language-servers/ruff
1
0
Fork 0
mirror of https://github.com/astral-sh/ruff.git synced 2025-09-28 12:55:05 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions 2
ruff/crates/red_knot_python_semantic/resources/mdtest/subscript/string.md
David Peter 15394a8028
[red-knot] MDTests: Do not depend on precise public-symbol type inference (#15691) 
## Summary

Another small PR to focus #15674 solely on the relevant changes. This
makes our Markdown tests less dependent on precise types of public
symbols, without actually changing anything semantically in these tests.

Best reviewed using ignore-whitespace-mode.

## Test Plan

Tested these changes on `main` and on the branch from #15674.
2025-01-23 13:51:33 +00:00

3.2 KiB
Raw Blame History

String subscripts

Indexing

s = "abcde"

reveal_type(s[0])  # revealed: Literal["a"]
reveal_type(s[1])  # revealed: Literal["b"]
reveal_type(s[-1])  # revealed: Literal["e"]
reveal_type(s[-2])  # revealed: Literal["d"]

reveal_type(s[False])  # revealed: Literal["a"]
reveal_type(s[True])  # revealed: Literal["b"]

a = s[8]  # error: [index-out-of-bounds] "Index 8 is out of bounds for string `Literal["abcde"]` with length 5"
reveal_type(a)  # revealed: Unknown

b = s[-8]  # error: [index-out-of-bounds] "Index -8 is out of bounds for string `Literal["abcde"]` with length 5"
reveal_type(b)  # revealed: Unknown

def _(n: int):
    a = "abcde"[n]
    # TODO: Support overloads... Should be `str`
    reveal_type(a)  # revealed: @Todo(return type)

Slices

def _(m: int, n: int, s2: str):
    s = "abcde"

    reveal_type(s[0:0])  # revealed: Literal[""]
    reveal_type(s[0:1])  # revealed: Literal["a"]
    reveal_type(s[0:2])  # revealed: Literal["ab"]
    reveal_type(s[0:5])  # revealed: Literal["abcde"]
    reveal_type(s[0:6])  # revealed: Literal["abcde"]
    reveal_type(s[1:3])  # revealed: Literal["bc"]

    reveal_type(s[-3:5])  # revealed: Literal["cde"]
    reveal_type(s[-4:-2])  # revealed: Literal["bc"]
    reveal_type(s[-10:10])  # revealed: Literal["abcde"]

    reveal_type(s[0:])  # revealed: Literal["abcde"]
    reveal_type(s[2:])  # revealed: Literal["cde"]
    reveal_type(s[5:])  # revealed: Literal[""]
    reveal_type(s[:2])  # revealed: Literal["ab"]
    reveal_type(s[:0])  # revealed: Literal[""]
    reveal_type(s[:2])  # revealed: Literal["ab"]
    reveal_type(s[:10])  # revealed: Literal["abcde"]
    reveal_type(s[:])  # revealed: Literal["abcde"]

    reveal_type(s[::-1])  # revealed: Literal["edcba"]
    reveal_type(s[::2])  # revealed: Literal["ace"]
    reveal_type(s[-2:-5:-1])  # revealed: Literal["dcb"]
    reveal_type(s[::-2])  # revealed: Literal["eca"]
    reveal_type(s[-1::-3])  # revealed: Literal["eb"]

    reveal_type(s[None:2:None])  # revealed: Literal["ab"]
    reveal_type(s[1:None:1])  # revealed: Literal["bcde"]
    reveal_type(s[None:None:None])  # revealed: Literal["abcde"]

    start = 1
    stop = None
    step = 2
    reveal_type(s[start:stop:step])  # revealed: Literal["bd"]

    reveal_type(s[False:True])  # revealed: Literal["a"]
    reveal_type(s[True:3])  # revealed: Literal["bc"]

    s[0:4:0]  # error: [zero-stepsize-in-slice]
    s[:4:0]  # error: [zero-stepsize-in-slice]
    s[0::0]  # error: [zero-stepsize-in-slice]
    s[::0]  # error: [zero-stepsize-in-slice]

    substring1 = s[m:n]
    # TODO: Support overloads... Should be `LiteralString`
    reveal_type(substring1)  # revealed: @Todo(return type)

    substring2 = s2[0:5]
    # TODO: Support overloads... Should be `str`
    reveal_type(substring2)  # revealed: @Todo(return type)

Unsupported slice types

# TODO: It would be great if we raised an error here. This can be done once
# we have support for overloads and generics, and once typeshed has a more
# precise annotation for `str.__getitem__`, that makes use of the generic
# `slice[..]` type. We could then infer `slice[str, str]` here and see that
# it doesn't match the signature of `str.__getitem__`.
"foo"["bar":"baz"]