std::string Reader::Describe()

in Firestore/core/src/local/leveldb_key.cc [505:624]
101 lines of code
35 McCabe index (conditional complexity)

std::string Reader::Describe() {
  leveldb::Slice original = src_;

  bool is_terminated = false;

  std::string description;
  absl::StrAppend(&description, "[");

  while (!empty()) {
    leveldb::Slice saved_source = src_;

    ComponentLabel label = ReadComponentLabel();
    if (!ok_) {
      break;
    }
    if (label == ComponentLabel::Terminator) {
      is_terminated = true;
      break;
    }

    // Reset the reader since all the different read routines expect to see the
    // separator first
    src_ = saved_source;

    if (label == ComponentLabel::PathSegment) {
      ResourcePath resource_path = ReadResourcePath();
      if (ok_) {
        absl::StrAppend(&description,
                        " path=", resource_path.CanonicalString());
      }

    } else if (label == ComponentLabel::TableName) {
      std::string table = ReadLabeledString(ComponentLabel::TableName);
      if (ok_) {
        absl::StrAppend(&description, table, ":");
      }

    } else if (label == ComponentLabel::BatchId) {
      model::BatchId batch_id = ReadBatchId();
      if (ok_) {
        absl::StrAppend(&description, " batch_id=", batch_id);
      }

    } else if (label == ComponentLabel::CanonicalId) {
      std::string canonical_id = ReadCanonicalId();
      if (ok_) {
        absl::StrAppend(&description, " canonical_id=", canonical_id);
      }

    } else if (label == ComponentLabel::TargetId) {
      model::TargetId target_id = ReadTargetId();
      if (ok_) {
        absl::StrAppend(&description, " target_id=", target_id);
      }

    } else if (label == ComponentLabel::UserId) {
      std::string user_id = ReadUserId();
      if (ok_) {
        absl::StrAppend(&description, " user_id=", user_id);
      }

    } else if (label == ComponentLabel::CollectionId) {
      std::string collection_id = ReadCollectionId();
      if (ok_) {
        absl::StrAppend(&description, " collection_id=", collection_id);
      }

    } else if (label == ComponentLabel::DocumentId) {
      std::string document_id = ReadDocumentId();
      if (ok_) {
        absl::StrAppend(&description, " document_id=", document_id);
      }

    } else if (label == ComponentLabel::SnapshotVersion) {
      model::SnapshotVersion snapshot_version = ReadSnapshotVersion();
      if (ok_) {
        absl::StrAppend(&description,
                        " snapshot_version=", snapshot_version.ToString());
      }
    } else if (label == ComponentLabel::BundleId) {
      std::string bundle_id = ReadBundleId();
      if (ok_) {
        absl::StrAppend(&description, " bundle_id=", bundle_id);
      }
    } else if (label == ComponentLabel::QueryName) {
      std::string query_name = ReadQueryName();
      if (ok_) {
        absl::StrAppend(&description, " query_name=", query_name);
      }
    } else if (label == ComponentLabel::IndexId) {
      int32_t index_id = ReadIndexId();
      if (ok_) {
        absl::StrAppend(&description, " index_id=", index_id);
      }
    } else if (label == ComponentLabel::IndexArrayValue) {
      std::string value = ReadIndexArrayValue();
      if (ok_) {
        absl::StrAppend(&description, " array_value=", std::move(value));
      }
    } else if (label == ComponentLabel::IndexDirectionalValue) {
      std::string value = ReadIndexDirectionalValue();
      if (ok_) {
        absl::StrAppend(&description, " directional_value=", std::move(value));
      }
    } else {
      absl::StrAppend(&description, " unknown label=", static_cast<int>(label));
      Fail();
    }
  }

  if (!ok_ || !empty()) {
    absl::StrAppend(&description, " invalid key=<", InvalidKey(original), ">");

  } else if (!is_terminated) {
    absl::StrAppend(&description, " incomplete key");
  }

  absl::StrAppend(&description, "]");
  return description;
}