Method parse_assert

libbuild2/parser.cxx:6472–6528

  }

  void parser::
  parse_assert (token& t, type& tt)
  {
    bool neg (t.value.back () == '!');
    const location al (get_location (t));

    // Parse the next chunk (the condition) similar to a value on the RHS of
    // an assignment. We allow attributes (which will only apply to the
    // condition) for the same reason as in if-else (see parse_if_else()).
    //
    mode (lexer_mode::value);
    next_with_attributes (t, tt);

    const location el (get_location (t));

    try
    {
      // Should evaluate to 'true' or 'false'.
      //
      bool e (
        convert<bool> (
          parse_value_with_attributes (t, tt,
                                       pattern_mode::expand,
                                       "expression",
                                       nullptr,
                                       true /* chunk */)));
      e = (neg ? !e : e);

      if (e)
      {
        skip_line (t, tt);

        if (tt != type::eos)
          next (t, tt); // Swallow newline.

        return;
      }
    }
    catch (const invalid_argument& e) { fail (el) << e; }

    // Being here means things didn't end up well. Parse the description, if
    // any, with expansion. Then fail.
    //
    names ns (tt != type::newline && tt != type::eos
              ? parse_names (t, tt,
                             pattern_mode::ignore,
                             "description",
                             nullptr)
              : names ());

    diag_record dr (fail (al));

    if (ns.empty ())
      dr << "assertion failed";
    else
      dr << ns;
  }