Initial Commit

dependencies/amphp/byte-stream/lib/IteratorStream.php

@@ -0,0 +1,55 @@
+<?php
+
+namespace WP_Ultimo\Dependencies\Amp\ByteStream;
+
+use WP_Ultimo\Dependencies\Amp\Deferred;
+use WP_Ultimo\Dependencies\Amp\Failure;
+use WP_Ultimo\Dependencies\Amp\Iterator;
+use WP_Ultimo\Dependencies\Amp\Promise;
+final class IteratorStream implements InputStream
+{
+    /** @var Iterator<string> */
+    private $iterator;
+    /** @var \Throwable|null */
+    private $exception;
+    /** @var bool */
+    private $pending = \false;
+    /**
+     * @psam-param Iterator<string> $iterator
+     */
+    public function __construct(Iterator $iterator)
+    {
+        $this->iterator = $iterator;
+    }
+    /** @inheritdoc */
+    public function read() : Promise
+    {
+        if ($this->exception) {
+            return new Failure($this->exception);
+        }
+        if ($this->pending) {
+            throw new PendingReadError();
+        }
+        $this->pending = \true;
+        /** @var Deferred<string|null> $deferred */
+        $deferred = new Deferred();
+        $this->iterator->advance()->onResolve(function ($error, $hasNextElement) use($deferred) {
+            $this->pending = \false;
+            if ($error) {
+                $this->exception = $error;
+                $deferred->fail($error);
+            } elseif ($hasNextElement) {
+                $chunk = $this->iterator->getCurrent();
+                if (!\is_string($chunk)) {
+                    $this->exception = new StreamException(\sprintf("Unexpected iterator value of type '%s', expected string", \is_object($chunk) ? \get_class($chunk) : \gettype($chunk)));
+                    $deferred->fail($this->exception);
+                    return;
+                }
+                $deferred->resolve($chunk);
+            } else {
+                $deferred->resolve();
+            }
+        });
+        return $deferred->promise();
+    }
+}