Don't make VariadicPlaceholder an expression

And don't store it in an Arg.

Author: nikic

CHANGELOG.md

@@ -6,8 +6,8 @@ Version 4.12.1-dev
 * [PHP 8.1] Added support for intersection types using a new `IntersectionType` node.
 * [PHP 8.1] Added support for explicit octal literals.
 * [PHP 8.1] Added support for first-class callables. These are represented using a call whose first
-  `Arg->expr` is an `Expr\VariadicPlaceholder`. The representation is intended to be
-  forward-compatible with partial function application, just like the PHP feature itself.
+  argument is a `VariadicPlaceholder`. The representation is intended to be forward-compatible with
+  partial function application, just like the PHP feature itself.
 
 Version 4.12.0 (2021-07-21)
 ---------------------------

grammar/php7.y

@@ -623,8 +623,7 @@ argument_list:
 ;
 
 variadic_placeholder:
-      T_ELLIPSIS
-          { $$ = Node\Arg[Node\VariadicPlaceholder[], false, false]; }
+      T_ELLIPSIS                                            { $$ = Node\VariadicPlaceholder[]; }
 ;
 
 non_empty_argument_list:

lib/PhpParser/Node/Arg.php

@@ -2,7 +2,7 @@
 
 namespace PhpParser\Node;
 
-use PhpParser\Node\Expr\VariadicPlaceholder;
+use PhpParser\Node\VariadicPlaceholder;
 use PhpParser\NodeAbstract;
 
 class Arg extends NodeAbstract

…Parser/Node/Expr/VariadicPlaceholder.php …b/PhpParser/Node/VariadicPlaceholder.phplib/PhpParser/Node/Expr/VariadicPlaceholder.php renamed to lib/PhpParser/Node/VariadicPlaceholder.php lib/PhpParser/Node/Expr/VariadicPlaceholder.php renamed to lib/PhpParser/Node/VariadicPlaceholder.php

@@ -1,13 +1,13 @@
 <?php declare(strict_types=1);
 
-namespace PhpParser\Node\Expr;
+namespace PhpParser\Node;
 
-use PhpParser\Node\Expr;
+use PhpParser\NodeAbstract;
 
 /**
  * Represents the "..." in "foo(...)" of the first-class callable syntax.
  */
-class VariadicPlaceholder extends Expr {
+class VariadicPlaceholder extends NodeAbstract {
     /**
      * Create a variadic argument placeholder (first-class callable syntax).
      *
@@ -18,7 +18,7 @@ public function __construct(array $attributes = []) {
     }
 
     public function getType(): string {
-        return 'Expr_VariadicPlaceholder';
+        return 'VariadicPlaceholder';
     }
 
     public function getSubNodeNames(): array {

lib/PhpParser/Parser/Php7.php

@@ -1934,7 +1934,7 @@ protected function initReduceCallbacks() {
                  $this->semValue = array($this->semStack[$stackPos-(3-2)]);
             },
             310 => function ($stackPos) {
-                 $this->semValue = new Node\Arg(new Expr\VariadicPlaceholder($this->startAttributeStack[$stackPos-(1-1)] + $this->endAttributes), false, false, $this->startAttributeStack[$stackPos-(1-1)] + $this->endAttributes);
+                 $this->semValue = new Node\VariadicPlaceholder($this->startAttributeStack[$stackPos-(1-1)] + $this->endAttributes);
             },
             311 => function ($stackPos) {
                  $this->semValue = array($this->semStack[$stackPos-(1-1)]);

lib/PhpParser/PrettyPrinter/Standard.php

@@ -33,6 +33,10 @@ protected function pArg(Node\Arg $node) {
              . $this->p($node->value);
     }
 
+    protected function pVariadicPlaceholder(Node\VariadicPlaceholder $node) {
+        return '...';
+    }
+
     protected function pConst(Node\Const_ $node) {
         return $node->name . ' = ' . $this->p($node->value);
     }
@@ -692,10 +696,6 @@ protected function pExpr_Yield(Expr\Yield_ $node) {
         }
     }
 
-    protected function pExpr_VariadicPlaceholder(Expr\VariadicPlaceholder $node) {
-        return '...';
-    }
-
     // Declarations
 
     protected function pStmt_Namespace(Stmt\Namespace_ $node) {

test/code/parser/expr/firstClassCallables.test

@@ -21,12 +21,7 @@ array(
                 )
             )
             args: array(
-                0: Arg(
-                    name: null
-                    value: Expr_VariadicPlaceholder(
-                    )
-                    byRef: false
-                    unpack: false
+                0: VariadicPlaceholder(
                 )
             )
         )
@@ -40,12 +35,7 @@ array(
                 name: foo
             )
             args: array(
-                0: Arg(
-                    name: null
-                    value: Expr_VariadicPlaceholder(
-                    )
-                    byRef: false
-                    unpack: false
+                0: VariadicPlaceholder(
                 )
             )
         )
@@ -61,12 +51,7 @@ array(
                 name: foo
             )
             args: array(
-                0: Arg(
-                    name: null
-                    value: Expr_VariadicPlaceholder(
-                    )
-                    byRef: false
-                    unpack: false
+                0: VariadicPlaceholder(
                 )
             )
         )
@@ -79,12 +64,7 @@ array(
                 )
             )
             args: array(
-                0: Arg(
-                    name: null
-                    value: Expr_VariadicPlaceholder(
-                    )
-                    byRef: false
-                    unpack: false
+                0: VariadicPlaceholder(
                 )
             )
             comments: array(
@@ -106,12 +86,7 @@ array(
                             )
                         )
                         args: array(
-                            0: Arg(
-                                name: null
-                                value: Expr_VariadicPlaceholder(
-                                )
-                                byRef: false
-                                unpack: false
+                            0: VariadicPlaceholder(
                             )
                         )
                     )