From fe49c5d923a85b7d9ae97f3a9cddee1e925ffa07 Mon Sep 17 00:00:00 2001
From: Jake Bailey <5341706+jakebailey@users.noreply.github.com>
Date: Thu, 29 Oct 2026 16:17:15 -0700
Subject: [PATCH] Reject non-access targets early when matching access
 references

Co-authored-by: Steven Chong <25894545+teamchong@users.noreply.github.com>
---
 tsc/internal/checker/flow.go | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/tsc/internal/checker/flow.go b/tsc/internal/checker/flow.go
index d2831231772fe..6193c10b2f222 100644
--- a/tsc/internal/checker/flow.go
+++ b/tsc/internal/checker/flow.go
@@ -1619,11 +1619,12 @@ func (c *Checker) isMatchingReference(source *ast.Node, target *ast.Node) bool {
 	case ast.KindNonNullExpression, ast.KindParenthesizedExpression, ast.KindSatisfiesExpression:
 		return c.isMatchingReference(source.Expression(), target)
 	case ast.KindPropertyAccessExpression, ast.KindElementAccessExpression:
+		if !ast.IsAccessExpression(target) {
+			return false
+		}
 		if sourcePropertyName, ok := c.getAccessedPropertyName(source); ok {
-			if ast.IsAccessExpression(target) {
-				if targetPropertyName, ok := c.getAccessedPropertyName(target); ok {
-					return targetPropertyName == sourcePropertyName && c.isMatchingReference(source.Expression(), target.Expression())
-				}
+			if targetPropertyName, ok := c.getAccessedPropertyName(target); ok {
+				return targetPropertyName == sourcePropertyName && c.isMatchingReference(source.Expression(), target.Expression())
 			}
 		}
 		if ast.IsElementAccessExpression(source) && ast.IsElementAccessExpression(target) {