Issue #2927012 by deviantintegral, alexpott, arunkumark: _drupal_log_error()...

Issue #2927012 by deviantintegral, alexpott, arunkumark: _drupal_log_error() returns a 0 exit code on errors

core/includes/errors.inc

@@ -180,7 +180,7 @@ function _drupal_log_error($error, $fatal = FALSE) {
       // Should not translate the string to avoid errors producing more errors.
       $response->setContent(html_entity_decode(strip_tags(new FormattableMarkup('%type: @message in %function (line %line of %file).', $error))) . "\n");
       $response->send();
-      exit;
+      exit(1);
     }
   }
 

core/tests/Drupal/Tests/Core/Error/DrupalLogErrorTest.php

+<?php
+
+namespace Drupal\Tests\Core\Error;
+
+use Drupal\Tests\UnitTestCase;
+use Symfony\Component\Process\PhpProcess;
+
+/**
+ * Tests logging of errors in core/error.inc.
+ *
+ * @group Error
+ */
+class DrupalLogErrorTest extends UnitTestCase {
+
+  /**
+   * Test that fatal errors return a non-zero exit code.
+   */
+  public function testFatalExitCode() {
+    $script = <<<'EOT'
+<?php
+if (PHP_SAPI !== 'cli') {
+  return;
+}
+
+$autoloader = require_once 'autoload.php';
+require_once 'core/includes/bootstrap.inc';
+require_once 'core/includes/errors.inc';
+define('DRUPAL_TEST_IN_CHILD_SITE', FALSE);
+
+$error = [
+  '%type' => 'kernel test',
+  '@message' => 'This is a test message',
+  '%function' => 'test_function',
+  '%file' => 'test.module',
+  '%line' => 456,
+  '@backtrace_string' => 'backtrace',
+  'severity_level' => 0,
+  'backtrace' => [],
+];
+_drupal_log_error($error, TRUE);
+EOT;
+
+    // We need to override the current working directory for invocations from
+    // run-tests.sh to work properly.
+    $process = new PhpProcess($script, $this->root);
+    $process->run();
+
+    // Assert the output strings as unrelated errors (like the log-exit.php
+    // script throwing a PHP error) would still pass the final assertion.
+    $this->assertEquals("kernel test: This is a test message in test_function (line 456 of test.module).\n", $process->getOutput());
+    $this->assertEquals("kernel test: This is a test message in test.module on line 456 backtrace\n", $process->getErrorOutput());
+    $this->assertFalse($process->isSuccessful());
+  }
+
+}