89 lines
1.9 KiB
Plaintext
89 lines
1.9 KiB
Plaintext
-- Test cases for Python 3.8 features
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[case testWalrus1]
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from typing import Optional
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def foo(x: int) -> Optional[int]:
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if x < 0:
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return None
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return x
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def test(x: int) -> str:
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if (n := foo(x)) is not None:
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return str(x)
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else:
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return "<fail>"
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[file driver.py]
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from native import test
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assert test(10) == "10"
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assert test(-1) == "<fail>"
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[case testWalrus2]
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from typing import Optional, Tuple, List
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class Node:
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def __init__(self, val: int, next: Optional['Node']) -> None:
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self.val = val
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self.next = next
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def pairs(nobe: Optional[Node]) -> List[Tuple[int, int]]:
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if nobe is None:
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return []
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l = []
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while next := nobe.next:
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l.append((nobe.val, next.val))
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nobe = next
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return l
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def make(l: List[int]) -> Optional[Node]:
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cur: Optional[Node] = None
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for x in reversed(l):
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cur = Node(x, cur)
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return cur
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[file driver.py]
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from native import Node, make, pairs
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assert pairs(make([1,2,3])) == [(1,2), (2,3)]
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assert pairs(make([1])) == []
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assert pairs(make([])) == []
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[case testFStrings]
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from datetime import datetime
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def test_fstring_equal_sign() -> None:
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today = datetime(year=2017, month=1, day=27)
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assert f"{today=:%B %d, %Y}" == 'today=January 27, 2017' # using date format specifier and debugging
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foo = "bar"
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assert f"{ foo = }" == " foo = 'bar'" # preserves whitespace
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line = "The mill's closed"
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assert f"{line = }" == 'line = "The mill\'s closed"'
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assert f"{line = :20}" == "line = The mill's closed "
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assert f"{line = !r:20}" == 'line = "The mill\'s closed" '
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[case testMethodOverrideDefaultPosOnly1]
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class Foo:
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def f(self, x: int=20, /, *, z: int=10) -> None:
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pass
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class Bar(Foo):
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def f(self, *args: int, **kwargs: int) -> None:
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print("stuff", args, kwargs)
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z: Foo = Bar()
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z.f(1, z=50)
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z.f()
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z.f(1)
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z.f(z=50)
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[out]
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stuff (1,) {'z': 50}
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stuff () {}
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stuff (1,) {}
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stuff () {'z': 50}
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