Devtools: refactor shell configuration logic.

mojo/devtools/common/devtoolslib/shell_config.py

Index: mojo/devtools/common/devtoolslib/shell_config.py
diff --git a/mojo/devtools/common/devtoolslib/shell_config.py b/mojo/devtools/common/devtoolslib/shell_config.py
new file mode 100644
index 0000000000000000000000000000000000000000..acc9c61719b4b2d8cce6cba7eb612bb334d6b61a
--- /dev/null
+++ b/mojo/devtools/common/devtoolslib/shell_config.py
@@ -0,0 +1,121 @@
+# Copyright 2015 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.
+
+"""Configuration for the shell abstraction.
+
+This module declares ShellConfig and knows how to compute it from command-line
+arguments, applying any default paths inferred from the checkout, configuration
+file, etc.
+"""
+
+from devtoolslib import paths
+
+
+class ShellConfig(object):
+  """Configuration for the shell abstraction."""
+
+  def __init__(self):
+    self.android = None
+    self.shell_path = None
+    self.origin = None
+    self.map_url_list = None
+    self.map_origin_list = None
+    self.sky = None
+    self.verbose = None
+
+    # Android-only.
+    self.adb_path = None
+    self.target_device = None
+    self.logcat_tags = None
+
+    # Desktop-only.
+    self.use_osmesa = None
+
+
+def add_shell_arguments(parser):
+  """Adds argparse arguments allowing to configure shell abstraction using
+  configure_shell() below.
+  """
+  # Arguments configuring the shell run.
+  parser.add_argument('--android', help='Run on Android',
+                      action='store_true')
+  parser.add_argument('--shell-path', help='Path of the Mojo shell binary.')
+  parser.add_argument('--origin', help='Origin for mojo: URLs. This can be a '
+                      'web url or a local directory path.')
+  parser.add_argument('--map-url', action='append',
+                      help='Define a mapping for a url in the format '
+                      '<url>=<url-or-local-file-path>')
+  parser.add_argument('--map-origin', action='append',
+                      help='Define a mapping for a url origin in the format '
+                      '<origin>=<url-or-local-file-path>')
+  parser.add_argument('--sky', action='store_true',
+                      help='Maps mojo:sky_viewer as the content handler for '
+                           'dart apps.')
+  parser.add_argument('-v', '--verbose', action="store_true",
+                      help="Increase output verbosity")
+
+  android_group = parser.add_argument_group('Android-only',
+      'These arguments apply only when --android is passed.')
+  android_group.add_argument('--adb-path', help='Path of the adb binary.')
+  android_group.add_argument('--target-device', help='Device to run on.')
+  android_group.add_argument('--logcat-tags', help='Comma-separated list of '
+                             'additional logcat tags to display.')
+
+  desktop_group = parser.add_argument_group('Desktop-only',
+      'These arguments apply only when running on desktop.')
+  desktop_group.add_argument('--use-osmesa', action='store_true',
+                             help='Configure the native viewport service '
+                             'for off-screen rendering.')
+
+  # Arguments allowing to indicate the configuration we are targeting when
+  # running within a Chromium-like checkout. These will go away once we have
+  # devtools config files, see https://github.com/domokit/devtools/issues/28.
+  chromium_config_group = parser.add_argument_group('Chromium configuration',
+      'These arguments allow to infer paths to tools and build results '
+      'when running withing a Chromium-like checkout')
+  debug_group = chromium_config_group.add_mutually_exclusive_group()
+  debug_group.add_argument('--debug', help='Debug build (default)',
+                           default=True, action='store_true')
+  debug_group.add_argument('--release', help='Release build', default=False,
+                           dest='debug', action='store_false')
+  chromium_config_group.add_argument('--target-cpu',
+                                     help='CPU architecture to run for.',
+                                     choices=['x64', 'x86', 'arm'])
+
+
+def get_shell_config(script_args):
+  """Processes command-line options defined in add_shell_arguments(), applying
+  any inferred default paths and produces an instance of ShellConfig.
+
+  Returns:
+    An instance of ShellConfig.
+  """
+  # Infer paths based on the Chromium configuration options
+  # (--debug/--release, etc.), if running within a Chromium-like checkout.
+  inferred_paths = paths.infer_paths(script_args.android, script_args.debug,
+                                     script_args.target_cpu)
+
+  shell_config = ShellConfig()
+
+  shell_config.android = script_args.android
+  shell_config.shell_path = (script_args.shell_path or
+                             inferred_paths['shell_path'])
+  shell_config.origin = script_args.origin
+  shell_config.map_url_list = script_args.map_url
+  shell_config.map_origin_list = script_args.map_origin
+  shell_config.sky = script_args.sky
+  shell_config.verbose = script_args.verbose
+
+  # Android-only.
+  shell_config.adb_path = (script_args.adb_path or inferred_paths['adb_path'])
+  shell_config.target_device = script_args.target_device
+  shell_config.logcat_tags = script_args.logcat_tags
+
+  # Desktop-only.
+  shell_config.use_osmesa = script_args.use_osmesa
+
+  if (shell_config.android and not shell_config.origin and
+      inferred_paths['build_dir_path']):
+    shell_config.origin = inferred_paths['build_dir_path']
+  return shell_config