Add __contains__, __eq__, and __repr__ to State

[bysiber]

Summary

The State class (used for request.state and app.state) was missing a few commonly expected dunder methods, making it harder to work with in tests and during debugging.

Changes

Added three methods to State:

__contains__

Without this, "key" in state falls back to __iter__, which iterates over all keys in O(n) time. With an explicit __contains__, the lookup delegates to the underlying dict in O(1).

state = State()
state.counter = 0
"counter" in state  # True, O(1or)

__eq__

Allows direct comparison of State objects, which is particularly useful in tests. Returns NotImplemented for non-State comparisons so Python can try the other operand's __eq__.

state1 = State({"a": 1})
state2 = State({"a": 1})
assert state1 == state2

__repr__

Provides a readable representation instead of the default <State object at 0x...>, making debugging significantly easier.

state = State()
state.debug = True
state.counter = 42
repr(state)  # "State(debug=True, counter=42)"