From d25356a09f9913f575201b4bdf0abd6827cd1e47 Mon Sep 17 00:00:00 2001
From: Thomas Steur <tsteur@users.noreply.github.com>
Date: Thu, 18 Jun 2020 08:52:36 +1200
Subject: [PATCH] Add legacy autoloader to support Matomo namespaces in 3.X 
 (#16069)

---
 LegacyAutoloader.php | 31 +++++++++++++++++++++++++++++++
 composer.json        |  3 ++-
 2 files changed, 33 insertions(+), 1 deletion(-)
 create mode 100644 LegacyAutoloader.php

diff --git a/LegacyAutoloader.php b/LegacyAutoloader.php
new file mode 100644
index 00000000000..44b4a62e282
--- /dev/null
+++ b/LegacyAutoloader.php
@@ -0,0 +1,31 @@
+<?php
+
+class LegacyAutoloader
+{
+    public function __construct()
+    {
+        spl_autoload_register(array($this, 'load_class'));
+    }
+
+    public static function register()
+    {
+        new LegacyAutoloader();
+    }
+
+    public function load_class($className)
+    {
+        if (strpos($className, 'Matomo\\') === 0) {
+            $newName = 'Piwik' . substr($className, 6);
+            if (class_exists($newName) && !class_exists($className, false)) {
+                @class_alias($newName, $className);
+            }
+        } elseif (strpos($className, 'Piwik\\') === 0) {
+            $newName = 'Matomo' . substr($className, 5);
+            if (class_exists($newName) && !class_exists($className, false)) {
+                @class_alias($newName, $className);
+            }
+        }
+    }
+}
+
+LegacyAutoloader::register();
\ No newline at end of file
diff --git a/composer.json b/composer.json
index 8abdfa457ca..0d2e58c1f29 100644
--- a/composer.json
+++ b/composer.json
@@ -144,7 +144,8 @@
             "HTML_": "libs/",
             "PEAR_": "libs/",
             "Archive_": "libs/"
-        }
+        },
+        "files": ["LegacyAutoloader.php"]
     },
     "autoload-dev": {
         "psr-4": {