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pythonnet · lostmsu · Sep 21, 2020 · Sep 16, 2020 · Sep 18, 2020 · Sep 18, 2020
commit 945db38af4b5f53f4a454283c77d0500ab378e91
diff --git a/src/runtime/pyansistring.cs b/src/runtime/pyansistring.cs
@@ -19,7 +19,7 @@ public PyAnsiString(IntPtr ptr) : base(ptr)
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsStringType(o))
+            if (o == null || !IsStringType(o))
             {
                 throw new ArgumentException("object is not a string");
             }

diff --git a/src/runtime/pydict.cs b/src/runtime/pydict.cs
@@ -48,11 +48,11 @@ public PyDict() : base(Runtime.PyDict_New())
         /// </remarks>
         public PyDict(PyObject o) : base(o.obj)
         {
+            Runtime.XIncref(o.obj);
             if (!IsDictType(o))
             {
                 throw new ArgumentException("object is not a dict");
             }
-            Runtime.XIncref(o.obj);
         }
 
 

diff --git a/src/runtime/pyfloat.cs b/src/runtime/pyfloat.cs
@@ -47,7 +47,7 @@ public PyFloat(double value) : base(FromDouble(value))
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsFloatType(o))
+            if (o == null || !IsFloatType(o))
             {
                 throw new ArgumentException("object is not a float");
             }

diff --git a/src/runtime/pyint.cs b/src/runtime/pyint.cs
@@ -37,7 +37,7 @@ public PyInt(PyObject o) : base(FromObject(o))
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsIntType(o))
+            if (o == null || !IsIntType(o))
             {
                 throw new ArgumentException("object is not an int");
             }

diff --git a/src/runtime/pyiter.cs b/src/runtime/pyiter.cs
@@ -27,6 +27,10 @@ public PyIter(IntPtr ptr) : base(ptr)
 
         private static IntPtr FromObject(PyObject iterable)
         {
+            if (iterable == null)
+            {
+                throw new NullReferenceException();
+            }
             IntPtr val = Runtime.PyObject_GetIter(iterable.obj);
             if (val == IntPtr.Zero)
             {
@@ -35,14 +39,27 @@ private static IntPtr FromObject(PyObject iterable)
             return val;
         }
 
+
         /// <summary>
-        /// PyIter Constructor
+        /// PyIter factory function.
         /// </summary>
         /// <remarks>
-        /// Creates a Python iterator from an iterable. Like doing "iter(iterable)" in python.
+        /// Create a new PyIter from a given iterable.  Like doing "iter(iterable)" in python.
         /// </remarks>
-        public PyIter(PyObject iterable) : base(FromObject(iterable))
+        /// <param name="iterable"></param>
+        /// <returns></returns>
+        public static PyIter GetIter(PyObject iterable)
         {
+            if (iterable == null)
+            {
+                throw new NullReferenceException();
+            }
+            IntPtr val = Runtime.PyObject_GetIter(iterable.obj);
+            if (val == IntPtr.Zero)
+            {
+                throw new PythonException();
+            }
+            return new PyIter(val);
         }
 
         protected override void Dispose(bool disposing)

diff --git a/src/runtime/pylist.cs b/src/runtime/pylist.cs
@@ -30,7 +30,7 @@ internal PyList(BorrowedReference reference) : base(reference) { }
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsListType(o))
+            if (o == null || !IsListType(o))
             {
                 throw new ArgumentException("object is not a list");
             }
@@ -76,6 +76,7 @@ private static IntPtr FromArray(PyObject[] items)
                 int r = Runtime.PyList_SetItem(val, i, ptr);
                 if (r < 0)
                 {
+                    Runtime.Py_DecRef(val);
                     throw new PythonException();
                 }
             }

diff --git a/src/runtime/pylong.cs b/src/runtime/pylong.cs
@@ -37,7 +37,7 @@ public PyLong(PyObject o) : base(FromObject(o))
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsLongType(o))
+            if (o == null || !IsLongType(o))
             {
                 throw new ArgumentException("object is not a long");
             }

diff --git a/src/runtime/pyobject.cs b/src/runtime/pyobject.cs
@@ -699,7 +699,7 @@ public PyObject GetIterator()
         /// </remarks>
         public IEnumerator GetEnumerator()
         {
-            return new PyIter(this);
+            return PyIter.GetIter(this);
         }
 
 

diff --git a/src/runtime/pystring.cs b/src/runtime/pystring.cs
@@ -28,7 +28,7 @@ public PyString(IntPtr ptr) : base(ptr)
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsStringType(o))
+            if (o == null || !IsStringType(o))
             {
                 throw new ArgumentException("object is not a string");
             }

diff --git a/src/runtime/pytuple.cs b/src/runtime/pytuple.cs
@@ -33,7 +33,7 @@ internal PyTuple(BorrowedReference reference) : base(reference) { }
 
         private static IntPtr FromObject(PyObject o)
         {
-            if (!IsTupleType(o))
+            if (o == null || !IsTupleType(o))
             {
                 throw new ArgumentException("object is not a tuple");
             }