unikernel/duniverse/dune_/test/blackbox-tests/test-cases/dune-cache/promotion-in-source-tree.t

@@ -0,0 +1,43 @@
+Test that files promoted to the source tree are writable by the user
+
+Reproduction case for #3026
+
+  $ cat > config <<EOF
+  > (lang dune 2.1)
+  > (cache enabled)
+  > EOF
+
+  $ cat > dune-project <<EOF
+  > (lang dune 2.1)
+  > EOF
+
+  $ cat > dune <<EOF
+  > (rule
+  >  (mode promote)
+  >  (action (with-stdout-to file (echo "Hello, world!\n"))))
+  > EOF
+
+Run Dune a first time to fill the cache, then delete the promoted file and run
+Dune again. At the end of the first run, the file [_build/default/file] should
+get deduplicated and so become read-only. As a result, on the second run the
+promoted file will be copied from a read-only file. However, we still want the
+user to be able to edit this file given that it is in the source tree, so Dune
+should change the permission of this file.
+
+We check that Dune does change the permission by echoing something into the file
+after the second run.
+
+  $ env XDG_RUNTIME_DIR=$PWD/.xdg-runtime \
+  >     XDG_CACHE_HOME=$PWD/.xdg-cache \
+  >   dune build --config-file=config file
+
+  $ rm -f file
+
+  $ env XDG_RUNTIME_DIR=$PWD/.xdg-runtime \
+  >     XDG_CACHE_HOME=$PWD/.xdg-cache \
+  >   dune build --config-file=config file
+
+  $ cat file
+  Hello, world!
+
+  $ echo plop > file