refactor(nix-compat/store_path): make StorePath generic on S r/8545

Similar to how cl/12253 already did this for `Signature`, we apply the
same logic to `StorePath`.

`StorePathRef<'a>'` is now a `StorePath<&'a str>`, and there's less
redundant code for the two different implementation.

`.as_ref()` returns a `StorePathRef<'_>`, `.to_owned()` gives a
`StorePath<String>` (for now).

I briefly thought about only publicly exporting `StorePath<String>`
as `StorePath`, but the diff is not too large and this will make it
easier to gradually introduce more flexibility in which store paths to
accept.

Also, remove some silliness in `StorePath::from_absolute_path_full`,
which now doesn't allocate anymore.

Change-Id: Ife8843857a1a0a3a99177ca997649fd45b8198e6
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12258
Autosubmit: flokli <flokli@flokli.de>
Tested-by: BuildkiteCI
Reviewed-by: Connor Brewster <cbrewster@hey.com>

2 files changed, 11 insertions, 11 deletions

diff --git a/tvix/glue/src/builtins/derivation.rs b/tvix/glue/src/builtins/derivation.rs
index 6a61b0dbaf36..5bc9dab71283 100644
--- a/tvix/glue/src/builtins/derivation.rs
+++ b/tvix/glue/src/builtins/derivation.rs
@@ -568,7 +568,7 @@ pub(crate) mod derivation_builtins {
             let blob_digest = blob_writer.close().await?;
             let ca_hash = CAHash::Text(Sha256::digest(&content).into());
 
-            let store_path =
+            let store_path: StorePathRef =
                 build_ca_path(name.to_str()?, &ca_hash, content.iter_ctx_plain(), false)
                     .map_err(|_e| {
                         nix_compat::derivation::DerivationError::InvalidOutputName(
diff --git a/tvix/glue/src/builtins/import.rs b/tvix/glue/src/builtins/import.rs
index 3660f575c843..34ae2778ecdd 100644
--- a/tvix/glue/src/builtins/import.rs
+++ b/tvix/glue/src/builtins/import.rs
@@ -112,7 +112,7 @@ mod import_builtins {
 
     use crate::tvix_store_io::TvixStoreIO;
     use nix_compat::nixhash::{CAHash, NixHash};
-    use nix_compat::store_path::StorePath;
+    use nix_compat::store_path::StorePathRef;
     use sha2::Digest;
     use tokio::io::AsyncWriteExt;
     use tvix_eval::builtins::coerce_value_to_path;
@@ -377,16 +377,16 @@ mod import_builtins {
             }
         })?;
 
-        let path_exists = if let Ok((store_path, sub_path)) = StorePath::from_absolute_path_full(p)
-        {
-            if !sub_path.as_os_str().is_empty() {
-                false
+        let path_exists =
+            if let Ok((store_path, sub_path)) = StorePathRef::from_absolute_path_full(p) {
+                if !sub_path.as_os_str().is_empty() {
+                    false
+                } else {
+                    state.store_path_exists(store_path.as_ref()).await?
+                }
             } else {
-                state.store_path_exists(store_path.as_ref()).await?
-            }
-        } else {
-            false
-        };
+                false
+            };
 
         if !path_exists {
             return Err(ImportError::PathNotInStore(p.into()).into());