Make recipes.py run give better messages.

unittests/errors_test.py

 #!/usr/bin/env python
 # Copyright 2014 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.
 
 import os
 import shutil
 import subprocess
 import tempfile
 import unittest
 
 import repo_test_util
 from repo_test_util import ROOT_DIR
 
 
 class RecipeRepo(object):
-  def __init__(self):
+  def __init__(self, recipes_path=''):
     self._root = tempfile.mkdtemp()
     os.makedirs(os.path.join(self._root, 'infra', 'config'))
     self._recipes_cfg = os.path.join(
         self._root, 'infra', 'config', 'recipes.cfg')
     with open(self._recipes_cfg, 'w') as fh:
       fh.write("""
 api_version: 1
 project_id: "testproj"
+recipes_path: "%s"
 deps {
   project_id: "recipe_engine"
   url: "%s"
   branch: "master"
   revision: "HEAD"
 }
-""" % ROOT_DIR)
+""" % (recipes_path, ROOT_DIR))
     self._recipes_dir = os.path.join(self._root, 'recipes')
     os.mkdir(self._recipes_dir)
     self._modules_dir = os.path.join(self._root, 'recipe_modules')
     os.mkdir(self._modules_dir)
 
   def make_recipe(self, recipe, contents):
     with open(os.path.join(self._recipes_dir, '%s.py' % recipe), 'w') as fh:
       fh.write(contents)
 
   def make_module(self, name, init_contents, api_contents):
@@ skipping 137 matching lines @@
   pass
 
 def GenTests(api):
   yield api.test('basic') + api.expect_exception('AssertionError')
 """)
       self._test_cmd(repo, ['simulation_test', 'train', 'unconsumed_assertion'],
         asserts=lambda stdout, stderr: self.assertRegexpMatches(
             stdout + stderr, 'Unconsumed'),
         retcode=1)
 
+  def test_run_recipe_help(self):
+    with RecipeRepo(recipes_path='foo/bar') as repo:
+      repo.make_recipe('do_nothing', """
+DEPS = []
+def RunSteps(api):
+ pass
+""")
+      subp = subprocess.Popen(
+                    repo.recipes_cmd + ['run', 'do_nothing'],
+                              stdout=subprocess.PIPE)
+      stdout, _ = subp.communicate()
+      self.assertRegexpMatches(
+          stdout, r'from the root of a \'testproj\' checkout')
+      self.assertRegexpMatches(
+          stdout, r'\./foo/bar/recipes\.py --package=.* run .* do_nothing')
+
+
+
+
+
 if __name__ == '__main__':
   unittest.main()