nix/tests/shell.nix

{ inNixShell ? false }:

with import ./config.nix;

let pkgs = rec {
  setupSh = builtins.toFile "setup" ''
    export VAR_FROM_STDENV_SETUP=foo
    for pkg in $buildInputs; do
      export PATH=$PATH:$pkg/bin
    done

    # mimic behavior of stdenv for `$out` etc. for structured attrs.
    if [ -n "''${ATTRS_SH_FILE}" ]; then
      for o in "''${!outputs[@]}"; do
        eval "''${o}=''${outputs[$o]}"
        export "''${o}"
      done
    fi
  '';

  stdenv = mkDerivation {
    name = "stdenv";
    buildCommand = ''
      mkdir -p $out
      ln -s ${setupSh} $out/setup
    '';
  };

  shellDrv = mkDerivation {
    name = "shellDrv";
    builder = "/does/not/exist";
    VAR_FROM_NIX = "bar";
    TEST_inNixShell = if inNixShell then "true" else "false";
    inherit stdenv;
    outputs = ["dev" "out"];
  };

  # Used by nix-shell -p
  runCommand = name: args: buildCommand: mkDerivation (args // {
    inherit name buildCommand stdenv;
  });

  foo = runCommand "foo" {} ''
    mkdir -p $out/bin
    echo 'echo foo' > $out/bin/foo
    chmod a+rx $out/bin/foo
    ln -s ${shell} $out/bin/bash
  '';

  bar = runCommand "bar" {} ''
    mkdir -p $out/bin
    echo 'echo bar' > $out/bin/bar
    chmod a+rx $out/bin/bar
  '';

  bash = shell;

  # ruby "interpreter" that outputs "$@"
  ruby = runCommand "ruby" {} ''
    mkdir -p $out/bin
    echo 'printf %s "$*"' > $out/bin/ruby
    chmod a+rx $out/bin/ruby
  '';

  inherit pkgs;
}; in pkgs