From 8c40d69d88aada23142291cb14ced7b9667939ff Mon Sep 17 00:00:00 2001
From: Conduitry <git@chor.date>
Date: Tue, 12 Nov 2019 20:03:34 -0500
Subject: [PATCH] use IE-compatible js to check for unknown prop warnings
 (#3914)

---
 src/compiler/compile/render_dom/index.ts | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/compiler/compile/render_dom/index.ts b/src/compiler/compile/render_dom/index.ts
index 49ce17236a..cc0c7dfe31 100644
--- a/src/compiler/compile/render_dom/index.ts
+++ b/src/compiler/compile/render_dom/index.ts
@@ -247,7 +247,7 @@ export default function dom(
 			function create_fragment(#ctx) {
 				${block.get_contents()}
 			}
-		`);	
+		`);
 	}
 
 	body.push(b`
@@ -369,7 +369,7 @@ export default function dom(
 			unknown_props_check = b`
 				const writable_props = [${writable_props.map(prop => x`'${prop.export_name}'`)}];
 				@_Object.keys($$props).forEach(key => {
-					if (!writable_props.includes(key) && !key.startsWith('$$')) @_console.warn(\`<${component.tag}> was created with unknown prop '\${key}'\`);
+					if (!~writable_props.indexOf(key) && key.slice(0, 2) !== '$$') @_console.warn(\`<${component.tag}> was created with unknown prop '\${key}'\`);
 				});
 			`;
 		}