Enable sharding of individual testsuites in tools/test.py...

tools/test.py

Index: tools/test.py
===================================================================
--- tools/test.py	(revision 6231)
+++ tools/test.py	(working copy)
@@ -1181,6 +1181,12 @@
   result.add_option("--crankshaft",
                     help="Run with the --crankshaft flag",
                     default=False, action="store_true")
+  result.add_option("--shard-count",
+                    help="Split testsuites into this number of shards",
+                    default=1, type="int")
+  result.add_option("--shard-run",
+                    help="Run this shard from the split up tests.",
+                    default=1, type="int")
   result.add_option("--noprof", help="Disable profiling support",
                     default=False)
   return result
@@ -1302,6 +1308,20 @@
   millis = round(d * 1000) % 1000
   return time.strftime("%M:%S.", time.gmtime(d)) + ("%03i" % millis)
 
+def ShardTests(tests, options):
+  if options.shard_count < 2:
+    return tests
+  if options.shard_run < 1 or options.shard_run > options.shard_count:
+    print "shard-run not a valid number, should be in [1:shard-count]"
+    print "defaulting back to running all tests"
+    return tests
+  count = 0;
+  shard = []
+  for test in tests:
+    if count % options.shard_count == options.shard_run - 1:
+      shard.append(test);
+    count += 1
+  return shard
 
 def Main():
   parser = BuildOptions()
@@ -1385,7 +1405,7 @@
         globally_unused_rules = set(unused_rules)
       else:
         globally_unused_rules = globally_unused_rules.intersection(unused_rules)
-      all_cases += cases
+      all_cases += ShardTests(cases, options)
       all_unused.append(unused_rules)
 
   if options.cat: