refactor: Create accepting NFA states using RAII.

src/log_surgeon/LexicalRule.hpp

@@ -41,9 +41,7 @@ class LexicalRule {
 
 template <typename TypedNfaState>
 void LexicalRule<TypedNfaState>::add_to_nfa(finite_automata::Nfa<TypedNfaState>* nfa) const {
-    auto* end_state = nfa->new_state();
-    end_state->set_accepting(true);
-    end_state->set_matching_variable_id(m_variable_id);
+    auto* end_state = nfa->new_accepting_state(m_variable_id);
     m_regex->add_to_nfa_with_negative_captures(nfa, end_state);
 }
 }  // namespace log_surgeon

src/log_surgeon/finite_automata/Nfa.hpp

@@ -43,6 +43,12 @@ class Nfa {
      */
     [[nodiscard]] auto new_state() -> TypedNfaState*;
 
+    /*
+     * @param matching_variable_id The id for the variable matched by this state.
+     * @return A pointer to the newly created accepting NFA state.
+     */
+    [[nodiscard]] auto new_accepting_state(uint32_t matching_variable_id) -> TypedNfaState*;
+
     /**
      * @param captures A vector containing the captures of all alternate paths.
      * @param dest_state The destination state to arrive at after negating the captures.
@@ -137,6 +143,13 @@ auto Nfa<TypedNfaState>::new_state() -> TypedNfaState* {
     return m_states.back().get();
 }
 
+template <typename TypedNfaState>
+auto Nfa<TypedNfaState>::new_accepting_state(uint32_t const matching_variable_id
+) -> TypedNfaState* {
+    m_states.emplace_back(std::make_unique<TypedNfaState>(matching_variable_id));
+    return m_states.back().get();
+}
+
 template <typename TypedNfaState>
 auto Nfa<TypedNfaState>::new_state_from_negative_captures(
         std::vector<Capture const*> const& captures,

src/log_surgeon/finite_automata/NfaState.hpp

@@ -37,7 +37,11 @@ class NfaState {
 public:
     using Tree = UnicodeIntervalTree<NfaState*>;
 
-    NfaState() = default;
+    explicit NfaState() {}
+
+    NfaState(uint32_t const matching_variable_id)
+            : m_accepting{true},
+              m_matching_variable_id{matching_variable_id} {}
 
     NfaState(
             TagOperationType const op_type,
@@ -47,12 +51,6 @@ class NfaState {
         add_spontaneous_transition(op_type, tag_ids, dest_state);
     }
 
-    auto set_accepting(bool const accepting) -> void { m_accepting = accepting; }
-
-    auto set_matching_variable_id(uint32_t const variable_id) -> void {
-        m_matching_variable_id = variable_id;
-    }
-
     auto add_spontaneous_transition(NfaState const* dest_state) -> void {
         m_spontaneous_transitions.emplace_back(std::vector<TagOperation>{}, dest_state);
     }