Issue #2597644 by Mile23: ComposerIntegrationTest::testAllModulesReplaced() doesn't test anything

core/composer.json

@@ -89,6 +89,7 @@
     "drupal/help": "self.version",
     "drupal/history": "self.version",
     "drupal/image": "self.version",
+    "drupal/inline_form_errors": "self.version",
     "drupal/language": "self.version",
     "drupal/link": "self.version",
     "drupal/locale": "self.version",

core/tests/Drupal/Tests/ComposerIntegrationTest.php

@@ -75,20 +75,33 @@ public function testComposerJson() {
    * core's composer.json.
    */
   public function testAllModulesReplaced() {
+    // Assemble a path to core modules.
+    $module_path = $this->root . '/core/modules';
+
+    // Grab the 'replace' section of the core composer.json file.
     $json = json_decode(file_get_contents($this->root . '/core/composer.json'));
-    $composer_replace_packages = $json->replace;
+    $composer_replace_packages = (array) $json->replace;
 
-    $folders = scandir($this->root . '/core/modules');
+    // Get a list of all the files in the module path.
+    $folders = scandir($module_path);
 
+    // Make sure we only deal with directories that aren't . or ..
     $module_names = [];
+    $discard = ['.', '..'];
     foreach ($folders as $file_name) {
-      if ($file_name !== '.' && $file_name !== '..' && is_dir($file_name)) {
+      if ((!in_array($file_name, $discard)) && is_dir($module_path . '/' . $file_name)) {
         $module_names[] = $file_name;
       }
     }
 
+    // Assert that each core module has a corresponding 'replace' in
+    // composer.json.
     foreach ($module_names as $module_name) {
-      $this->assertTrue(array_key_exists('drupal/'.$module_name, $composer_replace_packages), 'Found ' . $module_name . ' in replace list of composer.json');
+      $this->assertArrayHasKey(
+        'drupal/' . $module_name,
+        $composer_replace_packages,
+        'Unable to find ' . $module_name . ' in replace list of composer.json'
+      );
     }
   }