Real composer patches format

hooks/RoboFile.php

@@ -190,12 +190,30 @@ public function updateDependencies()
      */
     protected function getPatches($module)
     {
-        $path = 'modules/' . $module . '/patches.json';
-        if (file_exists($path)) {
-            return json_decode(file_get_contents($path));
-        } else {
-            return new stdClass();
-        }
+      // Load composer configuration for the given module.
+      $config = json_decode(file_get_contents('modules/' . $module . '/composer.json'));
+
+      // If the module defines patches in composer.json, simply use them.
+      if (!empty($config->extra->{"patches"})) {
+        return $config->extra->{"patches"};
+      }
+
+      // Use the old patch file standard in drupal_tests, which was independent
+      // from any module composer.json patch specifications.
+      $patches_file = 'patches.json';
+
+      // If the module defines an external composer patches file, use it.
+      if (!empty($config->extra->{"patches-file"})) {
+        $patches_file = $config->extra->{"patches-file"};
+      }
+
+      $path = 'modules/' . $module . '/' . $patches_file;
+      if (file_exists($path)) {
+        $patch_file_contents = json_decode(file_get_contents($path));
+        return $patch_file_contents->{"patches"};
+      }
+
+      return new stdClass();
     }
 
     /**

templates/module/patches.json

@@ -1,5 +1,7 @@
 {
-  "drupal/coder": {
-    "CodeSniffer testing all file extensions instead of the configured ones": "https://www.drupal.org/files/issues/2867601.11-disable-txt-sniffs.patch"
+  "patches": {
+    "drupal/coder": {
+      "CodeSniffer testing all file extensions instead of the configured ones": "https://www.drupal.org/files/issues/2867601.11-disable-txt-sniffs.patch"
+    }
   }
 }