From 40a5fc1189d7a6591fe125ab5716af317829aa8d Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Sun, 28 Aug 2022 08:11:10 -0700
Subject: [PATCH] Handle intersections in
 isGenericTypeWithoutNullableConstraint

---
 src/compiler/checker.ts | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index f1dacf1f1eee2..2609d14d0fd2f 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -25789,8 +25789,10 @@ namespace ts {
                 !!(type.flags & TypeFlags.Instantiable && getBaseConstraintOrType(type).flags & (TypeFlags.Nullable | TypeFlags.Union));
         }
 
-        function isGenericTypeWithoutNullableConstraint(type: Type) {
-            return !!(type.flags & TypeFlags.Instantiable && !maybeTypeOfKind(getBaseConstraintOrType(type), TypeFlags.Nullable));
+        function isGenericTypeWithoutNullableConstraint(type: Type): boolean {
+            return type.flags & TypeFlags.Intersection ?
+                some((type as IntersectionType).types, isGenericTypeWithoutNullableConstraint) :
+                !!(type.flags & TypeFlags.Instantiable && !maybeTypeOfKind(getBaseConstraintOrType(type), TypeFlags.Nullable));
         }
 
         function hasContextualTypeWithNoGenericTypes(node: Node, checkMode: CheckMode | undefined) {