From 58fd5dad84e121417ccc9ef90afe5d1acad0114d Mon Sep 17 00:00:00 2001
From: Pol Dellaiera <pol.dellaiera@protonmail.com>
Date: Fri, 1 Dec 2023 11:03:06 +0100
Subject: [PATCH] fix: `pair` and `chunk` operation when using empty input
 (#327)

Fix https://github.com/loophp/collection/issues/326
---
 src/Operation/Chunk.php                          | 4 +++-
 tests/unit/Traits/GenericCollectionProviders.php | 7 +++++++
 2 files changed, 10 insertions(+), 1 deletion(-)

diff --git a/src/Operation/Chunk.php b/src/Operation/Chunk.php
index 333f280a4..81e6838fe 100644
--- a/src/Operation/Chunk.php
+++ b/src/Operation/Chunk.php
@@ -59,7 +59,9 @@ static function (iterable $iterable) use ($sizes): Generator {
                         $values = [$value];
                     }
 
-                    yield $values;
+                    if ([] !== $values) {
+                        yield $values;
+                    }
                 };
     }
 }
diff --git a/tests/unit/Traits/GenericCollectionProviders.php b/tests/unit/Traits/GenericCollectionProviders.php
index 423bbbca7..15dcfdb6a 100644
--- a/tests/unit/Traits/GenericCollectionProviders.php
+++ b/tests/unit/Traits/GenericCollectionProviders.php
@@ -3220,6 +3220,13 @@ public static function pairOperationProvider()
             $input,
             $output(),
         ];
+
+        yield [
+            $operation,
+            [],
+            [],
+            [],
+        ];
     }
 
     public static function permutateOperationProvider()