src: use FastStringKey for TrackV8FastApiCall

src/node_debug.cc

@@ -23,13 +23,14 @@ using v8::Number;
 using v8::Object;
 using v8::Value;
 
-thread_local std::unordered_map<std::string_view, int> v8_fast_api_call_counts;
+thread_local std::unordered_map<FastStringKey, int, FastStringKey::Hash>
+    v8_fast_api_call_counts;
 
-void TrackV8FastApiCall(std::string_view key) {
+void TrackV8FastApiCall(FastStringKey key) {
   v8_fast_api_call_counts[key]++;
 }
 
-int GetV8FastApiCallCount(std::string_view key) {
+int GetV8FastApiCallCount(FastStringKey key) {
   return v8_fast_api_call_counts[key];
 }
 
@@ -40,7 +41,8 @@ void GetV8FastApiCallCount(const FunctionCallbackInfo<Value>& args) {
     return;
   }
   Utf8Value utf8_key(env->isolate(), args[0]);
-  args.GetReturnValue().Set(GetV8FastApiCallCount(utf8_key.ToStringView()));
+  args.GetReturnValue().Set(GetV8FastApiCallCount(
+      FastStringKey::AllowDynamic(utf8_key.ToStringView())));
 }
 
 void SlowIsEven(const FunctionCallbackInfo<Value>& args) {

src/node_debug.h

@@ -3,17 +3,18 @@
 #if defined(NODE_WANT_INTERNALS) && NODE_WANT_INTERNALS
 
 #ifdef DEBUG
-#include <string_view>
+#include "util.h"
 #endif  // DEBUG
 
 namespace node {
 namespace debug {
 
 #ifdef DEBUG
-void TrackV8FastApiCall(std::string_view key);
-int GetV8FastApiCallCount(std::string_view key);
+void TrackV8FastApiCall(FastStringKey key);
+int GetV8FastApiCallCount(FastStringKey key);
 
-#define TRACK_V8_FAST_API_CALL(key) node::debug::TrackV8FastApiCall(key)
+#define TRACK_V8_FAST_API_CALL(key)                                            \
+  node::debug::TrackV8FastApiCall(FastStringKey(key))
 #else  // !DEBUG
 #define TRACK_V8_FAST_API_CALL(key)
 #endif  // DEBUG

src/util-inl.h

@@ -618,7 +618,14 @@ constexpr bool FastStringKey::operator==(const FastStringKey& other) const {
   return name_ == other.name_;
 }
 
-constexpr FastStringKey::FastStringKey(std::string_view name)
+consteval FastStringKey::FastStringKey(std::string_view name)
+    : FastStringKey(name, 0) {}
+
+constexpr FastStringKey FastStringKey::AllowDynamic(std::string_view name) {
+  return FastStringKey(name, 0);
+}
+
+constexpr FastStringKey::FastStringKey(std::string_view name, int dummy)
     : name_(name), cached_hash_(HashImpl(name)) {}
 
 constexpr std::string_view FastStringKey::as_string_view() const {

src/util.h

@@ -822,7 +822,11 @@ class PersistentToLocal {
 // computations.
 class FastStringKey {
  public:
-  constexpr explicit FastStringKey(std::string_view name);
+  // consteval ensures that the argument is a compile-time constant.
+  consteval explicit FastStringKey(std::string_view name);
+  // passing something that is not a compile-time constant needs explicit
+  // opt-in via this helper, as it defeats the purpose of FastStringKey.
+  static constexpr FastStringKey AllowDynamic(std::string_view name);
 
   struct Hash {
     constexpr size_t operator()(const FastStringKey& key) const;
@@ -832,6 +836,8 @@ class FastStringKey {
   constexpr std::string_view as_string_view() const;
 
  private:
+  constexpr explicit FastStringKey(std::string_view name, int dummy);
+
   static constexpr size_t HashImpl(std::string_view str);
 
   const std::string_view name_;