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noImportCycles

Summary

Section titled Summary

Description

Section titled Description

Prevent import cycles.

This rule warns when a file imports another file that, either directly or indirectly, imports the original file again.

Cycles can lead to symbols that are unexpectedly undefined and are generally considered poor code hygiene.

If a cycle is detected, it is advised to move code such that imports only go in a single direction, i.e. they don’t point “back” to the importing file.

Examples

Section titled Examples

Invalid

Section titled Invalid

foobar.js

import { baz } from "./baz.js";


export function foo() {
    baz();
}


export function bar() {
    console.log("foobar");
}

baz.js

import { bar } from "./foobar.js";


export function baz() {
    bar();
}

Valid

Section titled Valid

foo.js

import { baz } from "./baz.js";


export function foo() {
    baz();
}

bar.js

export function bar() {
    console.log("foobar");
}

baz.js

import { bar } from "./bar.js";


export function baz() {
    bar();
}

How to configure

Section titled How to configure
biome.json
{
  "linter": {
    "rules": {
      "nursery": {
        "noImportCycles": "error"
      }
    }
  }
}
Section titled Related links