feat(tvix/eval): implement `inherit` in attribute set literals r/4548

Straightforward implementation, evaluating the elements of an inherit
and preparing the stack so that `OpAttrs` sees all relevant values
when constructing the attribute set itself.

The emitted instructions for inheriting a lot of values from the same
attribute set are inefficient, but it's too early to say whether this
actually matters.

Change-Id: Icb55a20936d4ef77173f34433811c5fa5d2c9ecc
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6214
Reviewed-by: grfn <grfn@gws.fyi>
Tested-by: BuildkiteCI

1 files changed, 2 insertions, 0 deletions

diff --git a/tvix/eval/src/tests/tvix_tests/eval-okay-attrs-inherit.nix b/tvix/eval/src/tests/tvix_tests/eval-okay-attrs-inherit.nix
new file mode 100644
index 000000000000..6d045643cc81
--- /dev/null
+++ b/tvix/eval/src/tests/tvix_tests/eval-okay-attrs-inherit.nix
@@ -0,0 +1,2 @@
+let a = 15;
+in { inherit a; }