minor #42119 [Yaml] Remove compat code for MB function overloading (derrabus)

This PR was merged into the 6.0 branch.

Discussion
----------

[Yaml] Remove compat code for MB function overloading

| Q             | A
| ------------- | ---
| Branch?       | 6.0
| Bug fix?      | no
| New feature?  | no
| Deprecations? | no
| Tickets       | N/A
| License       | MIT
| Doc PR        | N/A

MB string function overloading has been removed with PHP 8.0. I'd like to remove some code that was meant to handle active function overloading.

Commits
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6028694781 [Yaml] Remove compat code for MB function overloading

Author: nicolas-grekas

Inline.php

@@ -66,42 +66,31 @@ public static function parse(string $value = null, int $flags = 0, array &$refer
             return '';
         }
 
-        if (2 /* MB_OVERLOAD_STRING */ & (int) ini_get('mbstring.func_overload')) {
-            $mbEncoding = mb_internal_encoding();
-            mb_internal_encoding('ASCII');
+        $i = 0;
+        $tag = self::parseTag($value, $i, $flags);
+        switch ($value[$i]) {
+            case '[':
+                $result = self::parseSequence($value, $flags, $i, $references);
+                ++$i;
+                break;
+            case '{':
+                $result = self::parseMapping($value, $flags, $i, $references);
+                ++$i;
+                break;
+            default:
+                $result = self::parseScalar($value, $flags, null, $i, null === $tag, $references);
         }
 
-        try {
-            $i = 0;
-            $tag = self::parseTag($value, $i, $flags);
-            switch ($value[$i]) {
-                case '[':
-                    $result = self::parseSequence($value, $flags, $i, $references);
-                    ++$i;
-                    break;
-                case '{':
-                    $result = self::parseMapping($value, $flags, $i, $references);
-                    ++$i;
-                    break;
-                default:
-                    $result = self::parseScalar($value, $flags, null, $i, null === $tag, $references);
-            }
-
-            // some comments are allowed at the end
-            if (preg_replace('/\s*#.*$/A', '', substr($value, $i))) {
-                throw new ParseException(sprintf('Unexpected characters near "%s".', substr($value, $i)), self::$parsedLineNumber + 1, $value, self::$parsedFilename);
-            }
-
-            if (null !== $tag && '' !== $tag) {
-                return new TaggedValue($tag, $result);
-            }
+        // some comments are allowed at the end
+        if (preg_replace('/\s*#.*$/A', '', substr($value, $i))) {
+            throw new ParseException(sprintf('Unexpected characters near "%s".', substr($value, $i)), self::$parsedLineNumber + 1, $value, self::$parsedFilename);
+        }
 
-            return $result;
-        } finally {
-            if (isset($mbEncoding)) {
-                mb_internal_encoding($mbEncoding);
-            }
+        if (null !== $tag && '' !== $tag) {
+            return new TaggedValue($tag, $result);
         }
+
+        return $result;
     }
 
     /**

Parser.php

@@ -82,19 +82,9 @@ public function parse(string $value, int $flags = 0): mixed
 
         $this->refs = [];
 
-        $mbEncoding = null;
-
-        if (2 /* MB_OVERLOAD_STRING */ & (int) ini_get('mbstring.func_overload')) {
-            $mbEncoding = mb_internal_encoding();
-            mb_internal_encoding('UTF-8');
-        }
-
         try {
             $data = $this->doParse($value, $flags);
         } finally {
-            if (null !== $mbEncoding) {
-                mb_internal_encoding($mbEncoding);
-            }
             $this->lines = [];
             $this->currentLine = '';
             $this->numberOfParsedLines = 0;