[autoroll] make autoroller propagate changes to recipes.py.

unittests/repo_test_util.py

 # Copyright 2016 The LUCI Authors. All rights reserved.
 # Use of this source code is governed under the Apache License, Version 2.0
 # that can be found in the LICENSE file.
 
 """Utilities for testing with real repos (e.g. git)."""
 
 
 import contextlib
 import os
 import shutil
@@ skipping 71 matching lines @@
     return package.PackageSpec.load_proto(package.ProtoFile(config_file))
 
   def create_repo(self, name, spec):
     """Creates a real git repo with simple recipes.cfg."""
     repo_dir = os.path.join(self._root_dir, name)
     os.mkdir(repo_dir)
     with in_directory(repo_dir):
       subprocess.check_output(['git', 'init'])
       subprocess.check_output(['git', 'remote', 'add', 'origin', repo_dir])
       with open('recipes.py', 'w') as f:
-        f.write('import subprocess, sys\n'
-                'sys.exit(subprocess.call(\n'
-                '    [sys.executable, %r, "--package", %r] + sys.argv[1:]))' % (
-                    self._recipe_tool,
-                    os.path.join(repo_dir, 'infra', 'config', 'recipes.cfg')))
+        f.write('\n'.join([
+          'import subprocess, sys, os',
+          '#### PER-REPO CONFIGURATION (editable) ####',
+          'REPO_ROOT = "."',
+          'RECIPES_CFG = os.path.join("infra", "config", "recipes.cfg")',
+          '#### END PER-REPO CONFIGURATION ####',
+          'if sys.argv[1] != "fetch":',
+          '  sys.exit(subprocess.call(',
+          '      [sys.executable, %r, "--package", %r] + sys.argv[1:]))' % (
+            self._recipe_tool,
+            os.path.join(repo_dir, 'infra', 'config', 'recipes.cfg')),
+        ]))
       subprocess.check_output(['git', 'add', 'recipes.py'])
     rev = self.update_recipes_cfg(name, spec)
     return {
         'name': name,
         'root': repo_dir,
         'revision': rev,
         'spec': spec,
     }
 
   def repo_setup(self, repo_deps):
@@ skipping 205 matching lines @@
       message = ' '.join(
         ['update %r recipe_module: ' % name] +
         ['%s(%s)' % t for t in methods.iteritems()]
       )
       return self.commit_in_repo(repo, message)
 
   def reset_repo(self, repo, revision):
     """Resets repo contents to given revision."""
     with in_directory(repo['root']):
       subprocess.check_output(['git', 'reset', '--hard', revision])