Update deprecations panel to use new error handlers

Update deprecations panel to trap errors using the new events. Support
for the old error handler is being dropped as it was awkward and didn't
really work that well anymore.

Author: markstory

composer.json

@@ -24,7 +24,7 @@
     },
     "require": {
         "php": ">=7.2",
-        "cakephp/cakephp": "^4.3.0",
+        "cakephp/cakephp": "dev-4.next as 4.4.0",
         "cakephp/chronos": "^2.0",
         "composer/composer": "^1.3 | ^2.0",
         "jdorn/sql-formatter": "^1.2"
@@ -58,5 +58,10 @@
         "psalm": "psalm.phar --show-info=false",
         "psalm-setup": "cp composer.json composer.backup && composer require --dev psalm/phar:^4.10 && mv composer.backup composer.json"
     },
-    "prefer-stable": true
+    "prefer-stable": true,
+    "config": {
+        "allow-plugins": {
+            "dealerdirect/phpcodesniffer-composer-installer": true
+        }
+    }
 }

src/Panel/DeprecationsPanel.php

@@ -59,10 +59,6 @@ protected function _prepare()
         foreach ($errors as $error) {
             $file = $error['file'];
             $line = $error['line'];
-            if (isset($error['context']['frame'])) {
-                $file = $error['context']['frame']['file'];
-                $line = $error['context']['frame']['line'];
-            }
 
             $errorData = [
                 'file' => $file,

src/Plugin.php

@@ -19,6 +19,8 @@
 use Cake\Core\BasePlugin;
 use Cake\Core\Configure;
 use Cake\Core\PluginApplicationInterface;
+use Cake\Error\PhpError;
+use Cake\Event\EventInterface;
 use Cake\Event\EventManager;
 use Cake\Http\MiddlewareQueue;
 use DebugKit\Command\BenchmarkCommand;
@@ -50,7 +52,6 @@ public function bootstrap(PluginApplicationInterface $app): void
         }
 
         $this->service = $service;
-
         $this->setDeprecationHandler($service);
 
         // will load `config/bootstrap.php`.
@@ -92,40 +93,29 @@ public function console(CommandCollection $commands): CommandCollection
     public function setDeprecationHandler($service)
     {
         if (!empty($service->getConfig('panels')['DebugKit.Deprecations'])) {
-            $previousHandler = set_error_handler(
-                function ($code, $message, $file, $line, $context = null) use (&$previousHandler) {
-                    if ($code == E_USER_DEPRECATED || $code == E_DEPRECATED) {
-                        // In PHP 8.0+ the $context variable has been removed from the set_error_handler callback
-                        // Therefore we need to fetch the correct file and line string ourselves
-                        if (PHP_VERSION_ID >= 80000) {
-                            $trace = debug_backtrace();
-                            foreach ($trace as $idx => $traceEntry) {
-                                if ($traceEntry['function'] !== 'deprecationWarning') {
-                                    continue;
-                                }
-                                $offset = 1;
-                                // ['args'][1] refers to index of $stackFrame argument in deprecationWarning()
-                                if (isset($traceEntry['args'][1])) {
-                                    $offset = $traceEntry['args'][1];
-                                }
-                                $file = $trace[$idx + $offset]['file'];
-                                $line = $trace[$idx + $offset]['line'];
-                                break;
-                            }
-                        }
-                        DeprecationsPanel::addDeprecatedError(compact('code', 'message', 'file', 'line', 'context'));
-
-                        return;
-                    }
-                    if ($previousHandler) {
-                        $context['_trace_frame_offset'] = 1;
-
-                        return $previousHandler($code, $message, $file, $line, $context);
-                    }
+            EventManager::instance()->on('Error.handled', function (EventInterface $event, PhpError $error) {
+                $code = $error->getCode();
+                if ($code !== E_USER_DEPRECATED && $code !== E_DEPRECATED) {
+                    return;
+                }
+                $file = $error->getFile();
+                $line = $error->getLine();
 
-                    return false;
+                // Extract the line/file from the message as deprecationWarning
+                // will calculate the application frame when generating the message.
+                preg_match('/\\n([^\n,]+?), line: (\d+)\\n/', $error->getMessage(), $matches);
+                if ($matches) {
+                    $file = $matches[1];
+                    $line = $matches[2];
                 }
-            );
+
+                DeprecationsPanel::addDeprecatedError([
+                    'code' => $code,
+                    'message' => $error->getMessage(),
+                    'file' => $file,
+                    'line' => $line,
+                ]);
+            });
         }
     }
 }

tests/TestCase/PluginTest.php

@@ -14,6 +14,7 @@
  */
 namespace DebugKit\Test\TestCase;
 
+use Cake\Error\PhpError;
 use Cake\Event\Event;
 use Cake\Event\EventManager;
 use Cake\TestSuite\TestCase;
@@ -37,28 +38,44 @@ public function testSetDeprecationHandler()
         $service = new ToolbarService(new EventManager(), []);
         $plugin = new Plugin();
         $plugin->setDeprecationHandler($service);
-        $event = new Event('');
         $panel = new DeprecationsPanel();
 
-        //Without setting the $stackFrame
-        deprecationWarning('setDeprecationHandler');
-        //Setting the $stackFrame
-        deprecationWarning('setDeprecationHandler_2', 2);
-        //Raw error
-        $line = __LINE__ + 1;
-        trigger_error('raw_error', E_USER_DEPRECATED);
+        $error = new PhpError(E_USER_WARNING, 'ignored', __FILE__, __LINE__, []);
+        $event = new Event('Error.handled', null, ['error' => $error]);
+        EventManager::instance()->dispatch($event);
+
+        // No file/line in message.
+        $error = new PhpError(E_USER_DEPRECATED, 'going away', __FILE__, __LINE__, []);
+        $event = new Event('Error.handled', null, ['error' => $error]);
+        EventManager::instance()->dispatch($event);
+
+        // Formatted like deprecationWarning()
+        $message = <<<TEXT
+Something deprecated happened.
+Don't use that thing.
+src/Plugin.php, line: 51
+You can disable all deprecation warnings by setting `Error.errorLevel` to `E_ALL & ~E_USER_DEPRECATED`.
+TEXT;
+        $error = new PhpError(E_USER_DEPRECATED, $message, __FILE__, __LINE__, []);
+        $event = new Event('Error.handled', null, ['error' => $error]);
+        EventManager::instance()->dispatch($event);
 
         $panel->shutdown($event);
-        $data = $panel->data()['plugins']['DebugKit'];
+        $data = $panel->data();
+
+        $this->assertArrayHasKey('plugins', $data);
+        $this->assertArrayHasKey('DebugKit', $data['plugins']);
+        $this->assertCount(1, $data['plugins']['DebugKit']);
 
-        $this->assertCount(3, $data);
+        $first = $data['plugins']['DebugKit'][0];
+        $this->assertEquals($first['message'], 'going away');
+        $this->assertEquals($first['file'], __FILE__);
+        $this->assertEquals($first['line'], 48);
 
-        //test first two deprecationWarning()
-        foreach ([$data[0], $data[1]] as $value) {
-            $this->assertStringContainsString($value['file'], $value['message']);
-            $this->assertStringContainsString("line: {$value['line']}", $value['message']);
-        }
-        //test raw error
-        $this->assertSame($line, $data[2]['line']);
+        $this->assertArrayHasKey('other', $data);
+        $parsed = $data['other'][0];
+        $this->assertEquals($parsed['message'], $message);
+        $this->assertEquals($parsed['file'], 'src/Plugin.php');
+        $this->assertEquals($parsed['line'], 51);
     }
 }