Add a test for a flake referencing a flake that has inputs.self

tests/functional/flakes/flake-in-submodule.sh

@@ -27,6 +27,7 @@ git config --global protocol.file.allow always
 
 rootRepo=$TEST_ROOT/rootRepo
 subRepo=$TEST_ROOT/submodule
+otherRepo=$TEST_ROOT/otherRepo
 
 
 createGitRepo "$subRepo"
@@ -91,6 +92,33 @@ git -C "$rootRepo" commit -a -m "Bla"
 storePath=$(nix eval --raw "$rootRepo#foo")
 [[ -e "$storePath/submodule" ]]
 
+
+# Test another repo referring to a repo that uses inputs.self.
+createGitRepo "$otherRepo"
+cat > "$otherRepo"/flake.nix <<EOF
+{
+  inputs.root.url = "git+file://$rootRepo";
+  outputs = { self, root }: {
+    foo = root.foo;
+  };
+}
+EOF
+git -C "$otherRepo" add flake.nix
+
+# The first call should refetch the root repo...
+expectStderr 0 nix eval --raw "$otherRepo#foo" -vvvvv | grepQuiet "refetching"
+
+[[ $(jq .nodes.root_2.locked.submodules "$otherRepo/flake.lock") == true ]]
+
+# ... but the second call should have 'submodules = true' in flake.lock, so it should not refetch.
+rm -rf "$TEST_HOME/.cache"
+clearStore
+expectStderr 0 nix eval --raw "$otherRepo#foo" -vvvvv | grepQuietInverse "refetching"
+
+storePath=$(nix eval --raw "$otherRepo#foo")
+[[ -e "$storePath/submodule" ]]
+
+
 # The root repo may use the submodule repo as an input
 # through the relative path. This may change in the future;
 # see: https://discourse.nixos.org/t/57783 and #9708.