callCabal2nix is failing

[PierreR]

Issue description

haskell callCabal2nix is failing with :

error: string ‘/nix/store/3ibw2qzxknyjd30zlw0l5yikwla6yivr-language-puppet-22d8fb4ee0ad833ca2f0790e3c473e7e49424232-src’ cannot refer to other paths, at /home/vagrant/projects/cicd/nixpkgs/pkgs/development/haskell-modules/default.nix:92:25
(use ‘--show-trace’ to show detailed location information)

Steps to reproduce

Use this command line:
→ nix-shell release.nix -I nixpkgs=/home/vagrant/projects/cicd/nixpkgs

Using the following release.nix file:

with import <nixpkgs> { };
let
  language-puppet_git = pkgs.haskellPackages.callCabal2nix "language-puppet" (pkgs.fetchFromGitHub {
    owner  = "bartavelle";
    repo   = "language-puppet";
    rev    = "22d8fb4ee0ad833ca2f0790e3c473e7e49424232";
    sha256 = "1llzhf48r30qnanaay6r6mdvq4pw0ba200pl0pfagfg2kja54a9v";
  }) {};
  henv = pkgs.haskellPackages.ghcWithPackages (p: with p; [language-puppet_git ]);
in
pkgs.stdenv.mkDerivation {
  name = "build-env";
  buildInputs = [ henv ];
}

nixpkgs is pointing to the current master at c2b9b80

But I would guest it is failing from #23880

Technical details

• System: nixos 17.03beta582.1e8c017
• Nix version: nix-env (Nix) 1.11.8
• Nixpkgs version: already failing in:

{
  "url": "https://github.com/NixOS/nixpkgs.git",
  "rev": "fff8cc79df5aa26e935f8ee30c06ef79368ad5dc",
  "date": "2017-03-20T19:03:20+01:00",
  "sha256": "0jlnx75zri3gblzxb0jibllqclki0ykwn8d9zsp5p8yzyvn70j44",
  "fetchSubmodules": true
}

[globin]

cc @peti

[PierreR]

@ElvishJerricco @3noch Using git bisect I can confirm that the issue is related to:

→ git bisect bad 
24b47526ce38e3ccb073c776b32c0ea220f3c0f2 is the first bad commit
commit 24b47526ce38e3ccb073c776b32c0ea220f3c0f2
Author: Will Fancher <elvishjerricco@gmail.com>
Date:   Mon Mar 13 22:17:29 2017 -0400

    callCabal2nix: Don't rebuild unchanged cabal file
    
    It can be quite annoying that callCabal2nix will build a new derivation
    if anything in the source has changed, even if the cabal file hasn't.

[domenkozar]

afaik it happens if you pass a string instead of a path to builtins.filterSource, but here it appears to be a path returned by fetchFromGitHub? Confusing.

[PierreR]

@domenkozar I have just experienced another anomalie that might be related (?)

If I try to use language-puppet_1_3_7 from hackage-packages.nix, it will work when using:

with import (fetchTarball https://github.com/NixOS/nixpkgs/archive/fff8cc79df5aa26e935f8ee30c06ef79368ad5dc.tar.gz) {};

let
  hpkgs = pkgs.haskellPackages;
  henv = hpkgs.ghcWithPackages (p: with p; [shake language-puppet_1_3_7 foldl]);
in
stdenv.mkDerivation {
  name = "build-env";
  buildInputs = [ henv puppet-env];
}

but when I use fetchFromGitHub instead :

let
  _pkgs = import <nixpkgs> { };
  src = _pkgs.fetchFromGitHub {
    owner = "NixOS";
    repo  = "nixpkgs";
    rev   = "fff8cc79df5aa26e935f8ee30c06ef79368ad5dc";
    sha256 = "0jlnx75zri3gblzxb0jibllqclki0ykwn8d9zsp5p8yzyvn70j44";
  };

  pkgs = import src { };
  hpkgs = pkgs.haskellPackages;
  henv = hpkgs.ghcWithPackages (p: with p; [shake language-puppet_1_3_7 foldl]);
in
pkgs.stdenv.mkDerivation {
  name = "build-env";
  buildInputs = [ henv];
}

then I goes forever doing

trying http://hackage.haskell.org/package/language-puppet-1.3.7.tar.gz
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
  0     0    0     0    0     0      0      0 --:--:-- --:--:-- --:--:--     0
  0     0    0     0    0     0      0      0 --:--:--  0:06:42 --:--:--     0^Cerror: interrupted by the user

The hackage link from the hackage web site is actually
http://hackage.haskell.org/package/language-puppet-1.3.7/language-puppet-1.3.7.tar.gz (and it does work)
If this is another bug I will open a new issue.

[peti]

I reverted #23880 in 50cce50 to un-break the function.

[domenkozar]

@shlevy is this addressed by NixOS/nix#1358?

[peti]

I suppose we can close this issue? @PierreR?

[shlevy]

@domenkozar No, the error you get in that case is different, something about a bad archive format.

[domenkozar]

I'm closing this as issue has been fixed.