fix(3p/nix): Update for usage of new attribute set API r/802

The new attribute set API uses the iterators of the btree_map
directly. This requires changes in various files because the internals
of libexpr are very entangled.

This code runs and compiles, but there is a bug causing empty
attribute sets to be assigned incorrectly.

1 files changed, 2 insertions, 6 deletions

diff --git a/third_party/nix/src/libexpr/attr-set.cc b/third_party/nix/src/libexpr/attr-set.cc
index 2df6bc9a2155..a74292666b93 100644
--- a/third_party/nix/src/libexpr/attr-set.cc
+++ b/third_party/nix/src/libexpr/attr-set.cc
@@ -34,13 +34,9 @@ Bindings::iterator Bindings::find(const Symbol& name) {
   return attributes_.find(name);
 }
 
-Bindings::iterator Bindings::begin() {
-  return attributes_.begin();
-}
+Bindings::iterator Bindings::begin() { return attributes_.begin(); }
 
-Bindings::iterator Bindings::end() {
-  return attributes_.end();
-}
+Bindings::iterator Bindings::end() { return attributes_.end(); }
 
 void Bindings::merge(Bindings* other) {
   // We want the values from the other attribute set to take