From cb8071acd456e916b46bb42916383f3f0a8a0c4e Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Sat, 24 Feb 2018 13:08:28 -0500
Subject: [PATCH] allow observing $foo in dev mode - #1181

---
 src/shared/index.js                           |  2 +-
 .../samples/store-observe-dollar/_config.js   | 25 +++++++++++++++++++
 .../samples/store-observe-dollar/main.html    |  1 +
 3 files changed, 27 insertions(+), 1 deletion(-)
 create mode 100644 test/runtime/samples/store-observe-dollar/_config.js
 create mode 100644 test/runtime/samples/store-observe-dollar/main.html

diff --git a/src/shared/index.js b/src/shared/index.js
index cf953e4bf1..d9d6475e64 100644
--- a/src/shared/index.js
+++ b/src/shared/index.js
@@ -100,7 +100,7 @@ export function observe(key, callback, options) {
 }
 
 export function observeDev(key, callback, options) {
-	var c = (key = '' + key).search(/[^\w]/);
+	var c = (key = '' + key).search(/[.[]/);
 	if (c > -1) {
 		var message =
 			'The first argument to component.observe(...) must be the name of a top-level property';
diff --git a/test/runtime/samples/store-observe-dollar/_config.js b/test/runtime/samples/store-observe-dollar/_config.js
new file mode 100644
index 0000000000..1861b937d9
--- /dev/null
+++ b/test/runtime/samples/store-observe-dollar/_config.js
@@ -0,0 +1,25 @@
+import { Store } from '../../../../store.js';
+
+const store = new Store({
+	name: 'world'
+});
+
+export default {
+	store,
+
+	html: `<h1>Hello world!</h1>`,
+
+	dev: true,
+
+	test(assert, component) {
+		const names = [];
+
+		component.observe('$name', name => {
+			names.push(name);
+		});
+
+		store.set({ name: 'everybody' });
+
+		assert.deepEqual(names, ['world', 'everybody']);
+	}
+};
\ No newline at end of file
diff --git a/test/runtime/samples/store-observe-dollar/main.html b/test/runtime/samples/store-observe-dollar/main.html
new file mode 100644
index 0000000000..28154934b8
--- /dev/null
+++ b/test/runtime/samples/store-observe-dollar/main.html
@@ -0,0 +1 @@
+<h1>Hello {{$name}}!</h1>
\ No newline at end of file