Merge branch 'coleb-python35_dtor_exception_fix'

* coleb-python35_dtor_exception_fix:
  Add test case for Python 3.5 assertion with a pending StopIteration
  Amend python_destructor_exception runtime test
  Call PyErr_WriteUnraisable if a destructor sets a Python exception (-builtin)
  Extended zjturner's changes to encompass all function dispatch and use PyErr_WriteUnraisable to handle exceptions during __del__.
  Python - Save and restore exception state before calling destroy.

Examples/test-suite/python/Makefile.in

@@ -58,6 +58,7 @@ CPP_TEST_CASES += \
 	primitive_types \
 	python_abstractbase \
 	python_append \
+	python_destructor_exception \
 	python_director \
 	python_docstring \
 	python_nondynamic \

Examples/test-suite/python/python_destructor_exception_runme.py

@@ -0,0 +1,64 @@
+import python_destructor_exception
+from StringIO import StringIO
+import sys
+
+def error_function():
+    python_destructor_exception.ClassWithThrowingDestructor().GetBlah()
+
+def runtest():
+    attributeErrorOccurred = False
+    try:
+        error_function()
+    except AttributeError, e:
+        attributeErrorOccurred = True
+    return attributeErrorOccurred
+
+def test1():
+    stderr_saved = sys.stderr
+    buffer = StringIO()
+    attributeErrorOccurred = False
+    try:
+        # Suppress stderr while making this call to suppress the output shown by PyErr_WriteUnraisable
+        sys.stderr = buffer
+
+        attributeErrorOccurred = runtest()
+    finally:
+        sys.stderr.flush()
+        sys.stderr = stderr_saved
+
+    assert attributeErrorOccurred
+    assert buffer.getvalue().count("I am the ClassWithThrowingDestructor dtor doing bad things") >= 1
+
+class VectorHolder(object):
+    def __init__(self, v):
+        self.v = v
+    def gen(self):
+        for e in self.v:
+            yield e
+
+# See issue #559, #560, #573 - In Python 3.5, test2() call to the generator 'gen' was
+# resulting in the following (not for -builtin where there is no call to SWIG_Python_CallFunctor
+# as SwigPyObject_dealloc is not used):
+#
+# StopIteration
+#
+# During handling of the above exception, another exception occurred:
+# ...
+# SystemError: <built-in function delete_VectorInt> returned a result with an error set
+
+def addup():
+    sum = 0
+    for i in VectorHolder(python_destructor_exception.VectorInt([1, 2, 3])).gen():
+        sum = sum + i
+    return sum
+
+def test2():
+    sum = addup()
+
+    if sum != 6:
+        raise RuntimeError("Sum is incorrect")
+
+# These two tests are different are two different ways to recreate essentially the same problem
+# reported by Python 3.5 that an exception was already set when destroying a wrapped object
+test1()
+test2()