# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.
import copy
def merge_to(source, dest):
"""
Merge dict
and arrays (override scalar values)
Keys
from source override keys
from dest,
and elements
from lists
in source
are appended to lists
in dest.
:param dict source: to copy
from
:param dict dest: to copy to (modified
in place)
"""
for key, value
in source.items():
# Override mismatching or empty types
if type(value) != type(dest.get(key)):
# noqa
dest[key] = source[key]
continue
# Merge dict
if isinstance(value, dict):
merge_to(value, dest[key])
continue
if isinstance(value, list):
dest[key] = dest[key] + source[key]
continue
dest[key] = source[key]
return dest
def merge(*objects):
"""
Merge the given objects, using the semantics described
for merge_to,
with
objects later
in the list taking precedence.
From an inheritance
perspective,
"parents" should be listed before
"children".
Returns the result without modifying any arguments.
"""
if len(objects) == 1:
return copy.deepcopy(objects[0])
return merge_to(objects[-1], merge(*objects[:-1]))
