[graph] sort dot node/edge attribute for predictabilities. Closes #202314

2 files changed, 11 insertions, 7 deletions

diff --git a/ChangeLog b/ChangeLog
index 48b6c8c..3fda9e9 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,16 +1,20 @@
 ChangeLog for logilab.common
 ============================
 
+--
+   * graph: ensure output is orderd on node and graph ids (#202314)
+
+
 2013-16-12  --  0.60.1
     * modutils:
 
-    * don't propagate IOError when package's __init__.py file doesn't
-       exist (#174606)
+      * don't propagate IOError when package's __init__.py file doesn't
+         exist (#174606)
 
-    * ensure file is closed, may cause pb depending on the interpreter, eg
+      * ensure file is closed, may cause pb depending on the interpreter, eg
        pypy) (#180876)
-
-    * fix support for `extend_path` based nested namespace packages ;
+  
+      * fix support for `extend_path` based nested namespace packages ;
        Report and patch by John Johnson (#177651)
 
     * fix some cases of failing python3 install on windows platform / cross
diff --git a/graph.py b/graph.py
index 94a71b6..d62e8c0 100644
--- a/graph.py
+++ b/graph.py
@@ -134,14 +134,14 @@ class DotBackend:
         """
         attrs = ['%s="%s"' % (prop, value) for prop, value in props.items()]
         n_from, n_to = normalize_node_id(name1), normalize_node_id(name2)
-        self.emit('%s -> %s [%s];' % (n_from, n_to, ", ".join(attrs)) )
+        self.emit('%s -> %s [%s];' % (n_from, n_to, ', '.join(sorted(attrs))) )
 
     def emit_node(self, name, **props):
         """emit a node with given properties.
         node properties: see http://www.graphviz.org/doc/info/attrs.html
         """
         attrs = ['%s="%s"' % (prop, value) for prop, value in props.items()]
-        self.emit('%s [%s];' % (normalize_node_id(name), ", ".join(attrs)))
+        self.emit('%s [%s];' % (normalize_node_id(name), ', '.join(sorted(attrs))))
 
 def normalize_node_id(nid):
     """Returns a suitable DOT node id for `nid`."""