Rule to enforce that certain controller methods must "used"

[dereuromark]

Had to fix CS too.. also fixed some phpstan deprecations.

Summary

Implements a new PHPStan rule that enforces explicit return statements for controller methods like render() and redirect() to prevent
unreachable code and make control flow more explicit.

Fixes #49

Motivation

In CakePHP controllers, methods like render() and redirect() terminate the response and prevent further code execution. However, without
an explicit return statement, it's not immediately obvious that subsequent code is unreachable, which can lead to:

• Confusion about code execution flow
• Wasted time debugging code that never runs
• Maintenance issues when developers add code after these methods

Examples

Before (Problems Detected)

class ArticlesController extends Controller
{
    public function view($id)
    {
        $article = $this->Articles->get($id);

        if (!$article->published) {
            $this->redirect(['action' => 'index']);
            // This code is unreachable but not obvious!
            $this->Flash->error('Article not found');
        }

        $this->set(compact('article'));
    }

    public function edit($id)
    {
        // ...

        if ($this->request->is('ajax')) {
            $this->render('ajax_form');
            // Unreachable code that might confuse developers
            $this->set('debug', true);
        }
    }
}

PHPStan Output:

  ------ ---------------------------------------------------------------------------------------------
  Line   ArticlesController.php
  ------ ---------------------------------------------------------------------------------------------
  8      Method redirect() must be returned to prevent unreachable code.
         Use "return $this->redirect()" instead.
  18     Method render() must be returned to prevent unreachable code.
         Use "return $this->render()" instead.
  ------ ---------------------------------------------------------------------------------------------

After (Correct Usage)

  class ArticlesController extends Controller
  {
      public function view($id)
      {
          $article = $this->Articles->get($id);

          if (!$article->published) {
              // Explicit return makes it clear execution stops here
              return $this->redirect(['action' => 'index']);
          }

          $this->set(compact('article'));
      }

      public function edit($id)
      {
          // ...

          if ($this->request->is('ajax')) {
              // Clear that this terminates the action
              return $this->render('ajax_form');
          }

          // Regular flow continues here
          $this->set('title', 'Edit Article');
      }
  }

Implementation Details

• Rule Location: src/Rule/Controller/ControllerMethodMustReturnRule.php
• Detected Methods: render(), redirect()
• Detection: Analyzes AST Expression nodes to find method calls that aren't wrapped in return statements
• Scope: Only applies to classes that extend Cake\Controller\Controller
• Default State: Enabled by default

Configuration

The rule is enabled by default. To disable it:

  # phpstan.neon
  parameters:
      cakeDC:
          controllerMethodMustReturnRule: false