unikernel/duniverse/dune_/test/blackbox-tests/test-cases/dune-cache/readonly-fs.t

@@ -0,0 +1,40 @@
+The cache can't be written if the location to where it is supposed to be
+written can't be written to.
+
+  $ cat > dune-project <<EOF
+  > (lang dune 3.17)
+  > EOF
+  $ cat >dune <<EOF
+  > (rule (with-stdout-to foo (progn)))
+  > EOF
+
+Create a directory in which we can't write to and use this as the location
+where Dune is supposed to store the cache:
+
+  $ mkdir readonly
+  $ chmod a-w readonly
+  $ export DUNE_CACHE=enabled
+  $ export DUNE_CACHE_ROOT=$(pwd)/readonly/cache-dir
+
+  $ dune build
+  Warning: Cache directories could not be created: Permission denied; disabling
+  cache
+  Hint: Make sure the directory
+  $TESTCASE_ROOT/readonly/cache-dir/temp
+  can be created
+
+Likewise, this should also happen if the location is set via XDG variables.
+
+  $ unset DUNE_CACHE_ROOT
+  $ export XDG_CACHE_HOME=$(pwd)/readonly/xdg-cache-dir
+  $ export DUNE_CONFIG__SKIP_LINE_BREAK=enabled
+
+  $ dune build 2>&1 | sed 's/created: .*;/created: $REASON:/'
+  Warning: Cache directories could not be created: $REASON: disabling cache
+  Hint: Make sure the directory $TESTCASE_ROOT/readonly/xdg-cache-dir/dune/db/temp can be created
+
+  $ export HOME=/homeless-shelter
+  $ unset XDG_CACHE_HOME
+  $ dune build 2>&1 | sed 's/created: .*;/created: $REASON:/'
+  Warning: Cache directories could not be created: $REASON: disabling cache
+  Hint: Make sure the directory /homeless-shelter/.cache/dune/db/temp can be created