Bug 913241 - Support chunking mochitests from mach; r=jmaher

testing/mochitest/mach_commands.py

@@ -98,7 +98,8 @@ class MochitestRunner(MozbuildObject):
 
     def run_desktop_test(self, suite=None, test_file=None, debugger=None,
         debugger_args=None, shuffle=False, keep_open=False, rerun_failures=False,
-        no_autorun=False, repeat=0, run_until_failure=False, slow=False):
+        no_autorun=False, repeat=0, run_until_failure=False, slow=False,
+        chunk_by_dir=0, total_chunks=None, this_chunk=None):
         """Runs a mochitest.
 
         test_file is a path to a test file. It can be a relative path from the
@@ -204,6 +205,9 @@ class MochitestRunner(MozbuildObject):
         options.testingModulesDir = os.path.join(self.tests_dir, 'modules')
         options.extraProfileFiles.append(os.path.join(self.distdir, 'plugins'))
         options.symbolsPath = os.path.join(self.distdir, 'crashreporter-symbols')
+        options.chunkByDir = chunk_by_dir
+        options.totalChunks = total_chunks
+        options.thisChunk = this_chunk
 
         options.failureFile = failure_file_path
 
@@ -315,6 +319,18 @@ def MochitestCommand(func):
         help='Delay execution between tests.')
     func = slow(func)
 
+    chunk_dir = CommandArgument('--chunk-by-dir', type=int,
+        help='Group tests together in chunks by this many top directories.')
+    func = chunk_dir(func)
+
+    chunk_total = CommandArgument('--total-chunks', type=int,
+        help='Total number of chunks to split tests into.')
+    func = chunk_total(func)
+
+    this_chunk = CommandArgument('--this-chunk', type=int,
+        help='If running tests by chunks, the number of the chunk to run.')
+    func = this_chunk(func)
+
     path = CommandArgument('test_file', default=None, nargs='?',
         metavar='TEST',
         help='Test to run. Can be specified as a single file, a ' \