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Diffstat (limited to 'deps/gyp/pylib/gyp/simple_copy.py')
-rw-r--r-- | deps/gyp/pylib/gyp/simple_copy.py | 46 |
1 files changed, 46 insertions, 0 deletions
diff --git a/deps/gyp/pylib/gyp/simple_copy.py b/deps/gyp/pylib/gyp/simple_copy.py new file mode 100644 index 0000000000..74c98c5a79 --- /dev/null +++ b/deps/gyp/pylib/gyp/simple_copy.py @@ -0,0 +1,46 @@ +# Copyright 2014 Google Inc. All rights reserved. +# Use of this source code is governed by a BSD-style license that can be +# found in the LICENSE file. + +"""A clone of the default copy.deepcopy that doesn't handle cyclic +structures or complex types except for dicts and lists. This is +because gyp copies so large structure that small copy overhead ends up +taking seconds in a project the size of Chromium.""" + +class Error(Exception): + pass + +__all__ = ["Error", "deepcopy"] + +def deepcopy(x): + """Deep copy operation on gyp objects such as strings, ints, dicts + and lists. More than twice as fast as copy.deepcopy but much less + generic.""" + + try: + return _deepcopy_dispatch[type(x)](x) + except KeyError: + raise Error('Unsupported type %s for deepcopy. Use copy.deepcopy ' + + 'or expand simple_copy support.' % type(x)) + +_deepcopy_dispatch = d = {} + +def _deepcopy_atomic(x): + return x + +for x in (type(None), int, long, float, + bool, str, unicode, type): + d[x] = _deepcopy_atomic + +def _deepcopy_list(x): + return [deepcopy(a) for a in x] +d[list] = _deepcopy_list + +def _deepcopy_dict(x): + y = {} + for key, value in x.iteritems(): + y[deepcopy(key)] = deepcopy(value) + return y +d[dict] = _deepcopy_dict + +del d |