message: we should be using absl spans
diff: @@ -105,38 +105,38 @@ bool TestRootContext::onConfigure(size_t) {
  if (test_ == "property") {
  {
  // Many properties are not available in the root context.
  - const std::vector<std::initializer_list<std::string_view>> properties = {
  - {"string_state"},
  - {"metadata"},
  - {"request"},
  - {"response"},
  - {"connection"},
  - {"connection_id"},
  - {"upstream"},
  - {"source"},
  - {"destination"},
  - {"cluster_name"},
  - {"cluster_metadata"},
  - {"route_name"},
  - {"route_metadata"},
  + const std::vector<std::string> properties = {
  + "string_state",
  + "metadata",
  + "request",
  + "response",
  + "connection",
  + "connection_id",
  + "upstream",
  + "source",
  + "destination",
  + "cluster_name",
  + "cluster_metadata",
  + "route_name",
  + "route_metadata",
  };
  for (const auto& property : properties) {
  - if (getProperty(property).has_value()) {
  + if (getProperty({property}).has_value()) {
  logWarn("getProperty should not return a value in the root context");
  }
  }
  }
  {
  // Some properties are defined in the root context.
  - std::vector<std::pair<std::initializer_list<std::string_view>, std::string> > properties = {
  - {{"plugin_name"}, "plugin_name"},
  - {{"plugin_vm_id"}, "vm_id"},
  - {{"listener_direction"}, std::string("\x1\0\0\0\0\0\0\0", 8)}, // INBOUND
  - {{"listener_metadata"}, ""},
  + std::vector<std::pair<std::string, std::string> > properties = {
  + {"plugin_name", "plugin_name"},
  + {"plugin_vm_id", "vm_id"},
  + {"listener_direction", std::string("\x1\0\0\0\0\0\0\0", 8)}, // INBOUND
  + {"listener_metadata", ""},
  };
  for (const auto& property : properties) {
  std::string value;
  - if (!getValue(property.first, &value)) {
  + if (!getValue({property.first}, &value)) {
  logWarn("getValue should provide a value in the root context: " + property.second);
  }
  if (value != property.second) {
  @@ -690,14 +690,13 @@ void TestContext::onLog() {
  }
  {
  // Some properties are not available in the stream context.
  - const std::vector<std::initializer_list<std::string_view>> properties = {
  - {"xxx"},
  - {"request", "xxx"},
  - {"route_name", "xxx"},
  - {"node", "metadata", "xxx"},
  - };
  + const std::vector<std::string> properties = {
  + "xxx",
  + "request",
  + "route_name",
  + "node"};
  for (const auto& property : properties) {
  - if (getProperty(property).has_value()) {
  + if (getProperty({property, "xxx"}).has_value()) {
  logWarn("getProperty should not return a value in the root context");
  }
  }
  