From c6da9c1b7805f191f55219826dddd6144896b05f Mon Sep 17 00:00:00 2001
From: Gareth Kirwan <gbjkirwan@gmail.com>
Date: Sat, 17 Feb 2024 18:01:32 +0700
Subject: [PATCH] Subscription: Fix Match

---
 exchanges/stream/websocket.go          |  7 ++++++-
 exchanges/subscription/key.go          |  1 -
 exchanges/subscription/store.go        | 15 +++++++++------
 exchanges/subscription/subscription.go |  8 +++++---
 4 files changed, 20 insertions(+), 11 deletions(-)
 delete mode 100644 exchanges/subscription/key.go

diff --git a/exchanges/stream/websocket.go b/exchanges/stream/websocket.go
index 56c229cb99d..5fa1edb1356 100644
--- a/exchanges/stream/websocket.go
+++ b/exchanges/stream/websocket.go
@@ -872,7 +872,12 @@ func (w *Websocket) UnsubscribeChannels(channels subscription.List) error {
 		return fmt.Errorf("%s websocket: %w", w.exchangeName, errNoSubscriptionsSupplied)
 	}
 	if w.subscriptions == nil {
-		return nil
+		return common.ErrNilPointer
+	}
+	for _, s := range channels {
+		if w.subscriptions.Get(s) == nil {
+			return fmt.Errorf("%s websocket: %w: %s", w.exchangeName, ErrSubscriptionNotFound, s)
+		}
 	}
 	return w.Unsubscriber(channels)
 }
diff --git a/exchanges/subscription/key.go b/exchanges/subscription/key.go
deleted file mode 100644
index 0e1dae29986..00000000000
--- a/exchanges/subscription/key.go
+++ /dev/null
@@ -1 +0,0 @@
-package subscription
diff --git a/exchanges/subscription/store.go b/exchanges/subscription/store.go
index 365852b1718..8e833c6fd65 100644
--- a/exchanges/subscription/store.go
+++ b/exchanges/subscription/store.go
@@ -51,16 +51,19 @@ func (s *Store) Get(key any) *Subscription {
 }
 
 // get returns a pointer to subscription or nil if not found
-// If key implements MatchableKey then key.Match will be used
-// If key is actually a subscription then ensureKeyed will be used and we'll return the
+// If the key passed in is a Subscription then its Key will be used; which may be a pointer to itself.
+// If key implements MatchableKey then key.Match will be used; Note that *Subscription implements MatchableKey
 // This method provides no locking protection
-// returned subscriptions are implicitly guaranteed to have a key
+// returned subscriptions are implicitly guaranteed to have a Key
 func (s *Store) get(key any) *Subscription {
 	switch v := key.(type) {
-	case *Subscription:
-		return s.get(v.EnsureKeyed())
 	case Subscription:
-		return s.get(v.EnsureKeyed())
+		key = v.EnsureKeyed()
+	case *Subscription:
+		key = v.EnsureKeyed()
+	}
+
+	switch v := key.(type) {
 	case MatchableKey:
 		return s.match(v)
 	default:
diff --git a/exchanges/subscription/subscription.go b/exchanges/subscription/subscription.go
index 0be695a33a4..cdcbdc1c5fe 100644
--- a/exchanges/subscription/subscription.go
+++ b/exchanges/subscription/subscription.go
@@ -93,7 +93,7 @@ func (s *Subscription) EnsureKeyed() any {
 }
 
 // Match returns if the two keys match Channels, Assets, Pairs, Interval and Levels:
-// Pairs comparison:
+// Key Pairs comparison:
 // 1) Empty pairs then only Subscriptions without pairs match
 // 2) >=1 pairs then Subscriptions which contain all the pairs match
 // Such that a subscription for all enabled pairs will be matched when seaching for any one pair
@@ -103,8 +103,10 @@ func (s *Subscription) Match(key any) bool {
 	case !ok,
 		s.Channel != b.Channel,
 		s.Asset != b.Asset,
-		len(s.Pairs) == 0 && len(b.Pairs) != 0,
-		s.Pairs.ContainsAll(b.Pairs, true) != nil,
+		len(b.Pairs) == 0 && len(s.Pairs) != 0,
+		// len(b.Pairs) == 0 && len(s.Pairs) == 0: Okay; continue to next non-pairs check
+		len(b.Pairs) != 0 && len(s.Pairs) == 0,
+		len(b.Pairs) != 0 && s.Pairs.ContainsAll(b.Pairs, true) != nil,
 		s.Levels != b.Levels,
 		s.Interval != b.Interval:
 		return false