pythonnet · filmor · Dec 18, 2020 · Dec 17, 2020 · filmor · Dec 18, 2020
diff --git a/CHANGELOG.md b/CHANGELOG.md
@@ -26,6 +26,7 @@ details about the cause of the failure
 -   BREAKING: Parameters marked with `ParameterAttributes.Out` are no longer returned in addition
     to the regular method return value (unless they are passed with `ref` or `out` keyword).
 -   BREAKING: Drop support for the long-deprecated CLR.* prefix.
+-   `PyObject` now implements `IEnumerable<PyObject>` in addition to `IEnumerable`

 ### Fixed

@@ -40,6 +41,7 @@ details about the cause of the failure
 -    Fixed a bug where indexers could not be used if they were inherited
 -    Made it possible to use `__len__` also on `ICollection<>` interface objects
 -    Made it possible to call `ToString`, `GetHashCode`, and `GetType` on inteface objects
+-    Fixed objects returned by enumerating `PyObject` being disposed too soon

 ### Removed


diff --git a/src/embed_tests/TestPyIter.cs b/src/embed_tests/TestPyIter.cs
@@ -0,0 +1,37 @@
+using System.Linq;
+using System.Text;
+
+using NUnit.Framework;
+
+using Python.Runtime;
+
+namespace Python.EmbeddingTest
+{
+    class TestPyIter
+    {
+        [OneTimeSetUp]
+        public void SetUp()
+        {
+            PythonEngine.Initialize();
+        }
+
+        [OneTimeTearDown]
+        public void Dispose()
+        {
+            PythonEngine.Shutdown();
+        }
+
+        [Test]
+        public void KeepOldObjects()
+        {
+            using (Py.GIL())
+            using (var testString = new PyString("hello world! !$%&/()=?"))
+            {
+                PyObject[] chars = testString.ToArray();
+                Assert.IsTrue(chars.Length > 1);
+                string reconstructed = string.Concat(chars.Select(c => c.As<string>()));
+                Assert.AreEqual(testString.As<string>(), reconstructed);
+            }
+        }
+    }
+}
diff --git a/src/runtime/pyiter.cs b/src/runtime/pyiter.cs
@@ -9,7 +9,7 @@ namespace Python.Runtime
    /// PY3: https://docs.python.org/3/c-api/iterator.html
    /// for details.
    /// </summary>
-    public class PyIter : PyObject, IEnumerator<object>
+    public class PyIter : PyObject, IEnumerator<PyObject>
    {
        private PyObject _current;

@@ -46,41 +46,35 @@ public static PyIter GetIter(PyObject iterable)

        protected override void Dispose(bool disposing)
        {
-            if (null != _current)
-            {
-                _current.Dispose();
-                _current = null;
-            }
+            _current = null;
            base.Dispose(disposing);
        }

        public bool MoveNext()
        {
-            // dispose of the previous object, if there was one
-            if (null != _current)
+            NewReference next = Runtime.PyIter_Next(Reference);
+            if (next.IsNull())
            {
-                _current.Dispose();
-                _current = null;
-            }
+                if (Exceptions.ErrorOccurred())
+                {
+                    throw new PythonException();
+                }

-            IntPtr next = Runtime.PyIter_Next(obj);
-            if (next == IntPtr.Zero)
-            {
+                // stop holding the previous object, if there was one
+                _current = null;
                return false;
            }

-            _current = new PyObject(next);
+            _current = next.MoveToPyObject();
            return true;
        }

        public void Reset()
        {
-            //Not supported in python.
+            throw new NotSupportedException();
        }

-        public object Current
-        {
-            get { return _current; }
-        }
+        public PyObject Current => _current;
+        object System.Collections.IEnumerator.Current => _current;
    }
 }
diff --git a/src/runtime/pyobject.cs b/src/runtime/pyobject.cs
@@ -16,7 +16,7 @@ namespace Python.Runtime
    /// for details.
    /// </summary>
    [Serializable]
-    public partial class PyObject : DynamicObject, IEnumerable, IDisposable
+    public partial class PyObject : DynamicObject, IEnumerable<PyObject>, IDisposable
    {
 #if TRACE_ALLOC
        /// <summary>
@@ -705,10 +705,11 @@ public PyObject GetIterator()
        /// python object to be iterated over in C#. A PythonException will be
        /// raised if the object is not iterable.
        /// </remarks>
-        public IEnumerator GetEnumerator()
+        public IEnumerator<PyObject> GetEnumerator()
        {
            return PyIter.GetIter(this);
        }
+        IEnumerator IEnumerable.GetEnumerator() => this.GetEnumerator();


        /// <summary>

diff --git a/src/runtime/runtime.cs b/src/runtime/runtime.cs
@@ -1854,6 +1854,8 @@ internal static bool PyIter_Check(IntPtr pointer)

        [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl)]
        internal static extern IntPtr PyIter_Next(IntPtr pointer);
+        [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl)]
+        internal static extern NewReference PyIter_Next(BorrowedReference pointer);


        //====================================================================
-Original file line number
+Diff line change
@@ -1854,6 +1854,8 @@ internal static bool PyIter_Check(IntPtr pointer)
             [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl)]
             internal static extern IntPtr PyIter_Next(IntPtr pointer);
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            filmor
  

      

      

      


        Dec 18, 2020


      
    

  


        
      
  
  
  
    

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      Do we still need this?
    
  
  



    

        
      
  
  
    
  
  
  
    
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            lostmsu
  

      

      

      


        Dec 18, 2020


      
    

  


        
      
  
  
  
    

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      Yes, there are still a few uses.
    
  
  



    

        
      
  
  
    
  
  
  
    
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+            [DllImport(_PythonDll, CallingConvention = CallingConvention.Cdecl)]
+            internal static extern NewReference PyIter_Next(BorrowedReference pointer);
             //====================================================================
-          Expand Down