Resolution for issue #5092: Unit test handle checks consider dangling handles to be valid.

runtime/include/dart_api.h

Index: runtime/include/dart_api.h
diff --git a/runtime/include/dart_api.h b/runtime/include/dart_api.h
index 7bd749c38e0def7732033b4d1ec13ea5e4e7ded1..7efe945cab7b95d4874646d080a6ef09b2dc9bb4 100644
--- a/runtime/include/dart_api.h
+++ b/runtime/include/dart_api.h
@@ -259,6 +259,13 @@ typedef void (*Dart_WeakPersistentHandleFinalizer)(
 typedef void (*Dart_PeerFinalizer)(void* peer);
 
 /**
+ * Is this handle valid, or has it been freed?
+ *
+ * Requires there to be a current isolate.
+ */
+DART_EXPORT bool Dart_IsValid(Dart_Handle handle);

[siva, 2017/01/18 23:27:06]

Why do we need this new API call, the issue you are addressing seems to only
talk about the EXPECT macros which are all internal to the VM

[bkonyi, 2017/01/19 01:05:13]

I was following the pattern of Dart_IsError so just assumed that there should be
a Dart_IsValid as well. I've removed it.

+
+/**
  * Is this an error handle?
  *
  * Requires there to be a current isolate.