[fix] restore missing pInterpolatedStringPart(), cover with test (#7741)

Author: TomasVotruba

rules-tests/DeadCode/Rector/Assign/RemoveDoubleAssignRector/Fixture/compare_interpolated_string.php.inc

@@ -0,0 +1,22 @@
+<?php
+
+namespace Rector\Tests\DeadCode\Rector\Assign\RemoveDoubleAssignRector\Fixture;
+
+final class CompareInterpolatedString
+{
+    public function run()
+    {
+        $markdown = 'a long string';
+
+        $markdown = preg_replace_callback(
+            function (array $matches): string {
+                $match = $matches[1];
+                $className = strtolower(Toolkit::toSlug($match));
+
+                return "<span class='tag tag-{$className}'>{$match}</span>";
+            },
+            (string)$markdown
+        );
+
+    }
+}

src/PhpParser/Printer/BetterStandardPrinter.php

@@ -21,6 +21,7 @@
 use PhpParser\Node\Expr\MethodCall;
 use PhpParser\Node\Expr\Ternary;
 use PhpParser\Node\Expr\Yield_;
+use PhpParser\Node\InterpolatedStringPart;
 use PhpParser\Node\Scalar\InterpolatedString;
 use PhpParser\Node\Scalar\String_;
 use PhpParser\Node\Stmt\Declare_;
@@ -112,6 +113,15 @@ public function pFileWithoutNamespace(FileWithoutNamespace $fileWithoutNamespace
         return $this->pStmts($fileWithoutNamespace->stmts);
     }
 
+    /**
+     * Use for standalone InterpolatedStringPart printing, that is not support by php-parser natively.
+     * Used e.g. in \Rector\PhpParser\Comparing\NodeComparator::printWithoutComments
+     */
+    protected function pInterpolatedStringPart(InterpolatedStringPart $interpolatedStringPart): string
+    {
+        return $interpolatedStringPart->value;
+    }
+
     protected function p(
         Node $node,
         int $precedence = self::MAX_PRECEDENCE,