New challenges

Author: laike9m

challenges/advanced-decorator/question.py

@@ -0,0 +1,27 @@
+"""
+TODO:
+
+Define a decorator that wraps a function and returns a function with the same signature.
+The decorator takes an argument `message` of type string
+"""
+
+
+def decorator(message):
+    ...
+
+
+## End of your code ##
+@decorator(message="x")
+def foo(a: int, *, b: str) -> None:
+    ...
+
+
+@decorator  # expect-type-error
+def bar(a: int, *, b: str) -> None:
+    ...
+
+
+foo(1, b="2")
+foo(1, "2")  # expect-type-error
+foo(a=1, e="2")  # expect-type-error
+decorator(1)  # expect-type-error

challenges/advanced-decorator/solution.py

@@ -0,0 +1,37 @@
+"""
+TODO:
+
+Define a decorator that wraps a function and returns a function with the same signature.
+The decorator takes an argument `message` of type string
+"""
+from typing import TypeVar
+from collections.abc import Callable
+
+# Python < 3.12
+#
+# T = TypeVar("T", bound=Callable)
+#
+# def decorator(func: T) -> T:
+#     return func
+
+
+# Python >= 3.12
+def decorator[T: Callable](message: str) -> Callable[[T], T]:
+    ...
+
+
+## End of your code ##
+@decorator(message="x")
+def foo(a: int, *, b: str) -> None:
+    ...
+
+
+@decorator  # expect-type-error
+def bar(a: int, *, b: str) -> None:
+    ...
+
+
+foo(1, b="2")
+foo(1, "2")  # expect-type-error
+foo(a=1, e="2")  # expect-type-error
+decorator(1)  # expect-type-error

challenges/advanced-typeshed/question.py

@@ -0,0 +1,27 @@
+"""
+TODO:
+
+Annotate class `MyContainer`, which should support item access, i.e.
+using `[x]` to get, set, and delete an item.
+
+HINT: Use https://github.com/python/typeshed
+"""
+
+
+class MyContainer:
+    ...
+
+
+## End of your code ##
+from typing import assert_type
+from collections.abc import Mapping
+
+c = MyContainer()
+c[1] = 1
+c["2"] = 2
+print(c[1])
+print(c["2"])
+del c[1]
+del c["2"]
+assert_type(c, dict)  # expect-type-error
+assert_type(c, Mapping)  # expect-type-error

challenges/advanced-typeshed/solution.py

@@ -0,0 +1,29 @@
+"""
+TODO:
+
+Annotate class `MyContainer`, which should support item access, i.e.
+using `[x]` to get, set, and delete an item.
+
+HINT: Use https://github.com/python/typeshed
+"""
+
+from _typeshed import SupportsItemAccess
+
+
+class MyContainer(SupportsItemAccess):
+    ...
+
+
+## End of your code ##
+from typing import assert_type
+from collections.abc import Mapping
+
+c = MyContainer()
+c[1] = 1
+c["2"] = 2
+print(c[1])
+print(c["2"])
+del c[1]
+del c["2"]
+assert_type(c, dict)  # expect-type-error
+assert_type(c, Mapping)  # expect-type-error

challenges/basic-typealias/question.py

@@ -0,0 +1,15 @@
+"""
+TODO:
+
+Create a new type called Vector, which is a list of float.
+"""
+
+
+## End of your code ##
+def foo(v: Vector):
+    ...
+
+
+foo([1.1, 2])
+foo(1)  # expect-type-error
+foo(["1"])  # expect-type-error

challenges/basic-typealias/solution.py

@@ -0,0 +1,22 @@
+"""
+TODO:
+
+Create a new type called Vector, which is a list of float.
+"""
+
+from typing import TypeAlias
+
+Vector: TypeAlias = list[float]
+
+# Python >= 3.12
+# type Vector = list[float]
+
+
+## End of your code ##
+def foo(v: Vector):
+    ...
+
+
+foo([1.1, 2])
+foo(1)  # expect-type-error
+foo(["1"])  # expect-type-error