Suppressions

Este conteúdo não está disponível em sua língua ainda.

The Biome analyzer is the foundation of the linter and assist; in fact, both tools share a lot of similarities.

Among them, they share the same suppression engine, which means that you can suppress a lint rule the same way you would suppress an assist action.

With suppression, it’s possible to turn off a lint rule (or action) for a specific line of code, a range, or the entire file.

Suppression is achievable with suppression comments.

Suppression syntax

Suppression comments have the following format:

1
// biome-ignore lint: <explanation>
2
// biome-ignore assist: <explanation>
3
// biome-ignore syntax: <explanation>
4
// biome-ignore lint/suspicious: <explanation>
5
// biome-ignore lint/suspicious/noDebugger: <explanation>
6
// biome-ignore lint/suspicious/noDebugger(foo): <explanation>
7
// biome-ignore-all lint: <explanation>
8
// biome-ignore-start lint: <explanation>
9
// biome-ignore-end lint: <explanation>

Let’s break it down:

biome-ignore, biome-ignore-all, biome-ignore-start and biome-ignore-end are the start of a suppression comment.
After the space follows the category of the suppression comment. It can be lint, assist, or syntax.
The category is followed by an optional group, or group and name, separated by slashes. For example, /suspicious or /suspicious/noDebugger. The more you specify, the more specific (i.e. targeted) your suppression is.
Some rules even allow you to specify values during suppression. These can be specified between parentheses, for example: (foo). Refer to the rule documentation to see whether a rule supports suppression with values.
<explanation> explanation why the rule is disabled.

If you’re unsure of the exact category of a rule/action, you can refer to their documentation page and use their diagnostic category.

Inline suppressions

They disable a lint rule for the next line of code.

In the following example, the suppression comment biome-ignore lint/suspicious/noDebugger: reason will disable the debugger; statement at line 2, but the debugger at line 3 will still raise a diagnostic:

1
// biome-ignore lint/suspicious/noDebugger: reason
2
debugger;
3
debugger;

Top-level suppressions

They disable a lint rule for an entire file. They must be placed at the top of the file, and they must start with biome-ignore-all.

These suppression comments are very useful when you want to suppression some lint rule for a particular file, and you don’t want to rely on a single configuration override to achieve that.

In the following example, the suppression comment biome-ignore-all lint/suspicious/noDebugger: reason will disable the lint rule for all lines in generated.js:

1
// biome-ignore-all lint/suspicious/noDebugger: reason
2

3
debugger
4
debugger

When a top-level suppression comment isn’t at the top of the file, it is considered unused and Biome will emit a diagnostic with category suppression/unused.

Range suppressions

They disable a lint rule from a particular range in the file, starting from the line with the start comment, until the line with the end comment.

To mark the beginning of a range suppression, the suppression comment must start with // biome-ignore-start. To mark the end of it, the suppression comment must start with // biome-ignore-end.

The following example will disable the rule lint/suspicious/noDoubleEquals for line 2 and 3, but line 5 will raise a diagnostic:

1
// biome-ignore-start lint/suspicious/noDoubleEquals: reason
2
a == b;
3
c == d;
4
// biome-ignore-end lint/suspicious/noDoubleEquals: reason
5
f == g;

Range suppressions can also overlap. Consider the following example:

1
debugger;
2
// biome-ignore-start lint/suspicious/noDebugger: reason
3
debugger
4
// biome-ignore-start lint/suspicious/noDoubleEquals: reason
5
a == b;
6
c == d;
7
// biome-ignore-end lint/suspicious/noDoubleEquals: reason
8
debugger
9
f == g;
10
// biome-ignore-end lint/suspicious/noDebugger: reason

In the above code:

The debugger statement at line 1 will raise a diagnostic because there’s no suppression comment that disables it.
The comment // biome-ignore-start lint/suspicious/noDebugger: reason at line 2 starts disabling noDebugger from line 3 onwards.
The comment // biome-ignore-start lint/suspicious/noDoubleEquals: reason at line 4 starts disabling noDoubleEquals from line 5 onwards.
The comment // biome-ignore-end lint/suspicious/noDoubleEquals: reason at line 7 terminates the suppression of noDoubleEquals that was started by the suppression comment at line 4.
The debugger statement at line 8 doesn’t raise diagnostics due to the suppression comment at line 2.
The f == g statement raises a diagnostic because the rule noDoubleEquals isn’t suppressed anymore.
The comment // biome-ignore-end lint/suspicious/noDebugger: reason at line 7 terminates the suppression of noDebugger that was started by the suppression comment at line 2.