--- /dev/null
+<?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\Name;
+use PhpParser\Node\Stmt\Namespace_;
+use Psy\CodeCleaner;
+
+/**
+ * Provide implicit namespaces for subsequent execution.
+ *
+ * The namespace pass remembers the last standalone namespace line encountered:
+ *
+ * namespace Foo\Bar;
+ *
+ * ... which it then applies implicitly to all future evaluated code, until the
+ * namespace is replaced by another namespace. To reset to the top level
+ * namespace, enter `namespace {}`. This is a bit ugly, but it does the trick :)
+ */
+class NamespacePass extends CodeCleanerPass
+{
+ private $namespace = null;
+ private $cleaner;
+
+ /**
+ * @param CodeCleaner $cleaner
+ */
+ public function __construct(CodeCleaner $cleaner)
+ {
+ $this->cleaner = $cleaner;
+ }
+
+ /**
+ * If this is a standalone namespace line, remember it for later.
+ *
+ * Otherwise, apply remembered namespaces to the code until a new namespace
+ * is encountered.
+ *
+ * @param array $nodes
+ */
+ public function beforeTraverse(array $nodes)
+ {
+ if (empty($nodes)) {
+ return $nodes;
+ }
+
+ $last = end($nodes);
+
+ if ($last instanceof Namespace_) {
+ $kind = $last->getAttribute('kind');
+
+ // Treat all namespace statements pre-PHP-Parser v3.1.2 as "open",
+ // even though we really have no way of knowing.
+ if ($kind === null || $kind === Namespace_::KIND_SEMICOLON) {
+ // Save the current namespace for open namespaces
+ $this->setNamespace($last->name);
+ } else {
+ // Clear the current namespace after a braced namespace
+ $this->setNamespace(null);
+ }
+
+ return $nodes;
+ }
+
+ return $this->namespace ? [new Namespace_($this->namespace, $nodes)] : $nodes;
+ }
+
+ /**
+ * Remember the namespace and (re)set the namespace on the CodeCleaner as
+ * well.
+ *
+ * @param null|Name $namespace
+ */
+ private function setNamespace($namespace)
+ {
+ $this->namespace = $namespace;
+ $this->cleaner->setNamespace($namespace === null ? null : $namespace->parts);
+ }
+}