From 6499302983abccc892c158e2d67ee2ba9ac97b78 Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Mon, 25 Oct 2021 17:48:35 -0700
Subject: [PATCH] Always cache union and intersection relations

---
 src/compiler/checker.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index ed75651e6e..32b3f3e09c 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -18207,7 +18207,7 @@ namespace ts {
                 let result = Ternary.False;
                 const saveErrorInfo = captureErrorCalculationState();
 
-                if ((source.flags & TypeFlags.Union || target.flags & TypeFlags.Union) && getConstituentCount(source) * getConstituentCount(target) < 4) {
+                if ((source.flags & TypeFlags.Union || target.flags & TypeFlags.Union) && getConstituentCount(source) * getConstituentCount(target) < 0) {
                     // We skip caching when source or target is a union with no more than three constituents.
                     result = structuredTypeRelatedTo(source, target, reportErrors, intersectionState | IntersectionState.UnionIntersectionCheck);
                 }