Rework bot and test parsing to allow receipt of (bot, set(test)) specifications.

presubmit_support.py

Index: presubmit_support.py
diff --git a/presubmit_support.py b/presubmit_support.py
index 8f3575cefca5f2f17706a9cb790141ba35f28b8d..52fae3a611aa8d223a76fefba764bc8ff062fca1 100755
--- a/presubmit_support.py
+++ b/presubmit_support.py
@@ -1032,13 +1032,21 @@ class GetTrySlavesExecuter(object):
             (type(result), str(result)))
       for item in result:
         if not isinstance(item, basestring):
-          raise PresubmitFailure('All try slaves names must be strings.')
-        if item != item.strip():
+          if not isinstance(item, tuple):
+            raise PresubmitFailure('PRESUBMIT.py returned invalid tryslave/test'
+                                   ' format.')
+          # New-style [('bot', set(['tests']))] format.
+          botname = item[0]
+        else:
+          # Old-style ['bot'] format.
+          botname = item
+
+        if botname != botname.strip():
           raise PresubmitFailure(
               'Try slave names cannot start/end with whitespace')
-        if ',' in item:
+        if ',' in botname:
           raise PresubmitFailure(
-              'Do not use \',\' separated builder or test names: %s' % item)
+              'Do not use \',\' separated builder or test names: %s' % botname)
     else:
       result = []
     return result
@@ -1084,7 +1092,16 @@ def DoGetTrySlaves(change,
     results += executer.ExecPresubmitScript(
         presubmit_script, filename, project, change)
 
-  slaves = list(set(results))
+  if results and isinstance(results[0], tuple):
+    # New-style [('bot', set(['tests']))] format.
+    slave_dict = {}
+    for result in results:
+      slave_dict.setdefault(result[0], set()).update(result[1])
+    slaves = list(slave_dict.iteritems())
+  else:
+    # Old-style ['bot'] format.
+    slaves = list(set(results))

[ghost stip (do not use), 2013/11/01 02:13:00]

looks like it would just update slaves after each run, so the indent worked even
though it should have been one less

+
   if slaves and verbose:
     output_stream.write(', '.join(slaves))
     output_stream.write('\n')