From a277737387660846744325093f5cb37e913e8861 Mon Sep 17 00:00:00 2001
From: Filippo Tessarotto <zoeslam@gmail.com>
Date: Thu, 20 May 2021 16:05:55 +0200
Subject: [PATCH] Iterable return types should return empty array by default

---
 src/Framework/MockObject/Invocation.php       |  2 +-
 ...clarations_generator_empty_by_default.phpt | 27 +++++++++++++++++++
 2 files changed, 28 insertions(+), 1 deletion(-)
 create mode 100644 tests/end-to-end/mock-objects/generator/return_type_declarations_generator_empty_by_default.phpt

diff --git a/src/Framework/MockObject/Invocation.php b/src/Framework/MockObject/Invocation.php
index bedfebf1be3..4151dc15f38 100644
--- a/src/Framework/MockObject/Invocation.php
+++ b/src/Framework/MockObject/Invocation.php
@@ -152,7 +152,7 @@ public function generateReturnValue()
             case 'generator':
             case 'iterable':
                 $generator = static function () {
-                    yield;
+                    yield from [];
                 };
 
                 return $generator();
diff --git a/tests/end-to-end/mock-objects/generator/return_type_declarations_generator_empty_by_default.phpt b/tests/end-to-end/mock-objects/generator/return_type_declarations_generator_empty_by_default.phpt
new file mode 100644
index 00000000000..d5f7bfe232d
--- /dev/null
+++ b/tests/end-to-end/mock-objects/generator/return_type_declarations_generator_empty_by_default.phpt
@@ -0,0 +1,27 @@
+--TEST--
+Iterable return types should return empty array by default
+--FILE--
+<?php declare(strict_types=1);
+interface Foo
+{
+    public function forTraversable(): traversable;
+    public function forGenerator(): Generator;
+    public function forIterable(): iterable;
+}
+
+require __DIR__ . '/../../../../vendor/autoload.php';
+
+$generator = new \PHPUnit\Framework\MockObject\Generator;
+
+$mock = $generator->getMock('Foo');
+
+var_dump(iterator_to_array($mock->forTraversable()));
+var_dump(iterator_to_array($mock->forGenerator()));
+var_dump(iterator_to_array($mock->forIterable()));
+--EXPECTF--
+array(0) {
+}
+array(0) {
+}
+array(0) {
+}