Method ErrorMessage

parser/parser.cc:213–244

  bool HasErrors() const { return error_count_ != 0; }

  std::string ErrorMessage() {
    // Errors are collected as they are encountered, not by their location
    // within the source. To have a more stable error message as implementation
    // details change, we sort the collected errors by their source location
    // first.
    std::stable_sort(
        errors_.begin(), errors_.end(),
        [](const ParserError& lhs, const ParserError& rhs) -> bool {
          auto lhs_begin = PositiveOrMax(lhs.range.begin);
          auto lhs_end = PositiveOrMax(lhs.range.end);
          auto rhs_begin = PositiveOrMax(rhs.range.begin);
          auto rhs_end = PositiveOrMax(rhs.range.end);
          return lhs_begin < rhs_begin ||
                 (lhs_begin == rhs_begin && lhs_end < rhs_end);
        });
    // Build the summary error message using the sorted errors.
    bool errors_truncated = error_count_ > 100;
    std::vector<std::string> messages;
    messages.reserve(
        errors_.size() +
        errors_truncated);  // Reserve space for the transform and an
                            // additional element when truncation occurs.
    std::transform(errors_.begin(), errors_.end(), std::back_inserter(messages),
                   [this](const ParserError& error) {
                     return cel::DisplayParserError(source_, error);
                   });
    if (errors_truncated) {
      messages.emplace_back(
          absl::StrCat(error_count_ - 100, " more errors were truncated."));
    }
    return absl::StrJoin(messages, "\n");
  }

  void AddMacroCall(int64_t macro_id, absl::string_view function,
                    absl::optional<Expr> target, std::vector<Expr> arguments) {