useConsistentTestIt

JavaScript (and super languages)

Caution

This rule is part of the nursery group. This means that it is experimental and the behavior can change at any time.

Summary

• Rule available since: v2.4.11
• Diagnostic Category: lint/nursery/useConsistentTestIt
• This rule has a safe fix.
• The default severity of this rule is warning.
• This rule belongs to the following domains:
  • test
• Sources:
  • Inspired from jest/consistent-test-it
  • Inspired from vitest/consistent-test-it

How to configure

biome.json

{
  "linter": {
    "rules": {
      "nursery": {
        "useConsistentTestIt": "error"
      }
    }
  }
}

Description

Enforce consistent use of it or test for test functions.

it and test are aliases for the same function in most test frameworks. This rule enforces using one over the other for consistency.

Examples

Invalid

test("foo", () => {});

code-block.js:1:1 lint/nursery/useConsistentTestIt  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ The test function test is inconsistent with the configured preferred function it.
  
  > 1 │ test(“foo”, () => {});
      │ ^^^^
    2 │ 
  
  ℹ Using a consistent function for tests improves readability and makes it easier to search for tests in the codebase.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Safe fix: Use it instead.
  
    1   │ - test(“foo”,·()·=>·{});
      1 │ + it(“foo”,·()·=>·{});
    2 2 │   
  

Valid

it("foo", () => {});

Options

function

The function to use for top-level tests (outside describe blocks). Accepted values are:

• "it" (default): Enforce using it() for top-level tests
• "test": Enforce using test() for top-level tests

biome.json

{
  "linter": {
    "rules": {
      "nursery": {
        "useConsistentTestIt": {
          "options": {
            "function": "test"
          }
        }
      }
    }
  }
}

Invalid

it("foo", () => {});

code-block.js:1:1 lint/nursery/useConsistentTestIt  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ The test function it is inconsistent with the configured preferred function test.
  
  > 1 │ it(“foo”, () => {});
      │ ^^
    2 │ 
  
  ℹ Using a consistent function for tests improves readability and makes it easier to search for tests in the codebase.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Safe fix: Use test instead.
  
    1   │ - it(“foo”,·()·=>·{});
      1 │ + test(“foo”,·()·=>·{});
    2 2 │   
  

Valid

test("foo", () => {});

withinDescribe

The function to use for tests inside describe blocks. Accepted values are:

• "it" (default): Enforce using it() inside describe blocks
• "test": Enforce using test() inside describe blocks

biome.json

{
  "linter": {
    "rules": {
      "nursery": {
        "useConsistentTestIt": {
          "options": {
            "withinDescribe": "test"
          }
        }
      }
    }
  }
}

Invalid

describe("suite", () => {
    it("foo", () => {});
});

code-block.js:2:5 lint/nursery/useConsistentTestIt  FIXABLE  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━

  ⚠ The test function it is inconsistent with the configured preferred function test.
  
    1 │ describe(“suite”, () => {
  > 2 │     it(“foo”, () => {});
      │     ^^
    3 │ });
    4 │ 
  
  ℹ Using a consistent function for tests improves readability and makes it easier to search for tests in the codebase.
  
  ℹ This rule belongs to the nursery group, which means it is not yet stable and may change in the future. Visit https://biomejs.dev/linter/#nursery for more information.
  
  ℹ Safe fix: Use test instead.
  
    1 1 │   describe(“suite”, () => {
    2   │ - ····it(“foo”,·()·=>·{});
      2 │ + ····test(“foo”,·()·=>·{});
    3 3 │   });
    4 4 │   
  

Valid

describe("suite", () => {
    test("foo", () => {});
});

Related links

• Disable a rule
• Configure the code fix
• Rule options
• Source Code
• Test Cases