1 files changed, 35 insertions, 0 deletions
diff --git a/testing/mozharness/mozharness/base/parallel.py b/testing/mozharness/mozharness/base/parallel.py
new file mode 100755
index 0000000000..678dadeede
--- /dev/null
+++ b/testing/mozharness/mozharness/base/parallel.py
@@ -0,0 +1,35 @@
+#!/usr/bin/env python
+# ***** BEGIN LICENSE BLOCK *****
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this file,
+# You can obtain one at http://mozilla.org/MPL/2.0/.
+# ***** END LICENSE BLOCK *****
+"""Generic ways to parallelize jobs.
+"""
+
+
+# ChunkingMixin {{{1
+class ChunkingMixin(object):
+    """Generic Chunking helper methods."""
+
+    def query_chunked_list(self, possible_list, this_chunk, total_chunks, sort=False):
+        """Split a list of items into a certain number of chunks and
+        return the subset of that will occur in this chunk.
+
+        Ported from build.l10n.getLocalesForChunk in build/tools.
+        """
+        if sort:
+            possible_list = sorted(possible_list)
+        else:
+            # Copy to prevent altering
+            possible_list = possible_list[:]
+        length = len(possible_list)
+        for c in range(1, total_chunks + 1):
+            n = length // total_chunks
+            # If the total number of items isn't evenly divisible by the
+            # number of chunks, we need to append one more onto some chunks
+            if c <= (length % total_chunks):
+                n += 1
+            if c == this_chunk:
+                return possible_list[0:n]
+            del possible_list[0:n]