dart-sdk/tools/find_depot_tools.py

# Copyright (c) 2011 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.
"""Small utility function to find depot_tools and add it to the python path.
Will throw an ImportError exception if depot_tools can't be found since it
imports breakpad.
"""

from __future__ import print_function

import os
import sys

def IsRealDepotTools(path):
    return os.path.isfile(os.path.join(path, 'gclient.py'))


def add_depot_tools_to_path():
    """Search for depot_tools and add it to sys.path."""
    # First look if depot_tools is already in PYTHONPATH.
    for i in sys.path:
        if i.rstrip(os.sep).endswith('depot_tools') and IsRealDepotTools(i):
            return i
    # Then look if depot_tools is in PATH, common case.
    for i in os.environ['PATH'].split(os.pathsep):
        if IsRealDepotTools(i):
            sys.path.append(i.rstrip(os.sep))
            return i
    # Rare case, it's not even in PATH, look upward up to root.
    root_dir = os.path.dirname(os.path.abspath(__file__))
    previous_dir = os.path.abspath(__file__)
    while root_dir and root_dir != previous_dir:
        i = os.path.join(root_dir, 'depot_tools')
        if IsRealDepotTools(i):
            sys.path.append(i)
            return i
        previous_dir = root_dir
        root_dir = os.path.dirname(root_dir)
    print('Failed to find depot_tools', file=sys.stderr)
    return None


add_depot_tools_to_path()

# pylint: disable=W0611
import breakpad