fix: collection template types being overwritten

Author: calebdw

src/Support/CollectionHelper.php

@@ -86,8 +86,10 @@ public function determineCollectionClassName(string $modelClassName): string
         }
     }
 
-    public function determineCollectionClass(string $modelClassName): Type
+    public function determineCollectionClass(string $modelClassName, Type|null $modelType = null): Type
     {
+        $modelType ??= new ObjectType($modelClassName);
+
         $collectionClassName  = $this->determineCollectionClassName($modelClassName);
         $collectionReflection = $this->reflectionProvider->getClass($collectionClassName);
 
@@ -96,12 +98,12 @@ public function determineCollectionClass(string $modelClassName): Type
 
             // Specifies key and value
             if ($typeMap->count() === 2) {
-                return new GenericObjectType($collectionClassName, [new IntegerType(), new ObjectType($modelClassName)]);
+                return new GenericObjectType($collectionClassName, [new IntegerType(), $modelType]);
             }
 
             // Specifies only value
             if (($typeMap->count() === 1) && $typeMap->hasType('TModel')) {
-                return new GenericObjectType($collectionClassName, [new ObjectType($modelClassName)]);
+                return new GenericObjectType($collectionClassName, [$modelType]);
             }
         }
 
@@ -124,13 +126,14 @@ public function replaceCollectionsInType(Type $type): Type
                 return $traverse($type);
             }
 
-            $models = $type->getTemplateType(EloquentCollection::class, 'TModel')->getObjectClassNames();
-
-            if (count($models) === 0) {
-                return $type;
-            }
+            $templateType = $type->getTemplateType(EloquentCollection::class, 'TModel');
+            $models       = $templateType->getObjectClassNames();
 
-            return TypeCombinator::union(...array_map([$this, 'determineCollectionClass'], $models));
+            return match (count($models)) {
+                0 => $type,
+                1 => $this->determineCollectionClass($models[0], $templateType),
+                default => TypeCombinator::union(...array_map(fn ($m) => $this->determineCollectionClass($m), $models)),
+            };
         });
     }
 

tests/Type/GeneralTypeTest.php

@@ -23,6 +23,7 @@ public static function dataFileAsserts(): iterable
         yield from self::gatherAssertTypes(__DIR__ . '/data/bug-1565.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/bug-1760.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/bug-1830.php');
+        yield from self::gatherAssertTypes(__DIR__ . '/data/bug-2044.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/carbon.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/conditionable.php');
         yield from self::gatherAssertTypes(__DIR__ . '/data/container-array-access.php');

tests/Type/data/bug-2044.php

@@ -0,0 +1,24 @@
+<?php
+
+namespace Bug2044;
+
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Collection;
+
+use function PHPStan\Testing\assertType;
+
+/** @template TModel of \Illuminate\Database\Eloquent\Model */
+class Repository
+{
+    /** @var Builder<TModel> */
+    private Builder $query;
+
+    /** @return Collection<int, TModel> */
+    public function all(): Collection
+    {
+        $models = $this->query->get();
+        assertType('Illuminate\Database\Eloquent\Collection<int, TModel of Illuminate\Database\Eloquent\Model (class Bug2044\Repository, argument)>', $models);
+
+        return $models;
+    }
+}