Make runner task sorting pay special attention to integers which come be...

runner/lib/graph.py

@@ -40,6 +40,26 @@ def _missing_tasks(self):
         lst = [node._missing_dependencies() for node in self._nodes.values()]
         return set(itertools.chain.from_iterable(lst))
 
+    @staticmethod
+    def task_comparator(x, y):
+        """
+        A comparator which takes into account the common task name format:
+            <int:prefix>-<str:taskname>
+        """
+        if '-' in x and '-' in y:
+            x_pre = x.split('-')[0]
+            y_pre = y.split('-')[0]
+            if x_pre.isdigit() and y_pre.isdigit() and (x_pre != y_pre):
+                x = int(x_pre)
+                y = int(y_pre)
+                # double zeros are a special case: when compared to a single
+                # zero, it should be considered as "less." To make this work
+                # for any number of zeros, we'll convert them into negatives.
+                if (x == 0 and y == 0) and (len(x_pre) > 1 or len(y_pre) > 1):
+                    x = len(x_pre) * -1
+                    y = len(y_pre) * -1
+        return cmp(x, y)
+
     def sequential_ordering(self):
         """Topological sort, ignores parallelisation possibilities
         Algorithm is Kahn (1962),
@@ -50,7 +70,11 @@ def sequential_ordering(self):
         graph = copy.deepcopy(self._nodes.values())
         # our starting nodes should be sorted for users who expect init
         # [runlevel] type behavior
-        no_inc_edges = sorted(self._start_nodes(graph), key=lambda x: x.name)
+        no_inc_edges = sorted(
+            self._start_nodes(graph),
+            key=lambda x: x.name,
+            cmp=TaskGraph.task_comparator
+        )
         while no_inc_edges:
             n = no_inc_edges.pop()
             to_ret.append(n.name)

tests/test-graph.py

@@ -12,6 +12,23 @@
 )
 
 
+def test_graph_comparator():
+    """
+    We use a custom comparator to ensure that tasks sort the way we want
+    by name (if no config is specified)
+    """
+    assert TaskGraph.task_comparator('99-abc', '100-abc') == -1
+    assert TaskGraph.task_comparator('100-abc', '99-abc') == 1
+    assert TaskGraph.task_comparator('99-abc', '99-abc') == 0
+    assert TaskGraph.task_comparator('0-bob', '00-jim') == 1
+    assert TaskGraph.task_comparator('abcd', '0-abcd') == 1
+    assert TaskGraph.task_comparator('abc', 'abc') == 0
+    assert TaskGraph.task_comparator('abc', 'def') == -1
+    assert TaskGraph.task_comparator('1', '2') == -1
+    assert TaskGraph.task_comparator('1', '1') == 0
+    assert TaskGraph.task_comparator('2', '1') == 1
+
+
 def test_graph_ok_no_deps():
     ok = [('a', []), ('z', []), ('y', []), ('0', []), ('9', [])]
     graph = TaskGraph(map(TaskConfig.fromtuple, ok))