From c57daea7581fa71513724ff2df9174b4c2c007bf Mon Sep 17 00:00:00 2001
From: Adam Jordens <ajordens@netflix.com>
Date: Fri, 25 May 2018 11:38:49 -0700
Subject: [PATCH] perf(cats): Ensure that `previousSet` is actually a `Set`

This is a significant performance improvement for large types.
---
 .../netflix/spinnaker/cats/provider/DefaultProviderCache.java   | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cats/cats-core/src/main/java/com/netflix/spinnaker/cats/provider/DefaultProviderCache.java b/cats/cats-core/src/main/java/com/netflix/spinnaker/cats/provider/DefaultProviderCache.java
index 729fe52eeae..55d636b45c7 100644
--- a/cats/cats-core/src/main/java/com/netflix/spinnaker/cats/provider/DefaultProviderCache.java
+++ b/cats/cats-core/src/main/java/com/netflix/spinnaker/cats/provider/DefaultProviderCache.java
@@ -135,7 +135,7 @@ public void putCacheResult(String sourceAgentType, Collection<String> authoritat
         for (String type : allTypes) {
             final Collection<String> previousSet;
             if (authoritativeTypes.contains(type)) {
-                previousSet = getExistingSourceIdentifiers(type, sourceAgentType);
+                previousSet = new HashSet<>(getExistingSourceIdentifiers(type, sourceAgentType));
             } else {
                 previousSet = new HashSet<>();
             }