capture exception on Exceptions.SetError, restore in ThrowLastAsClrException

lostmsu · lostmsu · commit d6679987886b · 2020-05-13T14:03:51.000-07:00
diff --git a/src/runtime/exceptions.cs b/src/runtime/exceptions.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Reflection;
+using System.Runtime.ExceptionServices;
 using System.Runtime.InteropServices;
 
 namespace Python.Runtime
@@ -285,6 +286,12 @@ public static void SetError(Exception e)
 
             IntPtr op = Converter.ToPython(e);
             IntPtr etype = Runtime.PyObject_GetAttrString(op, "__class__");
+#if NETSTANDARD
+            var exceptionInfo = ExceptionDispatchInfo.Capture(e);
+            Runtime.XDecref(op);
+            op = Converter.ToPython(exceptionInfo);
+#endif
+
             Runtime.PyErr_SetObject(etype, op);
             Runtime.XDecref(etype);
             Runtime.XDecref(op);
diff --git a/src/runtime/pythonexception.cs b/src/runtime/pythonexception.cs
@@ -66,26 +66,30 @@ internal static Exception ThrowLastAsClrException()
             IntPtr gs = PythonEngine.AcquireLock();
             try
             {
-                Runtime.PyErr_Fetch(out var pyTypeHandle, out var pyValueHandle, out var pyTracebackHandle);
+                Runtime.PyErr_Fetch(out var type, out var value, out var traceback);
                 try
                 {
-                    var clrObject = ManagedType.GetManagedObject(pyValueHandle) as CLRObject;
-                    if (clrObject?.inst is Exception e)
-                    {
+                    var clrObject = ManagedType.GetManagedObject(value) as CLRObject;
 #if NETSTANDARD
-                        ExceptionDispatchInfo.Capture(e).Throw();
+                    if (clrObject?.inst is ExceptionDispatchInfo storedException)
+                    {
+                        storedException.Throw();
+                        throw storedException.SourceException; // unreachable
+                    }
 #endif
+                    if (clrObject?.inst is Exception e)
+                    {
                         throw e;
                     }
 
-                    var result = FromPyErr(pyTypeHandle, pyValueHandle, pyTracebackHandle);
+                    var result = FromPyErr(type, value, traceback);
                     throw result;
                 }
                 finally
                 {
-                    pyTypeHandle.Dispose();
-                    pyValueHandle.Dispose();
-                    pyTracebackHandle.Dispose();
+                    type.Dispose();
+                    value.Dispose();
+                    traceback.Dispose();
                 }
             }
             finally
@@ -108,6 +112,13 @@ static Exception FromPyErr(BorrowedReference typeHandle, BorrowedReference value
                 return e;
             }
 
+#if NETSTANDARD
+            if (clrObject?.inst is ExceptionDispatchInfo exceptionDispatchInfo)
+            {
+                return exceptionDispatchInfo.SourceException;
+            }
+#endif
+
             var type = PyObject.FromNullableReference(typeHandle);
             var value = PyObject.FromNullableReference(valueHandle);
             var traceback = PyObject.FromNullableReference(tracebackHandle);
