scrapy/tests/test_item.py

302 lines
8.3 KiB
Python

from abc import ABCMeta
from unittest import mock
import pytest
from scrapy.item import Field, Item, ItemMeta
class TestItem:
def assertSortedEqual(self, first, second, msg=None):
assert sorted(first) == sorted(second), msg
def test_simple(self):
class TestItem(Item):
name = Field()
i = TestItem()
i["name"] = "name"
assert i["name"] == "name"
def test_init(self):
class TestItem(Item):
name = Field()
i = TestItem()
with pytest.raises(KeyError):
i["name"]
i2 = TestItem(name="john doe")
assert i2["name"] == "john doe"
i3 = TestItem({"name": "john doe"})
assert i3["name"] == "john doe"
i4 = TestItem(i3)
assert i4["name"] == "john doe"
with pytest.raises(KeyError):
TestItem({"name": "john doe", "other": "foo"})
def test_invalid_field(self):
class TestItem(Item):
pass
i = TestItem()
with pytest.raises(KeyError):
i["field"] = "text"
with pytest.raises(KeyError):
i["field"]
def test_repr(self):
class TestItem(Item):
name = Field()
number = Field()
i = TestItem()
i["name"] = "John Doe"
i["number"] = 123
itemrepr = repr(i)
assert itemrepr == "{'name': 'John Doe', 'number': 123}"
i2 = eval(itemrepr) # pylint: disable=eval-used
assert i2["name"] == "John Doe"
assert i2["number"] == 123
def test_private_attr(self):
class TestItem(Item):
name = Field()
i = TestItem()
i._private = "test"
assert i._private == "test"
def test_raise_getattr(self):
class TestItem(Item):
name = Field()
i = TestItem()
with pytest.raises(AttributeError):
i.name
def test_raise_setattr(self):
class TestItem(Item):
name = Field()
i = TestItem()
with pytest.raises(AttributeError):
i.name = "john"
def test_custom_methods(self):
class TestItem(Item):
name = Field()
def get_name(self):
return self["name"]
def change_name(self, name):
self["name"] = name
i = TestItem()
with pytest.raises(KeyError):
i.get_name()
i["name"] = "lala"
assert i.get_name() == "lala"
i.change_name("other")
assert i.get_name() == "other"
def test_metaclass(self):
class TestItem(Item):
name = Field()
keys = Field()
values = Field()
i = TestItem()
i["name"] = "John"
assert list(i.keys()) == ["name"]
assert list(i.values()) == ["John"]
i["keys"] = "Keys"
i["values"] = "Values"
self.assertSortedEqual(list(i.keys()), ["keys", "values", "name"])
self.assertSortedEqual(list(i.values()), ["Keys", "Values", "John"])
def test_metaclass_with_fields_attribute(self):
class TestItem(Item):
fields = {"new": Field(default="X")}
item = TestItem(new="New")
self.assertSortedEqual(list(item.keys()), ["new"])
self.assertSortedEqual(list(item.values()), ["New"])
def test_metaclass_inheritance(self):
class ParentItem(Item):
name = Field()
keys = Field()
values = Field()
class TestItem(ParentItem):
keys = Field()
i = TestItem()
i["keys"] = 3
assert list(i.keys()) == ["keys"]
assert list(i.values()) == [3]
def test_metaclass_multiple_inheritance_simple(self):
class A(Item):
fields = {"load": Field(default="A")}
save = Field(default="A")
class B(A):
pass
class C(Item):
fields = {"load": Field(default="C")}
save = Field(default="C")
class D(B, C):
pass
item = D(save="X", load="Y")
assert item["save"] == "X"
assert item["load"] == "Y"
assert D.fields == {"load": {"default": "A"}, "save": {"default": "A"}}
# D class inverted
class E(C, B):
pass
assert E(save="X")["save"] == "X"
assert E(load="X")["load"] == "X"
assert E.fields == {"load": {"default": "C"}, "save": {"default": "C"}}
def test_metaclass_multiple_inheritance_diamond(self):
class A(Item):
fields = {"update": Field(default="A")}
save = Field(default="A")
load = Field(default="A")
class B(A):
pass
class C(A):
fields = {"update": Field(default="C")}
save = Field(default="C")
class D(B, C):
fields = {"update": Field(default="D")}
load = Field(default="D")
assert D(save="X")["save"] == "X"
assert D(load="X")["load"] == "X"
assert D.fields == {
"save": {"default": "C"},
"load": {"default": "D"},
"update": {"default": "D"},
}
# D class inverted
class E(C, B):
load = Field(default="E")
assert E(save="X")["save"] == "X"
assert E(load="X")["load"] == "X"
assert E.fields == {
"save": {"default": "C"},
"load": {"default": "E"},
"update": {"default": "C"},
}
def test_metaclass_multiple_inheritance_without_metaclass(self):
class A(Item):
fields = {"load": Field(default="A")}
save = Field(default="A")
class B(A):
pass
class C:
fields = {"load": Field(default="C")}
not_allowed = Field(default="not_allowed")
save = Field(default="C")
class D(B, C):
pass
with pytest.raises(KeyError):
D(not_allowed="value")
assert D(save="X")["save"] == "X"
assert D.fields == {"save": {"default": "A"}, "load": {"default": "A"}}
# D class inverted
class E(C, B):
pass
with pytest.raises(KeyError):
E(not_allowed="value")
assert E(save="X")["save"] == "X"
assert E.fields == {"save": {"default": "A"}, "load": {"default": "A"}}
def test_to_dict(self):
class TestItem(Item):
name = Field()
i = TestItem()
i["name"] = "John"
assert dict(i) == {"name": "John"}
def test_copy(self):
class TestItem(Item):
name = Field()
item = TestItem({"name": "lower"})
copied_item = item.copy()
assert id(item) != id(copied_item)
copied_item["name"] = copied_item["name"].upper()
assert item["name"] != copied_item["name"]
def test_deepcopy(self):
class TestItem(Item):
tags = Field()
item = TestItem({"tags": ["tag1"]})
copied_item = item.deepcopy()
item["tags"].append("tag2")
assert item["tags"] != copied_item["tags"]
class TestItemMeta:
def test_new_method_propagates_classcell(self):
new_mock = mock.Mock(side_effect=ABCMeta.__new__)
base = ItemMeta.__bases__[0]
with mock.patch.object(base, "__new__", new_mock):
class MyItem(Item):
def f(self):
# For rationale of this see:
# https://github.com/python/cpython/blob/ee1a81b77444c6715cbe610e951c655b6adab88b/Lib/test/test_super.py#L222
return __class__
MyItem()
(first_call, second_call) = new_mock.call_args_list[-2:]
*_, attrs = first_call[0]
assert "__classcell__" not in attrs
*_, attrs = second_call[0]
assert "__classcell__" in attrs
class TestItemMetaClassCellRegression:
def test_item_meta_classcell_regression(self):
class MyItem(Item, metaclass=ItemMeta):
def __init__(self, *args, **kwargs): # pylint: disable=useless-parent-delegation
# This call to super() trigger the __classcell__ propagation
# requirement. When not done properly raises an error:
# TypeError: __class__ set to <class '__main__.MyItem'>
# defining 'MyItem' as <class '__main__.MyItem'>
super().__init__(*args, **kwargs)