newsflash 0 -> 1
attrpath: newsflash
Checking auto update branch...
[version] 
[version] skipping because derivation has updateScript
[rustCrateVersion] 
[rustCrateVersion] No cargoSha256 or cargoHash found
[golangModuleVersion] 
[golangModuleVersion] Not a buildGoModule package with vendorSha256 or vendorHash
[npmDepsVersion] 
[npmDepsVersion] No npmDepsHash
[updateScript] 
[updateScript] Success
[updateScript] this derivation will be built:
  /nix/store/iikaj4lvw9i2r74n021r1lpbk75ig8y1-packages.json.drv
building '/nix/store/iikaj4lvw9i2r74n021r1lpbk75ig8y1-packages.json.drv'...

Going to be running update for following packages:
 - newsflash-3.1.1

Press Enter key to continue...
Running update for:
 - newsflash-3.1.1: UPDATING ...
 - newsflash-3.1.1: DONE.

Packages updated!

Diff after rewrites:
diff --git a/pkgs/applications/networking/feedreaders/newsflash/default.nix b/pkgs/applications/networking/feedreaders/newsflash/default.nix
index de9ab81d718b..613a5e6d1ffd 100644
--- a/pkgs/applications/networking/feedreaders/newsflash/default.nix
+++ b/pkgs/applications/networking/feedreaders/newsflash/default.nix
@@ -25,13 +25,13 @@
 
 stdenv.mkDerivation (finalAttrs: {
   pname = "newsflash";
-  version = "3.1.1";
+  version = "3.1.3";
 
   src = fetchFromGitLab {
     owner = "news-flash";
     repo = "news_flash_gtk";
     rev = "refs/tags/v.${finalAttrs.version}";
-    hash = "sha256-ivdrbGtNa4/o+tXBQF9Ef17iNEUVFNPEXw1XpYxmRoQ=";
+    hash = "sha256-eaZkuFy+pDL09S8TQjpUUPIy+mFIwBScgc8hgbkRJDc=";
   };
 
   cargoDeps = rustPlatform.importCargoLock {

No auto update branch exists
Received ExitFailure 1 when running
Raw command: /nix/store/3nqhcyc7vid1npgcd0m7arg5sn325nhz-nix-2.12.0/bin/nix-build --option sandbox true --arg config "{ allowBroken = true; allowUnfree = true; allowAliases = false; }" --arg overlays "[ ]" -A newsflash
nix build failed.
> 
> [[package]]
4826,4835c4945
< version = "0.5.40"
< source = "registry+https://github.com/rust-lang/crates.io-index"
< checksum = "f593a95398737aeed53e489c785df13f3618e41dbcd6718c6addbf1395aa6876"
< dependencies = [
<  "memchr",
< ]
< 
< [[package]]
< name = "winnow"
< version = "0.6.1"
---
> version = "0.5.39"
4837c4947
< checksum = "d90f4e0f530c4c69f62b80d839e9ef3855edc9cba471a160c4d692deed62b401"
---
> checksum = "5389a154b01683d28c77f8f68f49dea75f0a4da32557a58f68ee51ebba472d29"

ERROR: cargoHash or cargoSha256 is out of date

Cargo.lock is not the same in /build/cargo-vendor-dir

To fix the issue:
1. Set cargoHash/cargoSha256 to an empty string: `cargoHash = "";`
2. Build the derivation and wait for it to fail with a hash mismatch
3. Copy the "got: sha256-..." value back into the cargoHash field
   You should have: cargoHash = "sha256-XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX=";