From c638e81308ab0958239ac80e27bf4c75b816193e Mon Sep 17 00:00:00 2001
From: Franz Busch <f.busch@apple.com>
Date: Tue, 19 Sep 2023 17:06:37 +0200
Subject: [PATCH] Fix `chunks(countOf: 1)`

# Motivation
We were failing to properly chunk a sequence if the count was `1` since we only checked for count equality on the second element but never the first one.
---
 Sources/AsyncAlgorithms/AsyncChunksOfCountSequence.swift | 4 ++++
 Tests/AsyncAlgorithmsTests/TestChunk.swift               | 8 ++++++++
 2 files changed, 12 insertions(+)

diff --git a/Sources/AsyncAlgorithms/AsyncChunksOfCountSequence.swift b/Sources/AsyncAlgorithms/AsyncChunksOfCountSequence.swift
index 9e1c4959..0ebafb4b 100644
--- a/Sources/AsyncAlgorithms/AsyncChunksOfCountSequence.swift
+++ b/Sources/AsyncAlgorithms/AsyncChunksOfCountSequence.swift
@@ -49,6 +49,10 @@ public struct AsyncChunksOfCountSequence<Base: AsyncSequence, Collected: RangeRe
         return nil
       }
 
+      if count == 1 {
+        return Collected(CollectionOfOne(first))
+      }
+
       var result: Collected = .init()
       result.append(first)
 
diff --git a/Tests/AsyncAlgorithmsTests/TestChunk.swift b/Tests/AsyncAlgorithmsTests/TestChunk.swift
index eee61247..7845b1a0 100644
--- a/Tests/AsyncAlgorithmsTests/TestChunk.swift
+++ b/Tests/AsyncAlgorithmsTests/TestChunk.swift
@@ -24,6 +24,14 @@ func concatCharacters(_ array: [String]) -> String {
 }
 
 final class TestChunk: XCTestCase {
+  func test_count_one() {
+    validate {
+      "ABCDE|"
+      $0.inputs[0].chunks(ofCount: 1).map(concatCharacters)
+      "ABCDE|"
+    }
+  }
+
   func test_signal_equalChunks() {
     validate {
       "ABC-    DEF-    GHI-     |"