Incorrect behavior of AddReturnDocblockForCommonObjectDenominatorRector

[Yoann-TYT]

Bug Report

Subject	Details
Rector version	last dev-main
Installed as	composer dependency

Minimal PHP Code Causing Issue

See https://getrector.com/demo/075301d9-2544-491b-8b8f-d6ccbfcffc4c

<?php

final class Project
{
    public function __construct(
        public string $title
    ) {}
}

final class ProjectRepository
{
    /**
     * @return array<int, Project>
     */
    public function findRecent(): array
    {
        return [
            new Project('recent-1'),
            new Project('recent-2'),
        ];
    }
}

final class ProjectService
{
    public function __construct(private ProjectRepository $repo) {}

    public function getProjectsFromRepo(): array
    {
        return $this->repo->findRecent();
    }

    public function getProjectsInline(): array
    {
        return [
            new Project('inline-1'),
            new Project('inline-2'),
        ];
    }
}

Responsible rules

• AddReturnDocblockForCommonObjectDenominatorRector

Expected Behavior

Rector correctly adds the docblock for the getProjectsInline method, but not for the getProjectsFromRepo one. In short, it cannot generate it recursively. Do you think this case is too complex to handle, or could it be supported in the future?

Thanks a lot for your amazing work on Rector !

[TomasVotruba]

Thanks for reporting 👍

This is expected, as the rule only handles types that are inside the method body. Based on real native code.

We don't copy-paste existing docblocks from another method (even if called locally), as those can be wrong in the first place.
It would require extreemely complex nested reflection to detect such cases, so for now we skip them.