{
  programs.git = {
    enable = true;
    signing.signer = "path-to-gpg";
    extraConfig = ''
      This can be anything.
    '';
    userEmail = "user@example.org";
    userName = "John Doe";
  };

  test.asserts.warnings.expected = [''
    Using programs.git.extraConfig as a string option is
    deprecated and will be removed in the future. Please
    change to using it as an attribute set instead.
  ''];

  nmt.script = ''
    assertFileExists home-files/.config/git/config
    assertFileContent home-files/.config/git/config \
      ${./git-with-str-extra-config-expected.conf}
  '';
}