From c6e5b971d6e8b57fe19ad2ea9d90f769d866863f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C3=81d=C3=A1m=20Lippai?= <adam@rigo.sk>
Date: Sun, 7 Jan 2018 11:28:24 +0100
Subject: [PATCH] fix(compiler-cli): use the oldProgram option in watch mode
 (#21364)

The performCompilation() is always called with an undefined oldProgram option (even in watch mode).
This was regression introduced in: https://github.com/angular/angular/commit/957be960d28f4f6e8df695d98e2ed117e8451f88

Partial fix, discovered in: #21361

PR Close #21364
---
 packages/compiler-cli/src/perform_watch.ts | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/packages/compiler-cli/src/perform_watch.ts b/packages/compiler-cli/src/perform_watch.ts
index 0cf9cd5edd..b2b7e2faa5 100644
--- a/packages/compiler-cli/src/perform_watch.ts
+++ b/packages/compiler-cli/src/perform_watch.ts
@@ -200,7 +200,7 @@ export function performWatchCompilation(host: PerformWatchHost):
       rootNames: cachedOptions.rootNames,
       options: cachedOptions.options,
       host: cachedCompilerHost,
-      oldProgram: cachedProgram,
+      oldProgram: oldProgram,
       emitCallback: host.createEmitCallback(cachedOptions.options)
     });