[Android] Adds python option for EMMA coverage

build/android/pylib/utils/command_option_parser.py

+# Copyright 2013 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.
+
+"""An option parser which handles the first arg as a command.
+
+Add other nice functionality such as printing a list of commands
+and an example in usage.
+"""
+
+import optparse
+import sys
+
+
+class CommandOptionParser(optparse.OptionParser):
+  """Wrapper class for OptionParser to help with listing commands."""
+
+  def __init__(self, *args, **kwargs):
+    """Creates a CommandOptionParser.
+
+    Args:
+      commands_dict: A dictionary mapping command strings to an object defining
+          - add_options_func: Adds options to the option parser
+          - run_command_func: Runs the command itself.
+      example: An example command.
+      everything else: Passed to optparse.OptionParser contructor.
+    """
+    self.commands_dict = kwargs.pop('commands_dict', [])
+    self.example = kwargs.pop('example', '')
+    if not 'usage' in kwargs:
+      kwargs['usage'] = 'Usage: %prog <command> [options]'
+    optparse.OptionParser.__init__(self, *args, **kwargs)
+
+  #override
+  def get_usage(self):
+    normal_usage = optparse.OptionParser.get_usage(self)
+    command_list = self.get_command_list()
+    example = self.get_example()
+    return self.expand_prog_name(normal_usage + example + command_list)
+
+  #override
+  def get_command_list(self):
+    if self.commands_dict.keys():
+      return '\nCommands:\n  %s\n' % '\n  '.join(
+          sorted(self.commands_dict.keys()))
+    return ''
+
+  def get_example(self):
+    if self.example:
+      return '\nExample:\n  %s\n' % self.example
+    return ''
+
+
+def ParseAndExecute(option_parser, argv=None):
+  """Parses options/args from argv and runs the specified command.
+
+  Args:
+    option_parser: A CommandOptionParser object.
+    argv: Command line arguments. If None, automatically draw from sys.argv.
+
+  Returns:
+    An exit code.
+  """
+  if not argv:
+    argv = sys.argv
+
+    if len(argv) < 2 or argv[1] not in option_parser.commands_dict:
+      # Parse args first, if this is '--help', optparse will print help and exit
+      option_parser.parse_args(argv)
+      option_parser.error('Invalid command.')
+
+    command = argv[1]
+    option_parser.commands_dict[command].add_options_func(option_parser)
+    options, args = option_parser.parse_args(argv)
+    return option_parser.commands_dict[command].run_command_func(
+        command, options, args, option_parser)