Fixes this random failure:
error: hash mismatch in fixed-output derivation '/tmp/nix-shell.EUgAVU/nix-test/tests/check/store/sfps3l3c5n7dabpx34kigxnfhmrwk2h6-dummy.drv':
specified: sha256-47DEQpj8HBSa+/TImW+5JCeuQeRkm5NMpJWZG3hSuFU=
got: sha256-0qhPS4tlCTfsj3PNi+LHSt1akRumTfJ0WO2CKdqASiY=
which happens because multiple tests were writing to ./dummy.
SHA-256 outputs of fixed-output derivations. I.e. they now produce
the same store path:
$ nix-store --add x
/nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x
$ nix-store --add-fixed --recursive sha256 x
/nix/store/j2fq9qxvvxgqymvpszhs773ncci45xsj-x
the latter being the same as the path that a derivation
derivation {
name = "x";
outputHashAlgo = "sha256";
outputHashMode = "recursive";
outputHash = "...";
...
};
produces.
This does change the output path for such fixed-output derivations.
Fortunately they are quite rare. The most common use is fetchsvn
calls with SHA-256 hashes. (There are a handful of those is
Nixpkgs, mostly unstable development packages.)
* Documented the computation of store paths (in store-api.cc).