From 7e698f1613cd8f861f11a90cb8156a246e356561 Mon Sep 17 00:00:00 2001
From: Rich Harris <richard.a.harris@gmail.com>
Date: Tue, 28 Aug 2018 18:06:26 -0400
Subject: [PATCH] use watchChange plugin hook to detect invalidations

---
 src/core/create_compilers.ts | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/core/create_compilers.ts b/src/core/create_compilers.ts
index 8e25432..0013a9a 100644
--- a/src/core/create_compilers.ts
+++ b/src/core/create_compilers.ts
@@ -105,6 +105,13 @@ export class RollupCompiler {
 		const mod: any = require(input);
 		delete require.cache[input];
 
+		(mod.plugins || (mod.plugins = [])).push({
+			name: 'sapper-internal',
+			watchChange: (file: string) => {
+				this._oninvalid(file);
+			}
+		});
+
 		return mod;
 	}
 
@@ -147,8 +154,6 @@ export class RollupCompiler {
 
 				case 'BUNDLE_START':
 					this._start = Date.now();
-					// TODO figure out which file changed
-					this._oninvalid('[TODO] unknown file');
 					break;
 
 				case 'BUNDLE_END':