Primo Committ

vendor/psy/psysh/src/CodeCleaner/ListPass.php

@@ -0,0 +1,112 @@
+<?php
+
+/*
+ * This file is part of Psy Shell.
+ *
+ * (c) 2012-2022 Justin Hileman
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Psy\CodeCleaner;
+
+use PhpParser\Node;
+use PhpParser\Node\Expr;
+use PhpParser\Node\Expr\Array_;
+use PhpParser\Node\Expr\ArrayDimFetch;
+use PhpParser\Node\Expr\ArrayItem;
+use PhpParser\Node\Expr\Assign;
+use PhpParser\Node\Expr\FuncCall;
+use PhpParser\Node\Expr\List_;
+use PhpParser\Node\Expr\MethodCall;
+use PhpParser\Node\Expr\PropertyFetch;
+use PhpParser\Node\Expr\Variable;
+use Psy\Exception\ParseErrorException;
+
+/**
+ * Validate that the list assignment.
+ */
+class ListPass extends CodeCleanerPass
+{
+    private $atLeastPhp71;
+
+    public function __construct()
+    {
+        $this->atLeastPhp71 = \version_compare(\PHP_VERSION, '7.1', '>=');
+    }
+
+    /**
+     * Validate use of list assignment.
+     *
+     * @throws ParseErrorException if the user used empty with anything but a variable
+     *
+     * @param Node $node
+     */
+    public function enterNode(Node $node)
+    {
+        if (!$node instanceof Assign) {
+            return;
+        }
+
+        if (!$node->var instanceof Array_ && !$node->var instanceof List_) {
+            return;
+        }
+
+        if (!$this->atLeastPhp71 && $node->var instanceof Array_) {
+            $msg = "syntax error, unexpected '='";
+            throw new ParseErrorException($msg, $node->expr->getLine());
+        }
+
+        // Polyfill for PHP-Parser 2.x
+        $items = isset($node->var->items) ? $node->var->items : $node->var->vars;
+
+        if ($items === [] || $items === [null]) {
+            throw new ParseErrorException('Cannot use empty list', $node->var->getLine());
+        }
+
+        $itemFound = false;
+        foreach ($items as $item) {
+            if ($item === null) {
+                continue;
+            }
+
+            $itemFound = true;
+
+            // List_->$vars in PHP-Parser 2.x is Variable instead of ArrayItem.
+            if (!$this->atLeastPhp71 && $item instanceof ArrayItem && $item->key !== null) {
+                $msg = 'Syntax error, unexpected T_CONSTANT_ENCAPSED_STRING, expecting \',\' or \')\'';
+                throw new ParseErrorException($msg, $item->key->getLine());
+            }
+
+            if (!self::isValidArrayItem($item)) {
+                $msg = 'Assignments can only happen to writable values';
+                throw new ParseErrorException($msg, $item->getLine());
+            }
+        }
+
+        if (!$itemFound) {
+            throw new ParseErrorException('Cannot use empty list');
+        }
+    }
+
+    /**
+     * Validate whether a given item in an array is valid for short assignment.
+     *
+     * @param Expr $item
+     *
+     * @return bool
+     */
+    private static function isValidArrayItem(Expr $item): bool
+    {
+        $value = ($item instanceof ArrayItem) ? $item->value : $item;
+
+        while ($value instanceof ArrayDimFetch || $value instanceof PropertyFetch) {
+            $value = $value->var;
+        }
+
+        // We just kind of give up if it's a method call. We can't tell if it's
+        // valid via static analysis.
+        return $value instanceof Variable || $value instanceof MethodCall || $value instanceof FuncCall;
+    }
+}