Suppression

Rules can also be ignored in specific locations in your code (instead of disabling the rule entirely) to silence false positives or permissible violations.

Note

To disable a rule entirely, set it to the ignore level as described in rule levels.

ty suppression comments

To suppress a rule violation inline add a # ty: ignore[<rule>] comment at the end of the line:

a = 10 + "test"  # ty: ignore[unsupported-operator]

Rule violations spanning multiple lines can be suppressed by adding the comment at the end of the violation's first or last line:

def sum_three_numbers(a: int, b: int, c: int) -> int: ...

# on the first line

sum_three_numbers(  # ty: ignore[missing-argument]
    3,
    2
)

# or, on the last line

sum_three_numbers(
    3,
    2
)  # ty: ignore[missing-argument]

To suppress multiple violations on a single line, enumerate each rule separated by a comma:

sum_three_numbers("one", 5)  # ty: ignore[missing-argument, invalid-argument-type]

To suppress specific rules for an entire file, place a # ty: ignore[<rule>] comment on its own line before any Python code:

# ty: ignore[invalid-argument-type]

sum_three_numbers(3, 2, "1")

Note

Enumerating rule names (e.g., [rule1, rule2]) is optional. However, we strongly recommend including suppressing specific rules to avoid accidental suppression of other errors.

Standard suppression comments

ty supports the standard type: ignore comment format introduced by PEP 484.

type: ignore suppresses all violations on that line.

type: ignore[ty:<rule>] behaves like ty: ignore[<rule>] and only suppresses the matching rule. Codes without a ty: prefix are ignored, which makes it possible to combine suppressions for multiple type checkers in a single comment.

# Ignore all typing errors on the next line
sum_three_numbers("one", 5)  # type: ignore

# Ignore a mypy code and a ty rule in the same comment
sum_three_numbers("one", 5, 2)  # type: ignore[arg-type, ty:invalid-argument-type]

Multiple suppressions comments

To suppress a typing error on a line that already has a suppression comment from another tool, add the # ty: ignore comment to the same line.

For example, to suppress a type error and disable formatting for a specific line:

result = calculate()  # ty: ignore[invalid-argument-type]  # fmt: skip

# or
result = calculate()  # fmt: off  # ty: ignore[invalid-argument-type]

Unused suppression comments

If the unused-ignore-comment rule is enabled, ty will report unused ty: ignore and type: ignore comments.

unused-ignore-comment violations can only be suppressed using # ty: ignore[unused-ignore-comment]. They cannot be suppressed using # ty: ignore without a rule code or # type: ignore.

@no_type_check directive

ty supports the @no_type_check decorator to suppress all violations inside a function.

from typing import no_type_check

def sum_three_numbers(a: int, b: int, c: int) -> int:
    return a + b + c

@no_type_check
def main():
    sum_three_numbers(1, 2)  # no error for the missing argument

Decorating a class with @no_type_check isn't supported.