[TASK] Deprecate method forwarding OutputFormat to OutputFormatter

Instead, the corresponding method on the formatter should be called
directly.

This increases type safety and helps static code analysis. Also, it
makes the code easier to understand.

Author: oliverklee

CHANGELOG.md

@@ -34,6 +34,8 @@ Please also have a look at our
 
 ### Deprecated
 
+- Deprecate magic method forwarding from `OutputFormat` to `OutputFormatter`
+  (#894)
 - Deprecate greedy calculation of selector specificity (#1018)
 - Deprecate `__toString()` (#1006)
 - `OutputFormat` properties for space around list separators as an array (#880)

src/OutputFormat.php

@@ -244,6 +244,7 @@ public function set($aNames, $mValue)
     public function __call(string $sMethodName, array $aArguments)
     {
         if (\method_exists(OutputFormatter::class, $sMethodName)) {
+            // @deprecated since 8.8.0, will be removed in 9.0.0. Call the method on the formatter directly instead.
             return \call_user_func_array([$this->getFormatter(), $sMethodName], $aArguments);
         } else {
             throw new \Exception('Unknown OutputFormat method called: ' . $sMethodName);