Make recipes.py run give better messages.

recipe_engine/run.py

Index: recipe_engine/run.py
diff --git a/recipe_engine/run.py b/recipe_engine/run.py
index 2d1b3f3ebfb297c19f9b96b530c5a41123a1df9c..9c94f4d835ee4ac14691607141c8faab5a3997bb 100644
--- a/recipe_engine/run.py
+++ b/recipe_engine/run.py
@@ -1,4 +1,4 @@
-# Copyright (c) 2013-2015 The Chromium Authors. All rights reserved.
+# Copyright (c) 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.
 
@@ -64,6 +64,7 @@ iterable_of_things.
 """
 
 import collections
+import json
 import os
 import sys
 import traceback
@@ -179,7 +180,7 @@ ENV_WHITELIST_POSIX = BUILDBOT_MAGIC_ENV | set([
 RecipeResult = collections.namedtuple('RecipeResult', 'result')
 
 
-def run_steps(properties, stream_engine, step_runner, universe):
+def run_steps(properties, stream_engine, step_runner, universe_view):
   """Runs a recipe (given by the 'recipe' property).
 
   Args:
@@ -187,7 +188,7 @@ def run_steps(properties, stream_engine, step_runner, universe):
       'recipe' property defines which recipe to actually run.
     stream_engine: the StreamEngine to use to create individual step streams.
     step_runner: The StepRunner to use to 'actually run' the steps.
-    universe: The RecipeUniverse to use to load the recipes & modules.
+    universe_view: The RecipeUniverse to use to load the recipes & modules.
 
   Returns: RecipeResult
   """
@@ -205,7 +206,7 @@ def run_steps(properties, stream_engine, step_runner, universe):
     'TESTING_SLAVENAME' in os.environ)):
     properties['use_mirror'] = False
 
-  engine = RecipeEngine(step_runner, properties, universe)
+  engine = RecipeEngine(step_runner, properties, universe_view)
 
   # Create all API modules and top level RunSteps function.  It doesn't launch
   # any recipe code yet; RunSteps needs to be called.
@@ -218,11 +219,14 @@ def run_steps(properties, stream_engine, step_runner, universe):
     if 'use_mirror' in properties:
       del properties_to_print['use_mirror']
 
+    root_package = universe_view.universe.package_deps.root_package
     run_recipe_help_lines = [
-        'To repro this locally, run the following line from a build checkout:',
+        'To repro this locally, run the following line from a %s checkout:' % (
+            root_package.name),
         '',
-        './scripts/tools/run_recipe.py %s --properties-file - <<EOF' % recipe,
-        repr(properties_to_print),
+        '%s run %s --properties-file - <<EOF' % (os.path.join(
+            '.', root_package.relative_recipes_dir, 'recipes.py'), recipe),

[iannucci, 2016/04/14 01:18:28]

I think there's a discrepancy between run_recipe and recipes.py; particularly,
run_recipe sets the CWD. Unless you fixed this some other way?

+        '%s' % json.dumps(properties_to_print),
         'EOF',
         '',
         'To run on Windows, you can put the JSON in a file and redirect the',
@@ -237,7 +241,7 @@ def run_steps(properties, stream_engine, step_runner, universe):
 
     # Find and load the recipe to run.
     try:
-      recipe_script = universe.load_recipe(recipe)
+      recipe_script = universe_view.load_recipe(recipe)
       s.write_line('Running recipe with %s' % (properties,))
 
       api = loader.create_recipe_api(recipe_script.LOADED_DEPS,