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