test: promote --train to its own subcommand

recipe_engine/autoroll.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.
 
 from __future__ import print_function
 
 import json
 import os
 import subprocess
 import sys
@@ skipping 113 matching lines @@
   """
   # Use _local_ recipes.py, so that it checks out the pinned recipe engine,
   # rather than running recipe engine which may be at a different revision
   # than the pinned one.
   args = [
     sys.executable,
     os.path.join(repo_root, package_spec.recipes_path, 'recipes.py'),
   ]
   if not allow_fetch:
     args.append('--no-fetch')
-  args.extend(['test', 'run'])
+  args.append('test')
   if additional_args:
     args.extend(additional_args)
   p = subprocess.Popen(args, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
   output, _ = p.communicate()
   rc = p.returncode
   return rc, output
 
 
 def process_candidates(candidates, context, config_file, package_spec):
   roll_details = []
@@ skipping 17 matching lines @@
   # the maximal one, e.g. to jump over some reverts, or include fixes
   # landed later for incompatible API changes.
   for i, candidate in enumerate(candidates):
     print('  processing candidate #%d... ' % (i + 1), end='')
 
     spec = candidate.get_rolled_spec()
     config_file.write(spec.dump())
     fetch(context.repo_root, package_spec)
     write_new_recipes_py(context, spec, repo_cfg_block)
 
-    rc, output = run_simulation_test(context.repo_root, package_spec)
+    rc, output = run_simulation_test(context.repo_root, package_spec, ['run'])
     roll_details[i]['recipes_simulation_test'] = {
       'output': output,
       'rc': rc,
     }
 
     if rc == 0:
       print('SUCCESS!')
       trivial = True
       picked_roll_details = roll_details[i]
       break
     else:
       print('FAILED')
 
   if not picked_roll_details:
     print('looking for a nontrivial roll...')
 
     # Process candidates smallest first. If the roll is going to change
     # expectations, it should be minimal to avoid pulling too many unrelated
     # changes.
     for i, candidate in reversed(list(enumerate(candidates))):
       print('  processing candidate #%d... ' % (i + 1), end='')
 
       spec = candidate.get_rolled_spec()
       config_file.write(spec.dump())
       fetch(context.repo_root, package_spec)
       write_new_recipes_py(context, spec, repo_cfg_block)
 
       rc, output = run_simulation_test(
-          context.repo_root, package_spec, ['--train'])
+          context.repo_root, package_spec, ['train'])
       roll_details[i]['recipes_simulation_test_train'] = {
         'output': output,
         'rc': rc,
       }
 
       if rc == 0:
         print('SUCCESS!')
         trivial = False
         picked_roll_details = roll_details[i]
         break
@@ skipping 49 matching lines @@
 
   results = {}
   try:
     results = test_rolls(
       config_file, context, package_spec, args.projects or [])
   finally:
     if not results.get('success'):
       # Restore initial state. Since we could be running simulation tests
       # on other revisions, re-run them now as well.
       config_file.write(package_spec.dump())
-      run_simulation_test(context.repo_root, package_spec, ['--train'],
+      run_simulation_test(context.repo_root, package_spec, ['train'],
                           allow_fetch=True)
 
   if args.output_json:
     with open(args.output_json, 'w') as f:
       json.dump(
           results, f, default=default_json_encode, sort_keys=True, indent=4)
 
   return 0