Merge pull request #4969 from serokell/balsoft/fix-nixConfig-flake-registry

flake.nixConfig: fix flake-registry config settings

src/libexpr/flake/flake.cc

@@ -298,6 +298,11 @@ LockedFlake lockFlake(
 
     auto flake = getFlake(state, topRef, lockFlags.useRegistries, flakeCache);
 
+    if (lockFlags.applyNixConfig) {
+        flake.config.apply();
+        // FIXME: send new config to the daemon.
+    }
+
     try {
 
         // FIXME: symlink attack

src/libexpr/flake/flake.hh

@@ -104,6 +104,10 @@ struct LockFlags
        references like 'nixpkgs'. */
     bool useRegistries = true;
 
+    /* Whether to apply flake's nixConfig attribute to the configuration */
+
+    bool applyNixConfig = false;
+
     /* Whether mutable flake references (i.e. those without a Git
        revision or similar) without a corresponding lock are
        allowed. Mutable flake references with a lock are always