// Implementation details.

// Properties that we match on for a particular Node.  If a particular property
// is nullopt then any value for it is allowed.
class NodeMatcherProperties {
 public:
  using NodeSeqMatcher = std::vector<::testing::Matcher<const Node*>>;
  using InputSeqMatcher = std::vector<::testing::Matcher<OutEdge>>;
  using AttrKeyValuePair = std::pair<string, std::optional<AttrValue>>;