From 82fd5a884dbd4d058736981635198ba27e4d656d Mon Sep 17 00:00:00 2001
From: Anders Hejlsberg <andersh@microsoft.com>
Date: Sat, 18 Nov 2017 11:42:56 -0800
Subject: [PATCH] Add test

---
 .../strictPropertyInitialization.ts               | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts b/tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts
index 9c8d56e1f5a..01177200429 100644
--- a/tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts
+++ b/tests/cases/conformance/classes/propertyMemberDeclarations/strictPropertyInitialization.ts
@@ -84,3 +84,18 @@ abstract class C9 {
     abstract c: number | null;
     abstract d?: number;
 }
+
+// Properties with non-undefined types must be assigned before they can be accessed
+// within their constructor
+
+class C10 {
+    a: number;
+    b: number;
+    c?: number;
+    constructor() {
+        let x = this.a;  // Error
+        this.a = this.b;  // Error
+        this.b = x;
+        let y = this.c;
+    }
+}