From 2cbad3312aefc95f0cf19ad7b2cc30faba727bcd Mon Sep 17 00:00:00 2001
From: Tristan Celder <tristan.celder@gmail.com>
Date: Sun, 19 Apr 2020 09:54:31 +0100
Subject: [PATCH] Standardised ReplaySubject double subscribe behaviour

Thanks, @jasdev, for the heads-up!
---
 Sources/Entwine/Operators/ReplaySubject.swift |  1 -
 Tests/EntwineTests/ReplaySubjectTests.swift   | 22 +++++++++++++++++++
 2 files changed, 22 insertions(+), 1 deletion(-)

diff --git a/Sources/Entwine/Operators/ReplaySubject.swift b/Sources/Entwine/Operators/ReplaySubject.swift
index d0f5095..fb90c9d 100644
--- a/Sources/Entwine/Operators/ReplaySubject.swift
+++ b/Sources/Entwine/Operators/ReplaySubject.swift
@@ -58,7 +58,6 @@ extension ReplaySubject: Publisher {
         
         guard !subscriberIdentifiers.contains(subscriber.combineIdentifier) else {
             subscriber.receive(subscription: Subscriptions.empty)
-            subscriber.receive(completion: .finished)
             return
         }
         
diff --git a/Tests/EntwineTests/ReplaySubjectTests.swift b/Tests/EntwineTests/ReplaySubjectTests.swift
index a5eaadc..33b44dc 100644
--- a/Tests/EntwineTests/ReplaySubjectTests.swift
+++ b/Tests/EntwineTests/ReplaySubjectTests.swift
@@ -451,6 +451,28 @@ final class ReplaySubjectTests: XCTestCase {
         
         XCTAssertEqual(results2.recordedOutput, results1.recordedOutput)
     }
+    
+    func testDuplicateSubscriptionMatchesControl() {
+        
+        var subject: ReplaySubject<Int, Never>! = nil
+        var control: PassthroughSubject<Int, Never>! = nil
+        
+        let results1 = scheduler.createTestableSubscriber(Int.self, Never.self)
+        let results2 = scheduler.createTestableSubscriber(Int.self, Never.self)
+        
+        scheduler.schedule(after: 100) { subject = ReplaySubject(maxBufferSize: 1) }
+        scheduler.schedule(after: 100) { control = PassthroughSubject() }
+        scheduler.schedule(after: 200) { subject.subscribe(results1) }
+        scheduler.schedule(after: 200) { control.subscribe(results2) }
+        scheduler.schedule(after: 300) { subject.subscribe(results1) }
+        scheduler.schedule(after: 300) { control.subscribe(results2) }
+        scheduler.schedule(after: 400) { subject = nil }
+        scheduler.schedule(after: 400) { control = nil }
+        
+        scheduler.resume()
+        
+        XCTAssertEqual(results2.recordedOutput, results1.recordedOutput)
+    }
 
     func testSendSubscriptionInitialDemandUnlimitedBehaviorMatchesControl() {