joythief.data_structures module

class joythief.data_structures.DictContaining(**kwargs: Any)

class joythief.data_structures.DictContaining(content: Mapping[Hashable, Any], /, **kwargs: Any)

class joythief.data_structures.DictContaining(content: Iterable[tuple[Hashable, Any]], /, **kwargs: Any)

Bases: Matcher[Mapping[Hashable, Any]], dict[Hashable, Any]

Match the specified keys in a mapping, ignoring any extra keys.

Parameters:

• content (Any) – mapping or iterable of key-value pairs to include in the comparison

• **kwargs (Any) – additional key-value pairs to include in the comparison

Raises:

ValueError – if no keys are specified (use InstanceOf with dict instead).

Added in version 0.7.0.

Changed in version 0.8.0: added optionally().

assert (
    actual
    == DictContaining([("foo", 123), ("bar", 456)], baz=InstanceOf(int))
)

Note: this subclasses dict so that pytest will show the common and differing items. After a single comparison with a mapping, any keys that exist in the mapping but that are not specified in the matcher will appear to be in the matcher, with the same value. For example:

>       assert DictContaining(foo=123, bar=0, baz=789) == dict(foo=123, bar=456, qux=999)
E       AssertionError: assert DictContainin..., 'baz': 789}) == {'bar': 456, ...3, 'qux': 999}
E
E         Omitting 2 identical items, use -vv to show
E         Differing items:
E         {'bar': 0} != {'bar': 456}
E         Left contains 1 more item:
E         {'baz': 789}
E         Use -v to get more diff

static optionally(value)

Matcher factory for keys that may not be present.

assert (
    actual
    == DictContaining(foo=DictContaining.optionally(123))
)

Note: this allows keys to be missing entirely, but matches the value strictly. For the equivalent of typing.Optional, use Nullable. These can be combined if required, e.g. to allow the key "foo" to be either: missing; present with the value 123; or present with the value None, use:

assert (
    actual
    == DictContaining(foo=DictContaining.optionally(Nullable(123)))
)

Parameters:

value (T | Matcher[T])

Return type:

T | Matcher[T]