From e619de7e089eb37f3e266e80b2ec17cf536862fa Mon Sep 17 00:00:00 2001
From: Thomas Ghysels <info@thomasg.be>
Date: Sun, 3 Mar 2019 21:58:48 +0100
Subject: [PATCH] Throw descriptive error when 'subscribable' of undefined

Fix #2139
---
 src/compile/nodes/shared/Expression.ts | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/compile/nodes/shared/Expression.ts b/src/compile/nodes/shared/Expression.ts
index 0d33988fb3a2..d52a0d80de41 100644
--- a/src/compile/nodes/shared/Expression.ts
+++ b/src/compile/nodes/shared/Expression.ts
@@ -149,6 +149,13 @@ export default class Expression {
 							dependencies.add(name);
 						}
 
+						if (name[0] === '$' && !component.var_lookup.get(name.slice(1)) && name !== '$$props') {
+							component.error(node, {
+								code: `missing-store`,
+								message: `Stores must be declared`
+							});
+						}
+
 						component.add_reference(name);
 						component.warn_if_undefined(nodes[0], template_scope, true);
 					}