feat(tvix/nix-compat): Extract to_plain_hex_string r/7560

Towards https://b.tvl.fyi/issues/264

Change-Id: Ibde971bfb6baa97b5c678d84ce1941189bc59f6f
Reviewed-on: https://cl.tvl.fyi/c/depot/+/10969
Reviewed-by: flokli <flokli@flokli.de>
Autosubmit: Peter Kolloch <info@eigenvalue.net>
Tested-by: BuildkiteCI

1 files changed, 6 insertions, 5 deletions

diff --git a/tvix/nix-compat/src/nixhash/mod.rs b/tvix/nix-compat/src/nixhash/mod.rs
index e148eb72ee..727bf77dc5 100644
--- a/tvix/nix-compat/src/nixhash/mod.rs
+++ b/tvix/nix-compat/src/nixhash/mod.rs
@@ -61,11 +61,7 @@ impl NixHash {
     /// Formats a [NixHash] in the Nix default hash format,
     /// which is the algo, followed by a colon, then the lower hex encoded digest.
     pub fn to_nix_hex_string(&self) -> String {
-        format!(
-            "{}:{}",
-            self.algo(),
-            HEXLOWER.encode(self.digest_as_bytes())
-        )
+        format!("{}:{}", self.algo(), self.to_plain_hex_string())
     }
 
     /// Formats a [NixHash] in the format that's used inside CAHash,
@@ -77,6 +73,11 @@ impl NixHash {
             nixbase32::encode(self.digest_as_bytes())
         )
     }
+
+    /// Returns the digest as a hex string -- without any algorithm prefix.
+    pub fn to_plain_hex_string(&self) -> String {
+        HEXLOWER.encode(self.digest_as_bytes())
+    }
 }
 
 impl TryFrom<(HashAlgo, &[u8])> for NixHash {