builtin min() returns wrong result in the following use case where its key argument is specified #135879
Closed as not planned
Description
Bug report
Bug description:
def stem(name:str) -> str:
idx = min(name.find('-'), name.find('^'), key=lambda x: x if x >= 0 else len(name))
return name[:idx]
# The result should be always ABC, but this one fails
# In the min() calling both find() returns -1 that is going to be substituted with 3 by the lamba
# So that we should get min(3,3), instead we get -1
print(stem('ABC'))
print(stem('ABC-DE'))
print(stem('ABC-DE^FGH'))
print(stem('ABC-DE^FGH^JKL'))
print(stem('ABC^FGH^JKL'))
print(stem('ABC^FGH'))According to the docs the key function is applied to each element. So that on the first case we should arrive to min(3,3). I was expecting 3, instead I get -1.
The same result comes out if we pass a collection (a tuple in this case):
min((name.find('-'), name.find('^')), key=lambda x: x if x >= 0 else len(name))Thanks
CPython versions tested on:
3.13
Operating systems tested on:
Windows