From ed958094f85b865d25563d8b3420d058baf99d11 Mon Sep 17 00:00:00 2001
From: Sebastian Schweizer <sebastian@schweizer.tel>
Date: Fri, 28 Dec 2018 20:40:14 +0100
Subject: [PATCH] throw Error if detector is missing

---
 src/PluginState.js | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/PluginState.js b/src/PluginState.js
index 69b0865..e0888ae 100644
--- a/src/PluginState.js
+++ b/src/PluginState.js
@@ -66,9 +66,12 @@ class PluginState {
     async getPolyfillDetector(polyfill) {
         const meta = await this._polyfillLibrary.describePolyfill(polyfill);
         if (meta) {
-            return meta.detectSource;
+            if (meta.detectSource) {
+                return meta.detectSource;
+            }
+            throw new Error(`[webpack-polyfill-injector] The polyfill ${polyfill} does not have a detector! Consider sending a PR with a suitable detect.js file to polyfill-library.`);
         }
-        throw new Error(`The polyfill ${polyfill} does not exist!`);
+        throw new Error(`[webpack-polyfill-injector] The polyfill ${polyfill} does not exist!`);
     }
 }