Functions: echo() can also be overridden

Env.php

@@ -34,6 +34,7 @@
  * @method bool date_default_timezone_set(string $timezone_identifier)
  * @method mixed set_error_handler(callable $error_handler, int $error_types = 32767)
  * @method callable set_exception_handler(callable $exception_handler)
+ * @method echo(string $arg1)
  */
 class Env
 {
@@ -108,10 +109,13 @@ public function __call($name, $arguments)
             }
             return call_user_func_array($callback, $arguments);
         }
-        if (!function_exists($name)) {
-            throw new FieldNotExist($name, 'global', null, $this);
+        if (function_exists($name)) {
+            return call_user_func_array($name, $arguments);
+        } elseif ($name === 'echo') {
+            echo implode(' ', $arguments);
+            return;
         }
-        return call_user_func_array($name, $arguments);
+        throw new FieldNotExist($name, 'global', null, $this);
     }
 
     /**

README.md

@@ -241,6 +241,8 @@ $env->header('Content-Type: text/plain'); // The header will not be sent
 
 Checking the existence of functions `$env->isFunctionExists(string $name):bool`.
 
+`echo()` can also be overridden.
+
 ##### Example
 
 Function `getallheaders()` not exist in all environments.

tests/EnvFunctionsTest.php

@@ -181,4 +181,26 @@ public function testCallMagic()
         ];
         $this->assertSame($expected, $headers);
     }
+
+    public function testEcho()
+    {
+        $echoed = null;
+        $config = [
+            'functions' => [
+                'echo' => function ($e) use (&$echoed) {
+                    $echoed = $e;
+                }
+            ],
+        ];
+        $envNormal = new Env([]);
+        $envEcho = new Env($config);
+        ob_start();
+        $envNormal->echo('one', 'two');
+        $envEcho->echo('three', 'four');
+        $out = ob_get_clean();
+        $this->assertSame('one two', $out);
+        $this->assertSame('three', $echoed);
+        $this->assertFalse($envNormal->isFunctionExists('echo'));
+        $this->assertTrue($envEcho->isFunctionExists('echo'));
+    }
 }