Get rid of the Command class completely.

GoalRunner now just extends object.

The functionality previously in Command is now in GoalRunner.

Most of the functionality in pants_exe.py is now in GoalRunner too.

RIP old pants...

Testing Done:
All integration and unit tests pass.

Reviewed at https://rbcommons.com/s/twitter/r/1465/

src/python/pants/backend/core/BUILD

@@ -9,7 +9,6 @@ python_library(
     'src/python/pants/backend/core/targets:all',
     'src/python/pants/backend/core/tasks:all',
     'src/python/pants/base:build_file_aliases',
-    'src/python/pants/commands:goal_runner',
     'src/python/pants/goal:task_registrar',
     ':core',
   ]

src/python/pants/backend/core/register.py

@@ -37,7 +37,6 @@
 from pants.base.build_environment import get_buildroot, pants_version
 from pants.base.build_file_aliases import BuildFileAliases
 from pants.base.source_root import SourceRoot
-from pants.commands.goal_runner import GoalRunner
 from pants.goal.task_registrar import TaskRegistrar as task
 
 
@@ -92,10 +91,6 @@ def build_file_aliases():
   )
 
 
-def register_commands():
-  GoalRunner._register()
-
-
 def register_goals():
   # Getting help.
   task(name='goals', action=ListGoals

src/python/pants/base/extension_loader.py

@@ -118,7 +118,6 @@ def load_backend(build_configuration, backend_package):
                         {},  # globals
                         {},  # locals
                         ['build_file_aliases',
-                         'register_commands',
                          'register_goals'])
   except ImportError as e:
     raise BackendConfigurationError('Failed to load the {backend} backend: {error}'
@@ -137,5 +136,4 @@ def invoke_entrypoint(name):
   if build_file_aliases:
     build_configuration.register_aliases(build_file_aliases)
 
-  invoke_entrypoint('register_commands')
   invoke_entrypoint('register_goals')

src/python/pants/bin/BUILD

@@ -5,8 +5,7 @@ python_library(
   name = 'pants_exe',
   sources = ['pants_exe.py'],
   dependencies = [
-    '3rdparty/python:psutil',
-    '3rdparty/python/twitter/commons:twitter.common.dirutil',
+
     'src/python/internal_backend/repositories:plugin',
     'src/python/pants/backend/android:plugin',
     'src/python/pants/backend/authentication:authentication',
@@ -17,12 +16,6 @@ python_library(
     'src/python/pants/backend/python:plugin',
     'src/python/pants/base:address',
     'src/python/pants/base:build_environment',
-    'src/python/pants/base:build_file_address_mapper',
-    'src/python/pants/base:build_file_parser',
-    'src/python/pants/base:build_graph',
-    'src/python/pants/base:config',
-    'src/python/pants/base:extension_loader',
-    'src/python/pants/commands:command',
 
     # XXX these are necessary to parse BUILD.commons.  Should instead be
     # added as plugins to pants.ini
@@ -33,22 +26,14 @@ python_library(
     'src/python/pants/backend/jvm/tasks:checkstyle',
     'src/python/pants/backend/python:python_chroot',
     'src/python/pants/scm:git',
-
-    # XXX The remaining are clear abstraction leaks.
-    # The goal target should be goal:run_tracker but it is inseparable from goal; also
-    # an abstraction leak.
-    'src/python/pants/backend/jvm/tasks:nailgun_task',
-    'src/python/pants/goal:initialize_reporting',
-    'src/python/pants/goal:run_tracker',
-    'src/python/pants/reporting',
   ],
 )
 
 target(
   name='pants_binary_deps',
   dependencies=[
     ':pants_exe',
-    'src/python/pants/commands:pants_new',
+    'src/python/pants/commands:goal_runner',
   ]
 )
 

src/python/pants/bin/pants_exe.py

@@ -6,23 +6,12 @@
                         print_function, unicode_literals)
 
 import logging
-import optparse
 import os
 import sys
 import traceback
 
-from pants.backend.jvm.tasks.nailgun_task import NailgunTask
 from pants.base.build_environment import get_buildroot, pants_version
-from pants.base.build_file_address_mapper import BuildFileAddressMapper
-from pants.base.build_file_parser import BuildFileParser
-from pants.base.build_graph import BuildGraph
-from pants.base.config import Config
-from pants.base.extension_loader import load_plugins_and_backends
-from pants.base.workunit import WorkUnit
-from pants.commands.command import Command
-from pants.goal.initialize_reporting import initial_reporting
-from pants.goal.run_tracker import RunTracker
-from pants.reporting.report import Report
+from pants.commands.goal_runner import GoalRunner
 
 
 _LOG_EXIT_OPTION = '--log-exit'
@@ -54,40 +43,10 @@ def _unhandled_exception_hook(exception_class, exception, tb):
   _exit_and_fail(msg)
 
 
-def _find_all_commands():
-  for cmd in Command.all_commands():
-    cls = Command.get_command(cmd)
-    yield '%s\t%s' % (cmd, cls.__doc__)
-
-
-def _synthesize_command(root_dir, args):
-  command = args[0]
-
-  if command in Command.all_commands():
-    subcommand_args = args[1:] if len(args) > 1 else []
-    return command, subcommand_args
-
-  if command.startswith('-'):
-    _exit_and_fail('Invalid command: %s' % command)
-
-  _exit_and_fail('Pants build missing a command: args={args} tb=\n{tb}'
-                 .format(args=args, tb=traceback.format_exc()))
-
-
-def _parse_command(root_dir, args):
-  command, args = _synthesize_command(root_dir, args)
-  return Command.get_command(command), args
-
 def _run():
   # Place the registration of the unhandled exception hook as early as possible in the code.
   sys.excepthook = _unhandled_exception_hook
 
-  """
-  To add additional paths to sys.path, add a block to the config similar to the following:
-  [main]
-  roots: ['src/python/pants_internal/test/',]
-  """
-
   logging.basicConfig()
   version = pants_version()
   if len(sys.argv) == 2 and sys.argv[1] == _VERSION_OPTION:
@@ -97,85 +56,10 @@ def _run():
   if not os.path.exists(root_dir):
     _exit_and_fail('PANTS_BUILD_ROOT does not point to a valid path: %s' % root_dir)
 
-  if len(sys.argv) < 2:
-    argv = ['goal']
-  else:
-    argv = sys.argv[1:]
-  # Hack to force ./pants -h etc. to redirect to goal.
-  if argv[0] != 'goal' and set(['-h', '--help', 'help']).intersection(argv):
-    argv = ['goal'] + argv
-
-  parser = optparse.OptionParser(add_help_option=False, version=version)
-  parser.add_option(_LOG_EXIT_OPTION,
-                    action='store_true',
-                    default=False,
-                    dest='log_exit',
-                    help='Log an exit message on success or failure.')
-
-  # Temporary hack, so that backend-loading code can access config via the cache.
-  # Later, in GoalRunner, we bootstrap the config properly and cache it, overwriting this one.
-  # We need this hacked-in support for PANTS_CONFIG_OVERRIDE because ci.sh uses it in the
-  # self-distribution tests. In normal code PANTS_CONFIG_OVERRIDE is supported via the
-  # --config-override option.
-  # This will go away completely once Command is gone.
-  override = os.environ.get('PANTS_CONFIG_OVERRIDE', None)
-  configpaths = [os.path.join(get_buildroot(), 'pants.ini')]
-  if override:
-    configpaths.append(override)
-  config = Config.load(configpaths)
-  Config.cache(config)
-
-  # XXX(wickman) This should be in the command goal, not in pants_exe.py!
-  run_tracker = RunTracker.from_config(config)
-  report = initial_reporting(config, run_tracker)
-  run_tracker.start(report)
-
-  url = run_tracker.run_info.get_info('report_url')
-  if url:
-    run_tracker.log(Report.INFO, 'See a report at: %s' % url)
-  else:
-    run_tracker.log(Report.INFO, '(To run a reporting server: ./pants goal server)')
-
-  backend_packages = config.getlist('backends', 'packages', [])
-  plugins = config.getlist('backends', 'plugins', [])
-
-  build_configuration = load_plugins_and_backends(plugins, backend_packages)
-  build_file_parser = BuildFileParser(build_configuration=build_configuration,
-                                      root_dir=root_dir,
-                                      run_tracker=run_tracker)
-  address_mapper = BuildFileAddressMapper(build_file_parser)
-  build_graph = BuildGraph(run_tracker=run_tracker, address_mapper=address_mapper)
-
-  command_class, command_args = _parse_command(root_dir, argv)
-  command = command_class(run_tracker,
-                          root_dir,
-                          parser,
-                          command_args,
-                          build_file_parser,
-                          address_mapper,
-                          build_graph)
-  try:
-    try:
-      result = command.run()
-      if result:
-        run_tracker.set_root_outcome(WorkUnit.FAILURE)
-      _do_exit(result)
-    except KeyboardInterrupt:
-      command.cleanup()
-      raise
-    except Exception:
-      run_tracker.set_root_outcome(WorkUnit.FAILURE)
-      raise
-  finally:
-    run_tracker.end()
-    # Must kill nailguns only after run_tracker.end() is called, because there may still
-    # be pending background work that needs a nailgun.
-    # TODO(Eric Ayers) simplify after setup_py goes away.
-    if (hasattr(command.old_options, 'cleanup_nailguns') and command.old_options.cleanup_nailguns) \
-        or (hasattr(command, 'new_options')
-            and command.new_options.for_global_scope().kill_nailguns) \
-        or config.get('nailgun', 'autokill', default=False):
-      NailgunTask.killall(None)
+  goal_runner = GoalRunner(root_dir)
+  goal_runner.setup()
+  result = goal_runner.run()
+  _do_exit(result)
 
 def main():
   try:

src/python/pants/commands/BUILD

@@ -1,45 +1,31 @@
 # Copyright 2014 Pants project contributors (see CONTRIBUTORS.md).
 # Licensed under the Apache License, Version 2.0 (see LICENSE).
 
-python_library(
-  name = 'command',
-  sources = ['command.py'],
-  dependencies = [
-    '3rdparty/python/twitter/commons:twitter.common.collections',
-    'src/python/pants/base:build_file',
-    'src/python/pants/base:build_file_parser',
-    'src/python/pants/base:target',
-    'src/python/pants/base:build_graph',
-  ]
-)
-
-python_library(
-  name = 'pants_new',
-  dependencies = [
-    ':goal_runner',
-  ]
-)
 
 python_library(
   name = 'goal_runner',
   sources = ['goal_runner.py'],
   dependencies = [
-    ':command',
     '3rdparty/python/twitter/commons:twitter.common.lang',
     '3rdparty/python/twitter/commons:twitter.common.log',
     'src/python/pants/backend/core/tasks:common',
     'src/python/pants/backend/core/tasks:task',
     'src/python/pants/backend/jvm/tasks:nailgun_task',
     'src/python/pants/base:address',
+    'src/python/pants/base:build_environment',
+    'src/python/pants/base:build_file_address_mapper',
+    'src/python/pants/base:build_file_parser',
+    'src/python/pants/base:build_graph',
     'src/python/pants/base:config',
     'src/python/pants/base:cmd_line_spec_parser',
+    'src/python/pants/base:extension_loader',
     'src/python/pants/base:target',
     'src/python/pants/base:workunit',
     'src/python/pants/engine',
+    'src/python/pants/goal',
     'src/python/pants/goal:context',
-    'src/python/pants/goal:error',
     'src/python/pants/goal:initialize_reporting',
-    'src/python/pants/goal',
+    'src/python/pants/goal:run_tracker',
     'src/python/pants/option',
     'src/python/pants/reporting',
     'src/python/pants/util:dirutil',