Rewrote it to be more compact

Author: szegedi

bindings/binding.cc

@@ -29,8 +29,8 @@
 #include <unistd.h>
 #endif
 
-// Whether the isolate's ContinuationPreservedEmbedderData currently binds
-// `key` to `value`.
+// Whether the isolate's ContinuationPreservedEmbedderData is a JS Map that
+// currently binds `key` to `value`.
 //
 // This exists for AsyncContextFrame feature detection. With ACF active, Node
 // implements AsyncLocalStorage#run by installing an AsyncContextFrame — a JS
@@ -39,57 +39,28 @@
 // store therefore observes the property this addon actually depends on,
 // instead of inferring it from the Node version, process.execArgv, or whether
 // run() happens to dispatch through the instance's enterWith.
-//
-// It is the same slot, and the same "is it a Map" question, that
-// WallProfiler::SetContext asks before storing a context, and the identity
-// hash published as otel_thread_ctx_nodejs_v1.als_identity_hash is the hash of
-// this very key — so a false answer here means both consumers are broken.
-//
-// Deliberately total: no context entered, CPED unset or not a Map, or the key
-// absent all yield false rather than throwing. The otel thread-ctx writer calls
-// this from ensureHook(), which runs inside dd-trace-js diagnostic-channel
-// subscribers, where an exception would surface in application code.
-//
-// Uses the public v8::Map::Get rather than the raw OrderedHashMap walk in
-// map-get.hh on purpose: this answers "is ACF on", and conflating it with "is
-// our map layout knowledge still correct" would report a V8 layout change as
-// ACF being unavailable. Layout is covered separately, by the GetValueFromMap
-// tests.
 static NAN_METHOD(CpedMapContains) {
 #if NODE_MAJOR_VERSION >= 22
-  auto isolate = info.GetIsolate();
-
   // A malformed call must not accidentally answer true by comparing an absent
   // key's undefined against an undefined expected value.
-  if (info.Length() < 2) {
-    info.GetReturnValue().Set(false);
-    return;
+  if (info.Length() >= 2) {
+    auto isolate = info.GetIsolate();
+    auto cped = isolate->GetContinuationPreservedEmbedderData();
+    if (!cped.IsEmpty() && cped->IsMap()) {
+      auto context = isolate->GetCurrentContext();
+      if (!context.IsEmpty()) {
+        v8::Local<v8::Value> found;
+        if (cped.As<v8::Map>()->Get(context, info[0]).ToLocal(&found)) {
+          info.GetReturnValue().Set(found->StrictEquals(info[1]));
+          return;
+        }
+      }
+    }
   }
-
-  auto context = isolate->GetCurrentContext();
-  if (context.IsEmpty()) {
-    info.GetReturnValue().Set(false);
-    return;
-  }
-
-  auto cped = isolate->GetContinuationPreservedEmbedderData();
-  if (cped.IsEmpty() || !cped->IsMap()) {
-    info.GetReturnValue().Set(false);
-    return;
-  }
-
-  v8::Local<v8::Value> found;
-  if (!cped.As<v8::Map>()->Get(context, info[0]).ToLocal(&found)) {
-    info.GetReturnValue().Set(false);
-    return;
-  }
-
-  info.GetReturnValue().Set(found->StrictEquals(info[1]));
-#else
-  // No ContinuationPreservedEmbedderData, and no AsyncContextFrame to put in
-  // it, so false is the right answer rather than a missing export.
-  info.GetReturnValue().Set(false);
 #endif
+  // Either code above didn't reach the innermost if statement, or
+  // we're compiling for Node.js < 22.
+  info.GetReturnValue().Set(false);
 }
 
 static NAN_METHOD(GetNativeThreadId) {