Move functions.php into Framework

app/bootstrap.php

@@ -31,8 +31,6 @@
 // Sets default autoload mappings, may be overridden in Bootstrap::create
 \Magento\Framework\App\Bootstrap::populateAutoloader(BP, []);
 
-require_once BP . '/app/functions.php';
-
 /* Custom umask value may be provided in optional mage_umask file in root */
 $umaskFile = BP . '/magento_umask';
 $mask = file_exists($umaskFile) ? octdec(file_get_contents($umaskFile)) : 002;

app/functions.php

@@ -1,22 +1,15 @@
 <?php
 /**
- * Copyright © Magento, Inc. All rights reserved.
- * See COPYING.txt for license details.
+ * @deprecated The global function __() is now loaded via Composer in the Magento Framework, the below require is only
+ *             for backwards compatibility reasons and this file will be removed in a future version
+ * @see        Magento\Framework\Phrase\__.php
  */
 
-/**
- * Create value-object \Magento\Framework\Phrase
- *
- * @return \Magento\Framework\Phrase
- */
-function __()
-{
-    $argc = func_get_args();
-
-    $text = array_shift($argc);
-    if (!empty($argc) && is_array($argc[0])) {
-        $argc = $argc[0];
+$vendorDir = require VENDOR_PATH;
+if (!function_exists('__')) {
+    if (file_exists(BP . '/lib/internal/Magento/Framework/Phrase/__.php')) {
+        require BP . '/lib/internal/Magento/Framework/Phrase/__.php';
+    } elseif (file_exists(BP . "/{$vendorDir}/magento/framework/Phrase/__.php")) {
+        require BP . "/{$vendorDir}/magento/framework/Phrase/__.php";
     }
-
-    return new \Magento\Framework\Phrase($text, $argc);
 }

dev/tests/unit/framework/bootstrap.php

@@ -11,7 +11,6 @@
 }
 
 require_once __DIR__ . '/autoload.php';
-require BP . '/app/functions.php';
 
 setCustomErrorHandler();
 

lib/internal/Magento/Framework/Phrase/__.php

@@ -0,0 +1,22 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+
+/**
+ * Create value-object \Magento\Framework\Phrase
+ *
+ * @return \Magento\Framework\Phrase
+ */
+function __()
+{
+    $argc = func_get_args();
+
+    $text = array_shift($argc);
+    if (!empty($argc) && is_array($argc[0])) {
+        $argc = $argc[0];
+    }
+
+    return new \Magento\Framework\Phrase($text, $argc);
+}

lib/internal/Magento/Framework/Phrase/registration.php

@@ -0,0 +1,4 @@
+<?php
+if (!function_exists('__')) {
+    require '__.php';
+}

lib/internal/Magento/Framework/composer.json

@@ -53,7 +53,8 @@
             "Magento\\Framework\\": ""
         },
         "files": [
-            "registration.php"
+            "registration.php",
+            "Phrase/__.php"
         ]
     }
 }