Include promise status in heap snapshots

oven-sh · Jan 3, 2025 · 78cdd9b · 78cdd9b
1 parent 248e65e
commit 78cdd9b
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Showing 2 changed files with 17 additions and 3 deletions.
diff --git a/Source/JavaScriptCore/heap/BunV8HeapSnapshotBuilder.cpp b/Source/JavaScriptCore/heap/BunV8HeapSnapshotBuilder.cpp
@@ -354,7 +354,7 @@ unsigned BunV8HeapSnapshotBuilder::getNodeTypeIndex(JSCell* cell)
     return static_cast<unsigned>(V8NodeType::Native);
 }
 
-String BunV8HeapSnapshotBuilder::getDetailedNodeType(JSCell* cell)
+String BunV8HeapSnapshotBuilder::getDetailedNodeType(JSCell* cell, bool recurse)
 {
     if (!cell)
         return "(root)"_s;
@@ -420,7 +420,21 @@ String BunV8HeapSnapshotBuilder::getDetailedNodeType(JSCell* cell)
     }
 
     if (JSPromise* promise = jsDynamicCast<JSPromise*>(cell)) {
-        return "Promise"_s;
+        auto& vm = promise->globalObject()->vm();
+        switch (promise->status(vm)) {
+        case JSPromise::Status::Pending:
+            return "Promise (pending)"_s;
+        case JSPromise::Status::Fulfilled: {
+            JSValue result = promise->result(vm);
+            if (result.isCell() && recurse) {
+                // set recurse to false to make sure we don't infinitely expand promises
+                return makeString("Promise (fulfilled: "_s, getDetailedNodeType(result.asCell(), false), ")"_s);
+            }
+            return "Promise (fulfilled)"_s;
+        }
+        case JSPromise::Status::Rejected:
+            return "Promise (rejected)"_s;
+        }
     }
 
     auto* object = cell->getObject();

diff --git a/Source/JavaScriptCore/heap/BunV8HeapSnapshotBuilder.h b/Source/JavaScriptCore/heap/BunV8HeapSnapshotBuilder.h
@@ -131,7 +131,7 @@ class JS_EXPORT_PRIVATE BunV8HeapSnapshotBuilder final : public HeapAnalyzer {
     unsigned getEdgeTypeIndex(const String& type);
     unsigned addString(const String&);
     void initializeTypeNames();
-    String getDetailedNodeType(JSCell*);
+    String getDetailedNodeType(JSCell*, bool recurse = true);
     std::optional<TraceLocation> getTraceLocation(JSCell*);
 };