unikernel/duniverse/dune_/test/blackbox-tests/test-cases/action-modifying-a-dependency.t/dune

@@ -0,0 +1,9 @@
+;; This test erroneously modify one of its dependencies
+(alias
+ (name   x)
+ (deps   data (universe))
+ (action (system "\| echo hello >> data
+                 "\| # To force the mtime to change:
+                 "\| # https://github.com/ocaml/dune/pull/1359
+                 "\| touch -t 01010000 data
+                 )))

unikernel/duniverse/dune_/test/blackbox-tests/test-cases/action-modifying-a-dependency.t/dune-project

@@ -0,0 +1 @@
+(lang dune 1.0)

unikernel/duniverse/dune_/test/blackbox-tests/test-cases/action-modifying-a-dependency.t/run.t

@@ -0,0 +1,20 @@
+In this test the "x" alias depends on the file "data" but the action
+associated to "x" appends a line to "data". The expected behavior is
+an error from Dune telling the user that this is not allowed, however
+Dune currently silently ignores this.
+
+  $ echo hello > data
+  $ dune build @x
+  $ cat _build/default/data
+  hello
+  hello
+
+  $ dune build @x
+  $ cat _build/default/data
+  hello
+  hello
+
+  $ dune build @x
+  $ cat _build/default/data
+  hello
+  hello