def test_iter_defaults():
"""It doesn't yield keys from defaults."""
this = ODD(a=1)
that = ODD(b=2)
this.defaults = dict(c=3)
that.defaults = dict(d=4)
a = DictTree(this, that)
assert list(sorted(a)) == ['a', 'b']
def test_get():
"""It returns values correctly via the `get` interface."""
a = DictTree({'a': 1}, {'b': 2})
# key exists in this
assert a.get('a') == 1
assert a.get('a', 42) == 1
# key exists in that
assert a.get('b') == 2
assert a.get('b', 42) == 2
# key does not exist
assert a.get('e') is None
assert a.get('e', 42) == 42
def test_nesting():
"""It slices without duplicating data."""
this_a = dict(b=1)
this = dict(a=this_a)
that_a = dict(b=2)
that = dict(a=that_a)
both = DictTree(this, that)
sub = both['a']
assert sub._tree == (this_a, that_a)
r_this_a, r_that_a = sub._tree
assert id(r_this_a) == id(this_a)
assert id(r_that_a) == id(that_a)
def test_defaults_getitem_nested():
"""It preserves the defaults_ behaviour of ODD in nested dicts."""
this = ODD()
that = ODD(a=2)
both = DictTree(dict(a=this), dict(a=that))
# default in this gets overridden by value in that
this.defaults_ = dict(a=1)
that.defaults_ = dict()
assert both['a']['a'] == 2
# default in first dict gets priority
this.defaults_ = dict(b=1)
that.defaults_ = dict(b=2)
assert both['a']['b'] == 1
def test_defaults_getitem_dict():
"""It returns defaults if a value isn't set."""
this = ODD()
that = ODD(a=2)
both = DictTree(this, that)
# default in this gets overridden by value in that
this.defaults_ = dict(a=1)
that.defaults_ = dict()
assert both['a'] == 2
# default in first dict gets priority
this.defaults_ = dict(b=1)
that.defaults_ = dict(b=2)
assert both['b'] == 1
def test_odd_getitem():
"""It returns default values if none of the dicts contains the key."""
this = ODD(a=1)
this.defaults_ = dict(c=3)
that = ODD(b=2)
that.defaults_ = dict(d=4)
both = DictTree(this, that)
# key from this
assert both['a'] == 1
# key from that
assert both['b'] == 2
# default from this
assert both['c'] == 3
# default from that
assert both['d'] == 4
# missing value
with pytest.raises(KeyError):
both['e']
def test_getitem():
"""It returns values prioritised correctly via the `getitem` interface."""
this = {
'a': 1,
'b': 2,
'f': {
'x': 5,
'y': 6
}
}
that = {
'b': 3,
'd': 4,
'f': {
'y': 7,
'z': 8
}
}
a = DictTree(this, that)
# key from this
assert a['a'] == 1
# key from that
assert a['d'] == 4
# key from this overrides key from that
assert a['b'] == 2
# dict from both
f = a['f']
assert f._tree == (this['f'], that['f'])
assert f['x'] == 5 # key from this
assert f['y'] == 6 # key from this which is also in that
assert f['z'] == 8 # key from that
# mutate definition object
this['f']['y'] = 42
assert a['f']['y'] == 42
def test_iter():
"""It yields keys from all dictionaries."""
a = DictTree({'a': 1}, {'a': 2, 'b': 3})
assert list(sorted(a)) == ['a', 'b']
def test_eq():
"""It compares to identical instances."""
assert DictTree({'a': 1}) == DictTree({'a': 1})
assert DictTree({'a': 1}) != DictTree({'a': 2})
assert DictTree({'a': 1}) != {'a': 1}
def test_get_dict():
"""It slices correctly via the `get` interface."""
a = DictTree({'a': {'b': 1}}, {'a': {'b': 2}})
assert a.get('a') == DictTree({'b': 1}, {'b': 2})