From efa986887e2c87705946df7f9607c0cc9de752a9 Mon Sep 17 00:00:00 2001
From: Arseniy Alekseyev <aalekseyev@janestreet.com>
Date: Fri, 2 Aug 2019 16:11:29 +0100
Subject: [PATCH] Add a test that staging area isn't used for normal [diff]

Signed-off-by: Arseniy Alekseyev <aalekseyev@janestreet.com>
---
 test/blackbox-tests/test-cases/promote/dune  |  2 ++
 test/blackbox-tests/test-cases/promote/run.t | 14 ++++++++++++++
 2 files changed, 16 insertions(+)

diff --git a/test/blackbox-tests/test-cases/promote/dune b/test/blackbox-tests/test-cases/promote/dune
index 212ab534c568..e31de1394fd6 100644
--- a/test/blackbox-tests/test-cases/promote/dune
+++ b/test/blackbox-tests/test-cases/promote/dune
@@ -4,6 +4,8 @@
  (name blah)
  (action (diff x x.gen)))
 
+(rule (with-stdout-to x.gen.copy (cat x.gen)))
+
 (rule (with-stdout-to y.gen (echo "titi")))
 
 (alias
diff --git a/test/blackbox-tests/test-cases/promote/run.t b/test/blackbox-tests/test-cases/promote/run.t
index 55e08c83dc93..133b5e6cf596 100644
--- a/test/blackbox-tests/test-cases/promote/run.t
+++ b/test/blackbox-tests/test-cases/promote/run.t
@@ -19,6 +19,20 @@ General tests
   $ cat x
   toto
 
+The correction file stays on the filesystem even after promotion and
+can be depended on by other actions.
+
+  $ cat _build/default/x.gen
+  toto
+
+  $ printf titi > x
+  $ dune build --display short @blah x.gen.copy
+  File "x", line 1, characters 0-0:
+  Error: Files _build/default/x and _build/default/x.gen differ.
+  [1]
+  $ cat _build/default/x.gen.copy
+  toto
+
 Otherwise this test fails on OSX
   $ dune clean --display short