Scripts for unity/jumbo (default disabled) compilation

build/config/merge_for_jumbo.py

Index: build/config/merge_for_jumbo.py
diff --git a/build/config/merge_for_jumbo.py b/build/config/merge_for_jumbo.py
new file mode 100755
index 0000000000000000000000000000000000000000..f6eb87dce72d09070b96b9288c0f379ccb043e0f
--- /dev/null
+++ b/build/config/merge_for_jumbo.py
@@ -0,0 +1,62 @@
+#!/usr/bin/env python
+#
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+"""This script creates a "jumbo" file which merges all incoming files
+for compiling.
+
+"""
+
+from __future__ import print_function
+
+import argparse
+
+
+def main():
+  parser = argparse.ArgumentParser()
+  parser.add_argument("--outputs", nargs="+", required=True,
+                      help='List of output files to split input into')
+  parser.add_argument("--file-list", required=True)
+  parser.add_argument("--verbose", action="store_true")
+  args = parser.parse_args()
+
+  output_count = len(args.outputs)
+
+  lines = []
+  # If written with gn |write_file| each file is on its own line.
+  with open(args.file_list) as file_list_file:
+    lines = [line.strip() for line in file_list_file if line.strip()]
+  # If written with gn |response_file_contents| the files are space separated.
+  inputs = []
+  for line in lines:
+    inputs.extend(line.split())
+  input_count = len(inputs)
+
+  written_inputs = 0
+  for output_index, output_file in enumerate(args.outputs):
+    # TODO: Check if the file is right already and then do not update it.
+    with open(output_file, "w") as out:
+      out.write("/* This is a Jumbo file. Don't edit. */\n\n")
+      out.write("/* Generated with merge_for_jumbo.py. */\n\n")
+      input_limit = (output_index + 1) * input_count / output_count
+      while written_inputs < input_limit:
+        filename = inputs[written_inputs]
+        written_inputs += 1
+        # The source list includes headers which should not be
+        # compiled, and Objective C files which will be special cased
+        # later since they will not compile correctly if included in a
+        # C++ file. We will just skip them here for now.
+        if filename.endswith((".h", ".mm")):
+          continue
+
+        out.write("#include \"%s\"\n" % filename)
+
+  if args.verbose:
+      print("Generated %s (%d files) based on %s" % (str(args.outputs),
+                                                     written_inputs,
+                                                     args.file_list))
+
+if __name__ == "__main__":
+    main()