populate: build with Rust 1.71, as in nixpkgs 23.11

The program needs Rust 1.71, the oldest version its dependencies support,
which Cargo.toml states, so clippy points out what newer versions add.
The lock file is of version 3, which Cargo reads from version 1.53 on.

1 files changed, 1 insertions, 2 deletions

diff --git a/pkgs/populate/src/flake.rs b/pkgs/populate/src/flake.rs
index b6b0790..26373d4 100644
--- a/pkgs/populate/src/flake.rs
+++ b/pkgs/populate/src/flake.rs
@@ -497,8 +497,7 @@ impl<'a> Flakes<'a> {
         let fields = self.fields(sh::draw::DERIVED_STATE, false, &state_args)?;
         let malformed =
             || Failure::Message(format!("error: can't read the state of source {name}"));
-        let (head, rest) = fields.split_at_checked(4).ok_or_else(malformed)?;
-        let [original, key_file, result, target_kind] = head else {
+        let [original, key_file, result, target_kind, rest @ ..] = fields.as_slice() else {
             return Err(malformed());
         };
         let separator = rest