feature #36003 [ErrorHandler][FrameworkBundle] better error messages in failing tests (guillbdx)

This PR was squashed before being merged into the 5.1-dev branch.

Discussion
----------

[ErrorHandler][FrameworkBundle] better error messages in failing tests

| Q             | A
| ------------- | ---
| Branch?       | master for features
| Bug fix?      | no
| New feature?  | yes
| Deprecations? | no
| Tickets       | Fix #32752
| License       | MIT
| Doc PR        |

Purpose of this PR is to enhance tests by giving a way to report an exception that occured during the processing of the request.

The ErrorHandler will add an X-Debug-Exception, and the assertThat() method of WebTestCase will throw an exception if this header exists and status code is 5xx.

In practice, this adds the "Caused by" section in this example:

```
Time: 374 ms, Memory: 20.00 MB

There was 1 failure:

1) App\Tests\Controller\HomeControllerTest::testC
Failed asserting that the Response has header "Content-Type" with value "application/json".

/srv/symfony/src/Symfony/Bundle/FrameworkBundle/Test/BrowserKitAssertionsTrait.php:132
/srv/symfony/src/Symfony/Bundle/FrameworkBundle/Test/BrowserKitAssertionsTrait.php:66
/srv/blog/tests/Controller/HomeControllerTest.php:29

Caused by
Exception: This a test exception. in /the/file.php:139
Stack trace:
[...]
```

Commits
-------

0da9469ee2 [ErrorHandler][FrameworkBundle] better error messages in failing tests

Author: fabpot

CHANGELOG.md

@@ -14,6 +14,7 @@ CHANGELOG
  * Deprecated *not* setting the "framework.router.utf8" configuration option as it will default to `true` in Symfony 6.0
  * Added tag `routing.expression_language_function` to define functions available in route conditions
  * Added `debug:container --deprecations` option to see compile-time deprecations.
+ * Made `BrowserKitAssertionsTrait` report the original error message in case of a failure
 
 5.0.0
 -----

Test/BrowserKitAssertionsTrait.php

@@ -11,8 +11,10 @@
 
 namespace Symfony\Bundle\FrameworkBundle\Test;
 
+use PHPUnit\Framework\Constraint\Constraint;
 use PHPUnit\Framework\Constraint\LogicalAnd;
 use PHPUnit\Framework\Constraint\LogicalNot;
+use PHPUnit\Framework\ExpectationFailedException;
 use Symfony\Component\BrowserKit\AbstractBrowser;
 use Symfony\Component\BrowserKit\Test\Constraint as BrowserKitConstraint;
 use Symfony\Component\HttpFoundation\Request;
@@ -28,12 +30,12 @@ trait BrowserKitAssertionsTrait
 {
     public static function assertResponseIsSuccessful(string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new ResponseConstraint\ResponseIsSuccessful(), $message);
+        self::assertThatForResponse(new ResponseConstraint\ResponseIsSuccessful(), $message);
     }
 
     public static function assertResponseStatusCodeSame(int $expectedCode, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new ResponseConstraint\ResponseStatusCodeSame($expectedCode), $message);
+        self::assertThatForResponse(new ResponseConstraint\ResponseStatusCodeSame($expectedCode), $message);
     }
 
     public static function assertResponseRedirects(string $expectedLocation = null, int $expectedCode = null, string $message = ''): void
@@ -46,42 +48,42 @@ public static function assertResponseRedirects(string $expectedLocation = null,
             $constraint = LogicalAnd::fromConstraints($constraint, new ResponseConstraint\ResponseStatusCodeSame($expectedCode));
         }
 
-        self::assertThat(self::getResponse(), $constraint, $message);
+        self::assertThatForResponse($constraint, $message);
     }
 
     public static function assertResponseHasHeader(string $headerName, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new ResponseConstraint\ResponseHasHeader($headerName), $message);
+        self::assertThatForResponse(new ResponseConstraint\ResponseHasHeader($headerName), $message);
     }
 
     public static function assertResponseNotHasHeader(string $headerName, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new LogicalNot(new ResponseConstraint\ResponseHasHeader($headerName)), $message);
+        self::assertThatForResponse(new LogicalNot(new ResponseConstraint\ResponseHasHeader($headerName)), $message);
     }
 
     public static function assertResponseHeaderSame(string $headerName, string $expectedValue, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new ResponseConstraint\ResponseHeaderSame($headerName, $expectedValue), $message);
+        self::assertThatForResponse(new ResponseConstraint\ResponseHeaderSame($headerName, $expectedValue), $message);
     }
 
     public static function assertResponseHeaderNotSame(string $headerName, string $expectedValue, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new LogicalNot(new ResponseConstraint\ResponseHeaderSame($headerName, $expectedValue)), $message);
+        self::assertThatForResponse(new LogicalNot(new ResponseConstraint\ResponseHeaderSame($headerName, $expectedValue)), $message);
     }
 
     public static function assertResponseHasCookie(string $name, string $path = '/', string $domain = null, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new ResponseConstraint\ResponseHasCookie($name, $path, $domain), $message);
+        self::assertThatForResponse(new ResponseConstraint\ResponseHasCookie($name, $path, $domain), $message);
     }
 
     public static function assertResponseNotHasCookie(string $name, string $path = '/', string $domain = null, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), new LogicalNot(new ResponseConstraint\ResponseHasCookie($name, $path, $domain)), $message);
+        self::assertThatForResponse(new LogicalNot(new ResponseConstraint\ResponseHasCookie($name, $path, $domain)), $message);
     }
 
     public static function assertResponseCookieValueSame(string $name, string $expectedValue, string $path = '/', string $domain = null, string $message = ''): void
     {
-        self::assertThat(self::getResponse(), LogicalAnd::fromConstraints(
+        self::assertThatForResponse(LogicalAnd::fromConstraints(
             new ResponseConstraint\ResponseHasCookie($name, $path, $domain),
             new ResponseConstraint\ResponseCookieValueSame($name, $expectedValue, $path, $domain)
         ), $message);
@@ -124,6 +126,21 @@ public static function assertRouteSame($expectedRoute, array $parameters = [], s
         self::assertThat(self::getRequest(), $constraint, $message);
     }
 
+    public static function assertThatForResponse(Constraint $constraint, string $message = ''): void
+    {
+        try {
+            self::assertThat(self::getResponse(), $constraint, $message);
+        } catch (ExpectationFailedException $exception) {
+            if (($serverExceptionMessage = self::getResponse()->headers->get('X-Debug-Exception'))
+                && ($serverExceptionFile = self::getResponse()->headers->get('X-Debug-Exception-File'))) {
+                $serverExceptionFile = explode(':', $serverExceptionFile);
+                $exception->__construct($exception->getMessage(), $exception->getComparisonFailure(), new \ErrorException(rawurldecode($serverExceptionMessage), 0, 1, rawurldecode($serverExceptionFile[0]), $serverExceptionFile[1]), $exception->getPrevious());
+            }
+
+            throw $exception;
+        }
+    }
+
     private static function getClient(AbstractBrowser $newClient = null): ?AbstractBrowser
     {
         static $client;

Tests/Test/WebTestCaseTest.php

@@ -12,6 +12,7 @@
 namespace Symfony\Bundle\FrameworkBundle\Tests\Test;
 
 use PHPUnit\Framework\AssertionFailedError;
+use PHPUnit\Framework\ExpectationFailedException;
 use PHPUnit\Framework\TestCase;
 use Symfony\Bundle\FrameworkBundle\KernelBrowser;
 use Symfony\Bundle\FrameworkBundle\Test\WebTestAssertionsTrait;
@@ -235,6 +236,17 @@ public function testAssertRouteSame()
         $this->getRequestTester()->assertRouteSame('articles');
     }
 
+    public function testExceptionOnServerError()
+    {
+        try {
+            $this->getResponseTester(new Response('', 500, ['X-Debug-Exception' => 'An exception has occurred', 'X-Debug-Exception-File' => '%2Fsrv%2Ftest.php:12']))->assertResponseIsSuccessful();
+        } catch (ExpectationFailedException $exception) {
+            $this->assertSame('An exception has occurred', $exception->getPrevious()->getMessage());
+            $this->assertSame('/srv/test.php', $exception->getPrevious()->getFile());
+            $this->assertSame(12, $exception->getPrevious()->getLine());
+        }
+    }
+
     private function getResponseTester(Response $response): WebTestCase
     {
         $client = $this->createMock(KernelBrowser::class);