Add TreeInfo::computeStorePath()

src/libexpr/flake/lockfile.cc

@@ -111,8 +111,7 @@ nlohmann::json LockedInput::toJson() const
 
 StorePath LockedInput::computeStorePath(Store & store) const
 {
-    assert(info.narHash);
-    return store.makeFixedOutputPath(true, info.narHash, "source");
+    return info.computeStorePath(store);
 }
 
 LockedInputs::LockedInputs(const nlohmann::json & json)

src/libexpr/flake/lockfile.hh

@@ -11,6 +11,8 @@ struct StorePath;
 
 namespace nix::flake {
 
+using namespace fetchers;
+
 typedef std::vector<FlakeId> InputPath;
 
 struct LockedInput;