{
  lib,
  inputs,
  config,
  ...
}:
let
  den.lib = inputs.target.lib { inherit inputs lib config; };
  takes = den.lib.canTake;

  flake.tests."test exactly fails" = {
    expr = takes.exactly {
      a = 1;
      b = 2;
    } ({ a }: a);
    expected = false;
  };

  flake.tests."test exactly succeeds" = {
    expr = takes.exactly { a = 1; } ({ a }: a);
    expected = true;
  };

  flake.tests."test function with no named arguments can take anything" = {
    expr = takes { } (x: x);
    expected = true;
  };

  flake.tests."test function called with non attrs" = {
    expr = takes 22 ({ host }: [ host ]);
    expected = false;
  };

  flake.tests."test function missing required attr" = {
    expr = takes { } ({ host }: [ host ]);
    expected = false;
  };

  flake.tests."test function satisfied required attr" = {
    expr = takes {
      host = 1;
    } ({ host, ... }: [ host ]);
    expected = true;
  };

  flake.tests."test function missing second required attr" = {
    expr =
      takes
        {
          host = 1;
        }
        (
          { host, user }:
          [
            host
            user
          ]
        );
    expected = false;
  };

  flake.tests."test function optional second attr" = {
    expr =
      takes
        {
          host = 1;
          foo = 9;
        }
        (
          {
            host,
            user ? 0,
          }:
          [
            host
            user
          ]
        );
    expected = true;
  };

in
{
  inherit flake;
}