devenv fails to exclude files with nix-filter

[smunix]

Describe the bug

devenv doesn't honor instructions to exclude files using nix-filter.

See the complete description of the bug here

To Reproduce

Get the file sources

Clone this small repository devenv-issue-01:

> git clone https://github.com/smunix/devenv-issue-01
Cloning into 'devenv-issue-01'...
remote: Enumerating objects: 15, done.
remote: Counting objects: 100% (15/15), done.
remote: Compressing objects: 100% (12/12), done.
remote: Total 15 (delta 1), reused 12 (delta 1), pack-reused 0
Receiving objects: 100% (15/15), 5.48 KiB | 5.48 MiB/s, done.
Resolving deltas: 100% (1/1), done.

cd into devenv-issue-01:

> cd devenv-issue-01 
> ls
README.md	devenv.lock	devenv.yaml	flake.nix
Top.hs		devenv.nix	flake.lock	package.yaml

Our devenv.nix requests excluding the package.yaml file, so to force callCabal2nix to fail:

> cat devenv.nix

{ pkgs, inputs, ... }:
let
  hpkgs = pkgs.haskellPackages;
  Top = with pkgs.haskell.lib;
    with hpkgs;
    with inputs;
    callCabal2nix "Top" (nix-filter.lib.filter {
      root = self;
      exclude = [ "package.yaml" ];
    }) { };
in {
  env.name = "bug.01";
  env.GREET = "bug.01";
  packages = [ Top ];
  scripts.hello.exec = "echo hello from $GREET";
  enterShell = ''
    hello
  '';
}

Building

Build with devenv

Run devenv and see it build successfully (this is bogus):

> devenv shell Top
Building shell ...
warning: Git tree '/Users/smunix/programming/repros/devenv-issue-01' is dirty
warning: applying 'toString' to path '/Users/smunix/programming/repros/devenv-issue-01/package.yaml' and then accessing it is deprecated, at «github:numtide/nix-filter/1a3b735e13e90a8d2fd5629f2f8363bd7ffbbec7»/default.nix:164:7
warning: applying 'toString' to path '/Users/smunix/programming/repros/devenv-issue-01/' and then accessing it is deprecated, at «github:numtide/nix-filter/1a3b735e13e90a8d2fd5629f2f8363bd7ffbbec7»/default.nix:165:8
hello from bug.01
"devenv sits at the Top"

Build with flake

Run the build using flake and see it fail to build (this is expected):

> nix develop -c Top
error: builder for '/nix/store/grydafb37p8qkk575g14b1z0m4gn6w7j-cabal2nix-Top.drv' failed with exit code 1;
       last 1 log lines:
       > cabal2nix: user error (*** Found neither a .cabal file nor package.yaml. Exiting.)
       For full logs, run 'nix log /nix/store/grydafb37p8qkk575g14b1z0m4gn6w7j-cabal2nix-Top.drv'.
(use '--show-trace' to show detailed location information)

The flake.nix also requested to exclude the package.yaml file, so the build failure is expected:

> cat flake.nix

{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-22.11";
    devenv.url = "github:cachix/devenv";
    nix-filter.url = "github:numtide/nix-filter";
  };

  outputs = { self, nixpkgs, devenv, ... } @ inputs:
    let
      systems = [ "x86_64-linux" "i686-linux" "x86_64-darwin" "aarch64-linux" "aarch64-darwin" ];
      forAllSystems = f: builtins.listToAttrs (map (name: { inherit name; value = f name; }) systems);
    in
    {
      devShells = forAllSystems
        (system:
          let
            pkgs = import nixpkgs {
              inherit system;
            };
            hpkgs = pkgs.haskellPackages;
            Top = with pkgs.haskell.lib;
              with hpkgs;
              with inputs;
              callCabal2nix "Top" (nix-filter.lib.filter {
                root = self;
                exclude = [ "package.yaml" ];
              }) { };
          in
          {
            default = devenv.lib.mkShell {
              inherit inputs pkgs;
              modules = [
                {
                  env.name = "bug.01";
                  env.GREET = "bug.01";
                  packages = [ Top ];
                  scripts.hello.exec = "echo hello from $GREET";
                  enterShell = ''
                    hello
                  '';
                }
              ];
            };
          });
    };
}

Version

> devenv version
devenv: 0.5

[domenkozar]

This seems to be the current limitation of lazy-trees Nix branch that we're using. See NixOS/nix#6530 for updates

[smunix]

This seems to be the current limitation of lazy-trees Nix branch that we're using. See NixOS/nix#6530 for updates

Correct, @DavHau explains the issue here