Files
RustPython/tests/snippets/dict.py

169 lines
3.4 KiB
Python

from testutils import assertRaises
assert dict(a=2, b=3) == {'a': 2, 'b': 3}
assert dict({'a': 2, 'b': 3}, b=4) == {'a': 2, 'b': 4}
assert dict([('a', 2), ('b', 3)]) == {'a': 2, 'b': 3}
assert {} == {}
assert not {'a': 2} == {}
assert not {} == {'a': 2}
assert not {'b': 2} == {'a': 2}
assert not {'a': 4} == {'a': 2}
assert {'a': 2} == {'a': 2}
nan = float('nan')
assert {'a': nan} == {'a': nan}
a = {'g': 5}
b = {'a': a, 'd': 9}
c = dict(b)
c['d'] = 3
c['a']['g'] = 2
assert a == {'g': 2}
assert b == {'a': a, 'd': 9}
a.clear()
assert len(a) == 0
a = {'a': 5, 'b': 6}
res = set()
for value in a.values():
res.add(value)
assert res == set([5,6])
count = 0
for (key, value) in a.items():
assert a[key] == value
count += 1
assert count == len(a)
res = set()
for key in a.keys():
res.add(key)
assert res == set(['a','b'])
# Deleted values are correctly skipped over:
x = {'a': 1, 'b': 2, 'c': 3, 'd': 3}
del x['c']
it = iter(x.items())
assert ('a', 1) == next(it)
assert ('b', 2) == next(it)
assert ('d', 3) == next(it)
with assertRaises(StopIteration):
next(it)
# Iterating a dictionary is just its keys:
assert ['a', 'b', 'd'] == list(x)
# Iterating view captures dictionary when iterated.
data = {1: 2, 3: 4}
items = data.items()
assert list(items) == [(1, 2), (3, 4)]
data[5] = 6
assert list(items) == [(1, 2), (3, 4), (5, 6)]
# Values can be changed during iteration.
data = {1: 2, 3: 4}
items = iter(data.items())
assert (1, 2) == next(items)
data[3] = "changed"
assert (3, "changed") == next(items)
# But we can't add or delete items during iteration.
d = {}
a = iter(d.items())
d['a'] = 2
b = iter(d.items())
assert ('a', 2) == next(b)
with assertRaises(RuntimeError):
next(a)
del d['a']
with assertRaises(RuntimeError):
next(b)
# View isn't itself an iterator.
with assertRaises(TypeError):
next(data.keys())
assert len(data.keys()) == 2
x = {}
x[1] = 1
assert x[1] == 1
x[7] = 7
x[2] = 2
x[(5, 6)] = 5
with assertRaises(KeyError):
x["not here"]
with assertRaises(TypeError):
x[[]] # Unhashable type.
x["here"] = "here"
assert x.get("not here", "default") == "default"
assert x.get("here", "default") == "here"
assert x.get("not here") == None
class LengthDict(dict):
def __getitem__(self, k):
return len(k)
x = LengthDict()
assert type(x) == LengthDict
assert x['word'] == 4
assert x.get('word') is None
assert 5 == eval("a + word", LengthDict())
class Squares(dict):
def __missing__(self, k):
v = k * k
self[k] = v
return v
x = Squares()
assert x[-5] == 25
# An object that hashes to the same value always, and compares equal if any its values match.
class Hashable(object):
def __init__(self, *args):
self.values = args
def __hash__(self):
return 1
def __eq__(self, other):
for x in self.values:
for y in other.values:
if x == y:
return True
return False
x = {}
x[Hashable(1,2)] = 8
assert x[Hashable(1,2)] == 8
assert x[Hashable(3,1)] == 8
x[Hashable(8)] = 19
x[Hashable(19,8)] = 1
assert x[Hashable(8)] == 1
assert len(x) == 2
assert list({'a': 2, 'b': 10}) == ['a', 'b']
x = {}
x['a'] = 2
x['b'] = 10
assert list(x) == ['a', 'b']
y = x.copy()
x['c'] = 12
assert y == {'a': 2, 'b': 10}
y.update({'c': 19, "d": -1, 'b': 12})
assert y == {'a': 2, 'b': 12, 'c': 19, 'd': -1}
y.update(y)
assert y == {'a': 2, 'b': 12, 'c': 19, 'd': -1} # hasn't changed