diff vendor/psy/psysh/src/CodeCleaner/UseStatementPass.php @ 13:5fb285c0d0e3

Update Drupal core to 8.4.7 via Composer. Security update; I *think* we've
been lucky to get away with this so far, as we don't support self-registration
which seems to be used by the so-called "drupalgeddon 2" attack that 8.4.5
was vulnerable to.

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/vendor/psy/psysh/src/CodeCleaner/UseStatementPass.php	Mon Apr 23 09:33:26 2018 +0100
@@ -0,0 +1,126 @@
+<?php
+
+/*
+ * This file is part of Psy Shell.
+ *
+ * (c) 2012-2018 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\Name;
+use PhpParser\Node\Name\FullyQualified as FullyQualifiedName;
+use PhpParser\Node\Stmt\GroupUse;
+use PhpParser\Node\Stmt\Namespace_;
+use PhpParser\Node\Stmt\Use_;
+use PhpParser\NodeTraverser;
+
+/**
+ * Provide implicit use statements for subsequent execution.
+ *
+ * The use statement pass remembers the last use statement line encountered:
+ *
+ *     use Foo\Bar as Baz;
+ *
+ * ... which it then applies implicitly to all future evaluated code, until the
+ * current namespace is replaced by another namespace.
+ */
+class UseStatementPass extends CodeCleanerPass
+{
+    private $aliases       = [];
+    private $lastAliases   = [];
+    private $lastNamespace = null;
+
+    /**
+     * Re-load the last set of use statements on re-entering a namespace.
+     *
+     * This isn't how namespaces normally work, but because PsySH has to spin
+     * up a new namespace for every line of code, we do this to make things
+     * work like you'd expect.
+     *
+     * @param Node $node
+     */
+    public function enterNode(Node $node)
+    {
+        if ($node instanceof Namespace_) {
+            // If this is the same namespace as last namespace, let's do ourselves
+            // a favor and reload all the aliases...
+            if (strtolower($node->name) === strtolower($this->lastNamespace)) {
+                $this->aliases = $this->lastAliases;
+            }
+        }
+    }
+
+    /**
+     * If this statement is a namespace, forget all the aliases we had.
+     *
+     * If it's a use statement, remember the alias for later. Otherwise, apply
+     * remembered aliases to the code.
+     *
+     * @param Node $node
+     */
+    public function leaveNode(Node $node)
+    {
+        if ($node instanceof Use_) {
+            // Store a reference to every "use" statement, because we'll need
+            // them in a bit.
+            foreach ($node->uses as $use) {
+                $alias = $use->alias ?: end($use->name->parts);
+                $this->aliases[strtolower($alias)] = $use->name;
+            }
+
+            return NodeTraverser::REMOVE_NODE;
+        } elseif ($node instanceof GroupUse) {
+            // Expand every "use" statement in the group into a full, standalone
+            // "use" and store 'em with the others.
+            foreach ($node->uses as $use) {
+                $alias = $use->alias ?: end($use->name->parts);
+                $this->aliases[strtolower($alias)] = Name::concat($node->prefix, $use->name, [
+                    'startLine' => $node->prefix->getAttribute('startLine'),
+                    'endLine'   => $use->name->getAttribute('endLine'),
+                ]);
+            }
+
+            return NodeTraverser::REMOVE_NODE;
+        } elseif ($node instanceof Namespace_) {
+            // Start fresh, since we're done with this namespace.
+            $this->lastNamespace = $node->name;
+            $this->lastAliases   = $this->aliases;
+            $this->aliases       = [];
+        } else {
+            foreach ($node as $name => $subNode) {
+                if ($subNode instanceof Name) {
+                    // Implicitly thunk all aliases.
+                    if ($replacement = $this->findAlias($subNode)) {
+                        $node->$name = $replacement;
+                    }
+                }
+            }
+
+            return $node;
+        }
+    }
+
+    /**
+     * Find class/namespace aliases.
+     *
+     * @param Name $name
+     *
+     * @return FullyQualifiedName|null
+     */
+    private function findAlias(Name $name)
+    {
+        $that = strtolower($name);
+        foreach ($this->aliases as $alias => $prefix) {
+            if ($that === $alias) {
+                return new FullyQualifiedName($prefix->toString());
+            } elseif (substr($that, 0, strlen($alias) + 1) === $alias . '\\') {
+                return new FullyQualifiedName($prefix->toString() . substr($name, strlen($alias)));
+            }
+        }
+    }
+}