() returns a proper typed result
* Query::derive() properly signals it does not know the result's type
---
 src/Query.php     | 17 ++++++++++++-----
 src/ResultSet.php |  1 +
 2 files changed, 13 insertions(+), 5 deletions(-)

diff --git a/src/Query.php b/src/Query.php
index b2af92c..d08b18f 100644
--- a/src/Query.php
+++ b/src/Query.php
@@ -158,7 +158,10 @@ public function getModel()
     /**
      * Set the model to query
      *
-     * @param TRow $model
+     * @template TNew of Model
+     * @phpstan-self-out static<TNew>
+     *
+     * @param TNew $model
      *
      * @return $this
      */
@@ -577,7 +580,7 @@ public function createHydrator(): Hydrator
      * @param string $relation
      * @param TRow $source
      *
-     * @return static
+     * @return static<*>
      *
      * @throws InvalidArgumentException If the relation with the given name does not exist
      */
@@ -594,12 +597,14 @@ public function derive($relation, Model $source): static
     /**
      * Create a sub-query linked to rows of this query
      *
-     * @param Model $target The model to query
+     * @template TTarget of Model
+     *
+     * @param TTarget $target The model to query
      * @param string $targetPath The target's absolute relation path
      * @param ?TRow $from The source model
      * @param bool $link Whether the query should be linked to the parent query
      *
-     * @return static
+     * @return static<TTarget>
      */
     public function createSubQuery(Model $target, string $targetPath, ?Model $from = null, bool $link = true): static
     {
@@ -617,9 +622,11 @@ public function createSubQuery(Model $target, string $targetPath, ?Model $from =
         $subQuery->utilize($sourcePath); // TODO: Don't join if there's a matching foreign key
 
         if (! $link) {
-            return $subQuery->columns(array_map(function ($keyName) use ($sourcePath) {
+            $subQuery->columns(array_map(function ($keyName) use ($sourcePath) {
                 return "$sourcePath.$keyName";
             }, (array) $subQueryTarget->getKeyName()));
+
+            return $subQuery;
         }
 
         // TODO: Should be done by the caller. Though, that's not possible until we've got a filter abstraction
diff --git a/src/ResultSet.php b/src/ResultSet.php
index 3ca7160..55d581f 100644
--- a/src/ResultSet.php
+++ b/src/ResultSet.php
@@ -46,6 +46,7 @@ public function __construct(Traversable $traversable, ?int $limit = null)
      * Create a new result set from the given query
      *
      * @template TQueryRow of Model
+     *
      * @param Query<TQueryRow> $query
      *
      * @return static<TQueryRow>