From b00e6b51a228e15b740b0e24dcd1558fe1727c53 Mon Sep 17 00:00:00 2001
From: Andrew Branch <andrew@wheream.io>
Date: Thu, 12 May 2022 09:39:19 -0700
Subject: [PATCH] =?UTF-8?q?Don=E2=80=99t=20widen=20literals=20based=20on?=
 =?UTF-8?q?=20bogus=20contextual=20type=20instantiation?=
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---
 src/compiler/checker.ts | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/src/compiler/checker.ts b/src/compiler/checker.ts
index daa45f35d76..350bff0aa8a 100644
--- a/src/compiler/checker.ts
+++ b/src/compiler/checker.ts
@@ -21248,8 +21248,8 @@ namespace ts {
                 type;
         }
 
-        function getWidenedLiteralLikeTypeForContextualType(type: Type, contextualType: Type | undefined) {
-            if (!isLiteralOfContextualType(type, contextualType)) {
+        function getWidenedLiteralLikeTypeForContextualType(type: Type, contextualType: Type | undefined, contextNode?: Node) {
+            if (!isLiteralOfContextualType(type, contextualType) && !(contextNode && isLiteralOfContextualType(type, instantiateContextualType(contextualType, contextNode)))) {
                 type = getWidenedUniqueESSymbolType(getWidenedLiteralType(type));
             }
             return type;
@@ -34495,7 +34495,7 @@ namespace ts {
             const type = checkExpression(node, checkMode, forceTuple);
             return isConstContext(node) || isCommonJsExportedExpression(node) ? getRegularTypeOfLiteralType(type) :
                 isTypeAssertion(node) ? type :
-                getWidenedLiteralLikeTypeForContextualType(type, instantiateContextualType(arguments.length === 2 ? getContextualType(node) : contextualType, node));
+                getWidenedLiteralLikeTypeForContextualType(type, arguments.length === 2 ? getContextualType(node) : contextualType, node);
         }
 
         function checkPropertyAssignment(node: PropertyAssignment, checkMode?: CheckMode): Type {