Fix iteration over list of tuples.

CHANGES.rst

@@ -22,6 +22,7 @@ Changelog
 
     - Raise proper error if prefix is not simple.
     - Fix complex multisort in Python 3.
+    - Fix iteration over list of tuples in Python 3.
 
 
 3.0b4 (2018-07-12)

src/DocumentTemplate/DT_In.py

@@ -341,6 +341,7 @@
 from DocumentTemplate.DT_Util import ValidationError, Eval
 from DocumentTemplate.DT_Util import simple_name, add_with_prefix
 from DocumentTemplate.DT_InSV import sequence_variables, opt
+from zope.sequencesort.ssort import _Smallest
 
 if sys.version_info > (3, 0):
     unicode = str
@@ -831,6 +832,7 @@ def sort_sequence(self, sequence, md):
                         try:
                             k = k()
                         except Exception:
+                            k = _Smallest
                             pass
 
             s.append((k, client))

src/DocumentTemplate/tests/test_DT_In.py

@@ -10,9 +10,14 @@ class DummySection(object):
 class Dummy(object):
     """Dummy with attribute"""
 
-    def __init__(self, name, number=0):
+    def __init__(self, name, number=0, _callable=0):
         self.name = name
         self.number = number
+        self._callable = _callable
+
+    @property
+    def maybe_callable(self):
+        return self._callable
 
 
 class TestIn(unittest.TestCase):
@@ -306,6 +311,53 @@ def test_DT_In__InClass__renderwob__07(self):
             'Item 4: alberta , 2')
         self.assertEqual(res, expected)
 
+    def test_DT_In__InClass__renderwob__08(self):
+        """It can iterate over list of tuples."""
+        seq = [('alberta', 3), ('ylberta', 1), ('barnie', 2)]
+        html = self.doc_class(
+            '<dtml-in seq>'
+            'Item <dtml-var sequence-number>: '
+            '<dtml-var sequence-item>'
+            '</dtml-in>')
+        res = html(seq=seq)
+        expected = (
+            'Item 1: 3'
+            'Item 2: 1'
+            'Item 3: 2')
+        self.assertEqual(res, expected)
+        # also sorted
+        html = self.doc_class(
+            '<dtml-in seq sort>'
+            'Item <dtml-var sequence-number>: '
+            '<dtml-var sequence-item>'
+            '</dtml-in>')
+        res = html(seq=seq)
+        expected = (
+            'Item 1: 3'
+            'Item 2: 2'
+            'Item 3: 1')
+        self.assertEqual(res, expected)
+
+    def test_DT_In__InClass__renderwob__09(self):
+        """It can also contain callables as values."""
+        # It catches errors and treats those as smallest
+        seq = [
+            Dummy('alberta', _callable=lambda: 3),
+            Dummy('ylberta', _callable=lambda: 0),
+            Dummy('barnie', _callable=lambda: [][2]),
+        ]
+        html = self.doc_class(
+            '<dtml-in seq sort=maybe_callable/cmp>'
+            'Item <dtml-var sequence-number>: '
+            '<dtml-var sequence-var-name>'
+            '</dtml-in>')
+        res = html(seq=seq)
+        expected = (
+            'Item 1: barnie'
+            'Item 2: ylberta'
+            'Item 3: alberta')
+        self.assertEqual(res, expected)
+
     def test_DT_In__InClass__renderwb__01(self):
         """It does not allow strings as sequence in batch mode."""
         html = self.doc_class(

tox.ini

@@ -30,7 +30,7 @@ commands =
     coverage combine
     coverage html
     coverage xml
-    coverage report --fail-under=68
+    coverage report --fail-under=70
 
 [testenv:flake8]
 basepython = python3.6