fix: keep original type in collect function in some cases

src/ReturnTypes/Helpers/CollectExtension.php

@@ -38,7 +38,7 @@ public function getTypeFromFunctionCall(
         FunctionReflection $functionReflection,
         FuncCall $functionCall,
         Scope $scope
-    ): Type {
+    ): ?Type {
         if (count($functionCall->getArgs()) < 1) {
             return new GenericObjectType(Collection::class, [new BenevolentUnionType([new IntegerType(), new StringType()]), new MixedType()]);
         }

src/Support/CollectionHelper.php

@@ -9,23 +9,20 @@
 use Illuminate\Support\Enumerable;
 use Iterator;
 use IteratorAggregate;
-use PHPStan\Type\GeneralizePrecision;
+use PHPStan\Type\BenevolentUnionType;
 use PHPStan\Type\Generic\GenericObjectType;
 use PHPStan\Type\IntegerType;
 use PHPStan\Type\MixedType;
 use PHPStan\Type\ObjectType;
 use PHPStan\Type\StringType;
 use PHPStan\Type\Type;
-use PHPStan\Type\TypeCombinator;
 use PHPStan\Type\TypeWithClassName;
 use Traversable;
 
 final class CollectionHelper
 {
-    public function determineGenericCollectionTypeFromType(Type $type): GenericObjectType
+    public function determineGenericCollectionTypeFromType(Type $type): ?GenericObjectType
     {
-        $keyType = TypeCombinator::union(new IntegerType(), new StringType());
-
         if ($type instanceof TypeWithClassName) {
             if ((new ObjectType(Enumerable::class))->isSuperTypeOf($type)->yes()) {
                 return $this->getTypeFromEloquentCollection($type);
@@ -45,23 +42,20 @@ public function determineGenericCollectionTypeFromType(Type $type): GenericObjec
         }
 
         if ($type->isIterableAtLeastOnce()->no()) {
-            return new GenericObjectType(Collection::class, [$keyType, new MixedType()]);
+            return new GenericObjectType(Collection::class, [new BenevolentUnionType([new IntegerType(), new StringType()]), new MixedType()]);
         }
 
-        return new GenericObjectType(Collection::class, [
-            $type->getIterableKeyType()->generalize(GeneralizePrecision::lessSpecific()),
-            $type->getIterableValueType()->generalize(GeneralizePrecision::lessSpecific()),
-        ]);
+        return null;
     }
 
-    private function getTypeFromEloquentCollection(TypeWithClassName $valueType): GenericObjectType
+    private function getTypeFromEloquentCollection(TypeWithClassName $valueType): ?GenericObjectType
     {
-        $keyType = TypeCombinator::union(new IntegerType(), new StringType());
+        $keyType = new BenevolentUnionType([new IntegerType(), new StringType()]);
 
         $classReflection = $valueType->getClassReflection();
 
         if ($classReflection === null) {
-            return new GenericObjectType(Collection::class, [$keyType, new MixedType()]);
+            return null;
         }
 
         $innerValueType = $classReflection->getActiveTemplateTypeMap()->getType('TModel');
@@ -74,17 +68,17 @@ private function getTypeFromEloquentCollection(TypeWithClassName $valueType): Ge
             return new GenericObjectType(Collection::class, [$keyType, $innerValueType]);
         }
 
-        return new GenericObjectType(Collection::class, [$keyType, new MixedType()]);
+        return null;
     }
 
-    private function getTypeFromIterator(TypeWithClassName $valueType): GenericObjectType
+    private function getTypeFromIterator(TypeWithClassName $valueType): ?GenericObjectType
     {
-        $keyType = TypeCombinator::union(new IntegerType(), new StringType());
+        $keyType = new BenevolentUnionType([new IntegerType(), new StringType()]);
 
         $classReflection = $valueType->getClassReflection();
 
         if ($classReflection === null) {
-            return new GenericObjectType(Collection::class, [$keyType, new MixedType()]);
+            return null;
         }
 
         $templateTypes = array_values($classReflection->getActiveTemplateTypeMap()->getTypes());

tests/Type/data/collection-generic-static-methods.php

@@ -174,7 +174,7 @@
     })
 );
 
-assertType('Illuminate\Support\Collection<(int|string), Illuminate\Support\Collection<(int|string), non-empty-array<string, int|string>>>', collect([
+assertType('Illuminate\Support\Collection<(int|string), Illuminate\Support\Collection<(int|string), array{id: int, type: string}>>', collect([
     [
         'id'   => 1,
         'type' => 'A',

tests/Type/data/collection-helper.php

@@ -12,13 +12,15 @@
 assertType('Illuminate\Support\Collection<0, \'foo\'>', collect('foo'));
 assertType('Illuminate\Support\Collection<0, 3.14>', collect(3.14));
 assertType('Illuminate\Support\Collection<0, true>', collect(true));
-assertType('Illuminate\Support\Collection<int|string, mixed>', collect([]));
+assertType('Illuminate\Support\Collection<(int|string), mixed>', collect([]));
 assertType('Illuminate\Support\Collection<int, int>', collect([1, 2, 3]));
 assertType('Illuminate\Support\Collection<int, string>', collect(['foo', 'bar', 'baz']));
 assertType('Illuminate\Support\Collection<int, float>', collect([1.0, 2.0, 3.0]));
 assertType('Illuminate\Support\Collection<int, float|int|string>', collect([1, 'foo', 1.0]));
-assertType("Illuminate\Support\Collection<int, non-empty-array<int, string>>", collect([['a', 'b', 'c']]));
-assertType("Illuminate\Support\Collection<int, non-empty-array<int, string>>", collect([['a', 'b', 'c']])->push(array_fill(0, 3, 'x')));
+assertType("Illuminate\Support\Collection<int, array{string, string, string}>", collect([['a', 'b', 'c']]));
+assertType("Illuminate\Support\Collection<int, array{string, string, string}>", collect([['a', 'b', 'c']])->push(array_fill(0, 3, 'x')));
+assertType("Illuminate\Support\Collection<int, App\User>", collect([new User, new User]));
+assertType("Illuminate\Support\Collection<int, array{App\User, App\User, App\User}>", collect([[new User, new User, new User]]));
 
 /**  @phpstan-param EloquentCollection<int, int> $eloquentCollection */
 function eloquentCollectionInteger(EloquentCollection $eloquentCollection): void