From ed17544dc8cec9a52ff41a6c559061325fbc1e41 Mon Sep 17 00:00:00 2001
From: XedinUnknown <xedin.unknown@gmail.com>
Date: Wed, 3 Feb 2021 01:45:41 +0100
Subject: [PATCH 1/2] Add iteration capability to `SegmentingContainer`

---
 src/SegmentingContainer.php                   | 83 ++++++++++++++++++-
 .../MultipleAccessTypesWithMapsTest.php       |  4 +-
 2 files changed, 83 insertions(+), 4 deletions(-)

diff --git a/src/SegmentingContainer.php b/src/SegmentingContainer.php
index bf21b40..09439de 100644
--- a/src/SegmentingContainer.php
+++ b/src/SegmentingContainer.php
@@ -5,8 +5,15 @@
 namespace Dhii\Container;
 
 use Dhii\Collection\ContainerInterface;
+use Exception;
+use Iterator;
+use IteratorAggregate;
 use Psr\Container\ContainerInterface as PsrContainerInterface;
 
+use Traversable;
+
+use UnexpectedValueException;
+
 use function array_filter;
 use function ltrim;
 
@@ -53,7 +60,7 @@
  * @since [*next-version*]
  * @see   PathContainer For an implementation that achieves the opposite effect.
  */
-class SegmentingContainer implements ContainerInterface
+class SegmentingContainer implements ContainerInterface, Iterator
 {
     /**
      * @var PsrContainerInterface
@@ -70,6 +77,11 @@ class SegmentingContainer implements ContainerInterface
      */
     protected $delimiter;
 
+    /**
+     * @var Iterator
+     */
+    protected $iterator;
+
     /**
      * Constructor.
      *
@@ -116,4 +128,73 @@ public function has($key)
     {
         return $this->inner->has($key);
     }
+
+    public function current()
+    {
+        return $this->iterator->current();
+    }
+
+    public function next()
+    {
+        $this->iterator->next();
+    }
+
+    public function key()
+    {
+        return $this->iterator->key();
+    }
+
+    public function valid()
+    {
+        return $this->startsWith($this->iterator->key(), $this->root);
+    }
+
+    public function rewind()
+    {
+        if (!($this->inner instanceof Traversable)) {
+            throw new UnexpectedValueException('Cannot rewind: inner container not an iterator');
+        }
+
+        $this->iterator = $this->normalizeIterator($this->inner);
+        $this->iterator->rewind();
+    }
+
+    /**
+     * Normalizes a traversable into an iterator.
+     *
+     * This is helpful because an `Iterator` can be iterated over by explicitly calling known methods,
+     * which include those that expose the current key.
+     *
+     * @param Traversable $traversable The traversable to normalize.
+     *
+     * @return Iterator The normalized iterator.
+     *
+     * @throws Exception If problem normalizing.
+     */
+    protected function normalizeIterator(Traversable $traversable): Iterator
+    {
+        if ($traversable instanceof Iterator) {
+            return $traversable;
+        }
+
+        // Any `Traversable` that is not an `Iterator` is an `IteratorAggregate`
+        assert($traversable instanceof IteratorAggregate);
+        $traversable = $traversable->getIterator();
+
+        return $this->normalizeIterator($traversable);
+    }
+
+    /**
+     * Determines whether the subject string has another string at the start.
+     *
+     * @param string $subject The subject to check.
+     * @param string $start   The start string to check for.
+     *
+     * @return bool True if subject starts with specified start string; false otherwise.
+     */
+    protected function startsWith(string $subject, string $start): bool
+    {
+        $length = strlen($start);
+        return substr($subject, 0, $length) === $start;
+    }
 }
diff --git a/tests/system/MultipleAccessTypesWithMapsTest.php b/tests/system/MultipleAccessTypesWithMapsTest.php
index d54ade7..3149cee 100644
--- a/tests/system/MultipleAccessTypesWithMapsTest.php
+++ b/tests/system/MultipleAccessTypesWithMapsTest.php
@@ -8,7 +8,7 @@
 use Dhii\Container\SegmentingContainer;
 use PHPUnit\Framework\TestCase;
 
-class MultipleAccessTypesWithMaps__ extends TestCase
+class MultipleAccessTypesWithMaps extends TestCase
 {
     const DEV_DB_HOST = 'localhost';
     const STAGING_DB_HOST = '123.staging.myhost';
@@ -85,8 +85,6 @@ public function testPreserveIterabilityInNamespaced(array $devData, array $stagi
         }
 
         {
-            $this->markTestIncomplete('This will fail, because the segmenting container is not iterable, ' .
-                                      'and will return instances of itself for keys that are not found.');
             $this->assertIsIterable($container->get('staging')->get('db'));
         }
     }

From 15749984085304b84f51cd7817047b4806569fb8 Mon Sep 17 00:00:00 2001
From: XedinUnknown <xedin.unknown@gmail.com>
Date: Wed, 3 Feb 2021 02:12:46 +0100
Subject: [PATCH 2/2] Fix PHPCS

---
 src/SegmentingContainer.php | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/src/SegmentingContainer.php b/src/SegmentingContainer.php
index 09439de..a406430 100644
--- a/src/SegmentingContainer.php
+++ b/src/SegmentingContainer.php
@@ -9,9 +9,7 @@
 use Iterator;
 use IteratorAggregate;
 use Psr\Container\ContainerInterface as PsrContainerInterface;
-
 use Traversable;
-
 use UnexpectedValueException;
 
 use function array_filter;
@@ -134,7 +132,7 @@ public function current()
         return $this->iterator->current();
     }
 
-    public function next()
+    public function next(): void
     {
         $this->iterator->next();
     }
@@ -149,7 +147,7 @@ public function valid()
         return $this->startsWith($this->iterator->key(), $this->root);
     }
 
-    public function rewind()
+    public function rewind(): void
     {
         if (!($this->inner instanceof Traversable)) {
             throw new UnexpectedValueException('Cannot rewind: inner container not an iterator');