python: Handle slight differences between Python 2 and 3.

* lang/python/helpers.c (pyDataWriteCb): Handle Python integers being
returned on Python 2.
(pyDataSeekCb): Likewise.
* lang/python/pyme/core.py (Data.__init__): Fix testing for string
argument.
(Data.new_from_filepart): Likewise.
* lang/python/pyme/util.py (is_a_string): New function.
* lang/python/tests/t-encrypt-large.py (read_cb): Force evaluation of
generator.
* lang/python/tests/t-idiomatic.py: Partly skip test on Python 2.
* lang/python/tests/t-verify.py (check_result): Here, the difference
between 2 and 3 really matters.  We cannot change the char *
conversion in Python 2 without breaking all existing applications, and
using bytestrings in Python 3 would be very inconvenient.

Signed-off-by: Justus Winter <[email protected]>

1 files changed, 22 insertions, 14 deletions

diff --git a/lang/python/helpers.c b/lang/python/helpers.c
index 5b13fee0..bc8aed40 100644
--- a/lang/python/helpers.c
+++ b/lang/python/helpers.c
@@ -833,17 +833,21 @@ static ssize_t pyDataWriteCb(void *hook, const void *buffer, size_t size)
     goto leave;
   }
 
-  if (! PyLong_Check(retval)) {
+#if PY_MAJOR_VERSION < 3
+  if (PyInt_Check(retval))
+    result = PyInt_AsSsize_t(retval);
+  else
+#endif
+  if (PyLong_Check(retval))
+    result = PyLong_AsSsize_t(retval);
+  else {
     PyErr_Format(PyExc_TypeError,
-                 "expected int from read callback, got %s",
+                 "expected int from write callback, got %s",
                  retval->ob_type->tp_name);
     _pyme_stash_callback_exception(self);
     result = -1;
-    goto leave;
   }
 
-  result = PyLong_AsSsize_t(retval);
-
  leave:
   Py_XDECREF(retval);
   return result;
@@ -894,21 +898,25 @@ static off_t pyDataSeekCb(void *hook, off_t offset, int whence)
     goto leave;
   }
 
-  if (! PyLong_Check(retval)) {
+#if PY_MAJOR_VERSION < 3
+  if (PyInt_Check(retval))
+    result = PyInt_AsLong(retval);
+  else
+#endif
+  if (PyLong_Check(retval))
+#if defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64
+    result = PyLong_AsLongLong(retval);
+#else
+    result = PyLong_AsLong(retval);
+#endif
+  else {
     PyErr_Format(PyExc_TypeError,
-                 "expected int from read callback, got %s",
+                 "expected int from seek callback, got %s",
                  retval->ob_type->tp_name);
     _pyme_stash_callback_exception(self);
     result = -1;
-    goto leave;
   }
 
-#if defined(_FILE_OFFSET_BITS) && _FILE_OFFSET_BITS == 64
-  result = PyLong_AsLongLong(retval);
-#else
-  result = PyLong_AsLong(retval);
-#endif
-
  leave:
   Py_XDECREF(retval);
   return result;