Add isolated container and dhii modularity deps

lib/packages/Dhii/Container/PrefixingContainer.php

@@ -0,0 +1,128 @@
+<?php
+
+declare(strict_types=1);
+
+namespace WooCommerce\PayPalCommerce\Vendor\Dhii\Container;
+
+use WooCommerce\PayPalCommerce\Vendor\Dhii\Collection\ContainerInterface;
+use WooCommerce\PayPalCommerce\Vendor\Dhii\Container\Exception\NotFoundException;
+use WooCommerce\PayPalCommerce\Vendor\Psr\Container\ContainerInterface as PsrContainerInterface;
+use WooCommerce\PayPalCommerce\Vendor\Psr\Container\NotFoundExceptionInterface;
+
+/**
+ * A container implementation that wraps around an inner container and prefixes its keys, requiring consumers to
+ * include them when fetching or looking up data.
+ *
+ * @since [*next-version*]
+ */
+class PrefixingContainer implements ContainerInterface
+{
+    /**
+     * @since [*next-version*]
+     *
+     * @var PsrContainerInterface
+     */
+    protected $inner;
+
+    /**
+     * @since [*next-version*]
+     *
+     * @var string
+     */
+    protected $prefix;
+
+    /**
+     * @since [*next-version*]
+     *
+     * @var bool
+     */
+    protected $strict;
+
+    /**
+     * Constructor.
+     *
+     * @since [*next-version*]
+     *
+     * @param PsrContainerInterface $container The container whose keys to prefix.
+     * @param string                $prefix    The prefix to apply to the container's keys.
+     * @param bool                  $strict    Whether or not to fallback to un-prefixed keys if a prefixed key does not
+     *                                         exist in the inner container.
+     */
+    public function __construct(PsrContainerInterface $container, string $prefix, bool $strict = true)
+    {
+        $this->inner = $container;
+        $this->prefix = $prefix;
+        $this->strict = $strict;
+    }
+
+    /**
+     * @inheritdoc
+     *
+     * @since [*next-version*]
+     */
+    public function get($key)
+    {
+        if (!$this->isPrefixed($key) && $this->strict) {
+            throw new NotFoundException(sprintf('Key "%s" does not exist', $key));
+        }
+
+        /**
+         * @psalm-suppress InvalidCatch
+         * The base interface does not extend Throwable, but in fact everything that is possible
+         * in theory to catch will be Throwable, and PSR-11 exceptions will implement this interface
+         */
+        try {
+            return $this->inner->get($this->unprefix($key));
+        } catch (NotFoundExceptionInterface $nfException) {
+            if ($this->strict) {
+                throw $nfException;
+            }
+        }
+
+        return $this->inner->get($key);
+    }
+
+    /**
+     * @inheritdoc
+     *
+     * @since [*next-version*]
+     */
+    public function has($key)
+    {
+        if (!$this->isPrefixed($key) && $this->strict) {
+            return false;
+        }
+
+        return $this->inner->has($this->unprefix($key)) || (!$this->strict && $this->inner->has($key));
+    }
+
+    /**
+     * Retrieves the key to use for the inner container.
+     *
+     * @since [*next-version*]
+     *
+     * @param string $key The outer key.
+     *
+     * @return string The inner key.
+     */
+    protected function unprefix(string $key): string
+    {
+        return $this->isPrefixed($key)
+            ? substr($key, strlen($this->prefix))
+            : $key;
+    }
+
+    /**
+     * Checks if the key is prefixed.
+     *
+     * @since [*next-version*]
+     *
+     * @param string $key The key to check.
+     *
+     * @return bool True if the key is prefixed, false if not.
+     */
+    protected function isPrefixed(string $key): bool
+    {
+        return strlen($this->prefix) > 0 && strpos($key, $this->prefix) === 0;
+    }
+}