diff --git a/pkgs/build-support/rust/import-cargo-lock.nix b/pkgs/build-support/rust/import-cargo-lock.nix index 244572f79e8..83f4e0df4f2 100644 --- a/pkgs/build-support/rust/import-cargo-lock.nix +++ b/pkgs/build-support/rust/import-cargo-lock.nix @@ -63,11 +63,19 @@ let # We can't use the existing fetchCrate function, since it uses a # recursive hash of the unpacked crate. - fetchCrate = pkg: fetchurl { - name = "crate-${pkg.name}-${pkg.version}.tar.gz"; - url = "https://crates.io/api/v1/crates/${pkg.name}/${pkg.version}/download"; - sha256 = pkg.checksum; - }; + fetchCrate = pkg: + assert lib.assertMsg (pkg ? checksum) '' + Package ${pkg.name} does not have a checksum. + Please note that the Cargo.lock format where checksums used to be listed + under [metadata] is not supported. + If that is the case, running `cargo update` with a recent toolchain will + automatically update the format along with the crate's depenendencies. + ''; + fetchurl { + name = "crate-${pkg.name}-${pkg.version}.tar.gz"; + url = "https://crates.io/api/v1/crates/${pkg.name}/${pkg.version}/download"; + sha256 = pkg.checksum; + }; # Fetch and unpack a crate. mkCrate = pkg: