std::shared_ptr parseQueryLegacy()

in watchman/query/parse.cpp [332:460]
107 lines of code
24 McCabe index (conditional complexity)

std::shared_ptr<Query> parseQueryLegacy(
    const std::shared_ptr<Root>& root,
    const json_ref& args,
    int start,
    uint32_t* next_arg,
    const char* clockspec,
    json_ref* expr_p) {
  bool include = true;
  bool negated = false;
  uint32_t i;
  const char* term_name = "match";
  json_ref included, excluded;
  auto query_obj = json_object();

  if (!args.isArray()) {
    throw QueryParseError("Expected an array");
  }

  for (i = start; i < json_array_size(args); i++) {
    const char* arg = json_string_value(json_array_get(args, i));
    if (!arg) {
      /* not a string value! */
      throw QueryParseError(folly::to<std::string>(
          "rule @ position ", i, " is not a string value"));
    }
  }

  for (i = start; i < json_array_size(args); i++) {
    const char* arg = json_string_value(json_array_get(args, i));
    if (!strcmp(arg, "--")) {
      i++;
      break;
    }
    if (!strcmp(arg, "-X")) {
      include = false;
      continue;
    }
    if (!strcmp(arg, "-I")) {
      include = true;
      continue;
    }
    if (!strcmp(arg, "!")) {
      negated = true;
      continue;
    }
    if (!strcmp(arg, "-P")) {
      term_name = "ipcre";
      continue;
    }
    if (!strcmp(arg, "-p")) {
      term_name = "pcre";
      continue;
    }

    // Which group are we going to file it into
    json_ref container;
    if (include) {
      if (!included) {
        included =
            json_array({typed_string_to_json("anyof", W_STRING_UNICODE)});
      }
      container = included;
    } else {
      if (!excluded) {
        excluded =
            json_array({typed_string_to_json("anyof", W_STRING_UNICODE)});
      }
      container = excluded;
    }

    auto term = json_array(
        {typed_string_to_json(term_name, W_STRING_UNICODE),
         typed_string_to_json(arg),
         typed_string_to_json("wholename", W_STRING_UNICODE)});
    if (negated) {
      term = json_array({typed_string_to_json("not", W_STRING_UNICODE), term});
    }
    json_array_append_new(container, std::move(term));

    // Reset negated flag
    negated = false;
    term_name = "match";
  }

  if (excluded) {
    excluded =
        json_array({typed_string_to_json("not", W_STRING_UNICODE), excluded});
  }

  json_ref query_array;
  if (included && excluded) {
    query_array = json_array(
        {typed_string_to_json("allof", W_STRING_UNICODE), excluded, included});
  } else if (included) {
    query_array = included;
  } else {
    query_array = excluded;
  }

  // query_array may be NULL, which means find me all files.
  // Otherwise, it is the expression we want to use.
  if (query_array) {
    json_object_set_new_nocheck(
        query_obj, "expression", std::move(query_array));
  }

  // For trigger
  if (next_arg) {
    *next_arg = i;
  }

  if (clockspec) {
    json_object_set_new_nocheck(
        query_obj, "since", typed_string_to_json(clockspec, W_STRING_UNICODE));
  }

  /* compose the query with the field list */
  auto query = parseQuery(root, query_obj);

  if (expr_p) {
    *expr_p = query_obj;
  }

  if (query) {
    w_query_legacy_field_list(&query->fieldList);
  }

  return query;
}