---
title: Bun
description: Learn how to integrate Allure with Bun to generate rich, interactive test reports. Follow step-by-step setup, test execution, and report generation guidance.
---

# Getting started with Allure Bun

[![Allure Bun npm latest version](https://img.shields.io/npm/v/allure-bun?style=flat "Allure Bun npm latest version")](https://www.npmjs.com/package/allure-bun)

Generate beautiful HTML reports using [Allure Report](https://allurereport.org/docs/) and your [Bun](https://bun.sh/docs/cli/test) tests.

Info:
Check out the example projects at [github.com/allure-examples](https://github.com/orgs/allure-examples/repositories?q=visibility%3Apublic+archived%3Afalse+topic%3Aexample+topic%3Abun) to see Allure Bun in action.

## Setting up

### 1. Prepare your project

1. Make sure [Bun](https://bun.sh/) is installed.

1. Open a terminal and go to the project directory. For example:

   ```bash
   cd /home/user/myproject
   ```

1. Make sure Allure Report is installed. If it's not, follow the [installation instructions](/docs/v2/install/). Note that Allure Report requires Java.

1. Install the Allure Bun integration:

   **npm:**
   ```bash
   npm install --save-dev allure-bun allure-js-commons
   ```

   **yarn:**
   ```bash
   yarn add --dev allure-bun allure-js-commons
   ```

   **pnpm:**
   ```bash
   pnpm install --dev allure-bun allure-js-commons
   ```

   **bun:**
   ```bash
   bun add --dev allure-bun allure-js-commons
   ```

   Keep `allure-bun` and `allure-js-commons` on the same version.

1. Add the preload entry to your `bunfig.toml`:

   ```toml
   [test]
   preload = ["allure-bun/setup"]
   ```

   This registers the integration before any test files are loaded. Your test files themselves do not need any changes — keep using `bun:test` as usual.

   Optionally, specify `resultsDir` and other options. See [Allure Bun configuration](/docs/bun-configuration/) for more details.

### 2. Run tests

Run your Bun tests the same way you would run them usually:

```bash
bun test
```

This will save the necessary data into `allure-results` or another directory, according to the [configuration](/docs/bun-configuration/). If the directory already exists, new files will be added to the existing ones so that a future report will be based on them all.

Warning:
Running tests with `--concurrent` or `--randomize` is not supported. Allure Bun will fail fast with a descriptive error if either flag is detected.

All standard `bun:test` modifiers work as usual: `.skip`, `.todo`, `.if()`, `.skipIf()`, `.todoIf()`, and `.each()` — on both `test` and `describe`; plus `.failing` and `.serial` on `test` only. Two exceptions: `test.concurrent` throws an error, and `.only` (on both `test` and `describe`) is not supported — it causes the same queue-ordering error described in the warning below.

### 3. Generate a report

Finally, convert the test results into an HTML report. This can be done by one of two commands:

- `allure generate` processes the test results and saves an HTML report into the `allure-report` directory. To view the report, use the `allure open` command.

- `allure serve` creates the same report as `allure generate`, then automatically opens the main page of the report in a web browser.

## Writing tests

The Allure Bun integration extends the standard reporting features of Bun by providing additional capabilities for crafting more informative and structured tests. This section highlights key enhancements that can be utilized:

- **Metadata Annotation**: Enhance test reports with [descriptions, links, and other metadata](#add-metadata).
- **Test Organization**: Structure your tests into clear hierarchies for better readability and organization, see [organize tests](#organize-tests).
- **Step Division**: Break down tests into smaller [test steps](#divide-a-test-into-steps) for easier understanding and maintenance.
- **Parametrized Tests**: Clearly describe the parameters for [parametrized tests](#describe-parametrized-tests) to specify different scenarios.
- **Set labels globally**: Use [environment variables](#set-labels-globally) to set metadata and other labels.
- **Attachments**: Capture [files and other content](#attach-files) during test execution.
- **Test Selection**: Use a test plan file to [select which tests to run](#select-tests-via-a-test-plan-file), allowing for flexible test execution.
- **Environment Details**: Include comprehensive [environment information](#environment-information) to accompany the test report.

In most cases, Allure Bun provides two different ways to use a feature: the Runtime API and the Metadata API.

Warning: Known limitation: always use `describe()`
Always place tests inside `describe()` blocks. Mixing root-level `test()` calls with `describe()` blocks in the same file produces the error `allure-bun does not support concurrent tests`. This is a known limitation: Bun defers `describe()` callbacks, which causes allure-bun's registration queue to diverge from execution order — the same ordering mechanism it uses to prevent concurrent test execution. `test.skip` and `test.todo` are exempt. Files that contain only root-level tests with no `describe()` blocks are also unaffected.

- **Runtime API**: use Allure's functions to add certain data to the test result during its execution. This approach allows for constructing the data dynamically.

  Note that it is recommended to call Allure's functions as close to the beginning of the test as possible. This way, the data will be added even if the test fails early.

- **Metadata API**: add a metadata tag (beginning with `@`) into the test name. Allure Bun will extract it and update the test result's data accordingly. When using this approach, the data is guaranteed to be added regardless of how the test itself runs.

### Add Metadata

Allure allows you to enrich your reports with a variety of [metadata](/docs/v2/readability/#description-links-and-other-metadata). This additional information provides context and details for each test, enhancing the report's usefulness. Refer to the [metadata reference section](/docs/bun-reference/#metadata) for an exhaustive list of what can be added.

**Runtime API:**
```ts
import * as allure from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test("Test Authentication", async () => {
    await allure.displayName("Test Authentication");
    await allure.owner("John Doe");
    await allure.tags("Web interface", "Authentication");
    await allure.severity("critical");
    // ...
  });
});
```

**Metadata API:**
```ts
import { describe, test } from "bun:test";

describe("authentication", () => {
  test(
    "Test Authentication" +
      " @allure.label.owner:JohnDoe" +
      " @allure.label.tag:WebInterface" +
      " @allure.label.tag:Authentication" +
      " @allure.label.severity:critical",
    async () => {
      // ...
    },
  );
});
```

### Organize tests

As described in [Improving navigation in your test report](/docs/v2/navigation/), Allure supports multiple ways to organize tests into hierarchical structures.

To specify a test's location in the [behavior-based hierarchy](/docs/v2/navigation/#behavior-based-hierarchy):

**Runtime API:**
```ts
import * as allure from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test("Test Authentication", async () => {
    await allure.epic("Web interface");
    await allure.feature("Authentication");
    await allure.story("Login with username");
    // ...
  });
});
```

**Metadata API:**
```ts
import { describe, test } from "bun:test";

describe("authentication", () => {
  test(
    "Test Authentication" +
      " @allure.label.epic:WebInterface" +
      " @allure.label.feature:EssentialFeatures" +
      " @allure.label.story:Authentication",
    async () => {
      // ...
    },
  );
});
```

To specify a test's location in the [suite-based hierarchy](/docs/v2/navigation/#suite-based-hierarchy):

**Runtime API:**
```ts
import * as allure from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test("Test Authentication", async () => {
    await allure.parentSuite("Tests for web interface");
    await allure.suite("Tests for essential features");
    await allure.subSuite("Tests for authentication");
    // ...
  });
});
```

**Metadata API:**
```ts
import { describe, test } from "bun:test";

describe("authentication", () => {
  test(
    "Test Authentication" +
      " @allure.label.parentSuite:TestsForWebInterface" +
      " @allure.label.suite:TestsForEssentialFeatures" +
      " @allure.label.subSuite:TestsForAuthentication",
    async () => {
      // ...
    },
  );
});
```

### Divide a test into steps

To [create steps and sub-steps](/docs/steps/), you can use the `step()` function, see the [reference](/docs/bun-reference/#test-steps).

```ts
import * as allure from "allure-js-commons";
import { Status } from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test("Test Authentication", async () => {
    await allure.step("Step 1", async () => {
      await allure.step("Sub-step 1", async (ctx) => {
        await ctx.parameter("foo", "1");
        // ...
      });
      await allure.step("Sub-step 2", async (ctx) => {
        await ctx.parameter("foo", "2");
        // ...
      });
    });
    await allure.logStep("Step 2", Status.SKIPPED);
  });
});
```

### Describe parametrized tests

Bun's built-in `test.each()` makes it straightforward to implement the [parametrized tests](/docs/v2/readability/#parametrized-tests) pattern. Each row in the table is treated as a separate test run by Allure Report.

To display a parameter value in the test report, pass it to the [`parameter()`](/docs/bun-reference/#parametrized-tests) function.

**Using test():**
```ts
import * as allure from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  for (const login of ["johndoe", "johndoe@example.com"]) {
    test(`Test Authentication as ${login}`, async () => {
      await allure.parameter("login", login);
      await allure.parameter("time", new Date().toUTCString(), { excluded: true });
      // ...
    });
  }
});
```

**Using test.each():**
```ts
import * as allure from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test.each(["johndoe", "johndoe@example.com"])("Test Authentication as %s", async (login) => {
    await allure.parameter("login", login);
    await allure.parameter("time", new Date().toUTCString(), { excluded: true });
    // ...
  });
});
```

### Set labels globally

Any [labels](/docs/bun-reference/#label), including custom ones, can be set via environment variables in your operating system. Here's an example:

**MacOS/Linux:**
```bash
export ALLURE_LABEL_epic=WebInterface
bun test
```

**Windows:**
```powershell
$Env:ALLURE_LABEL_epic = "WebInterface"
bun test
```

### Attach files

In Allure reports, you have the ability to [attach various types of files](/docs/attachments/), which can greatly enhance the comprehensibility of the report.

For detailed instructions on how to implement attachments, refer to the [attachments section in the Allure Bun reference](/docs/bun-reference/#attachments).

```ts
import * as allure from "allure-js-commons";
import { ContentType } from "allure-js-commons";
import { describe, test } from "bun:test";

describe("authentication", () => {
  test("Test Authentication", async () => {
    // ...

    await allure.attachment("Text file", "This is the file content.", ContentType.TEXT);

    await allure.attachmentPath("Screenshot", "/path/to/image.png", {
      contentType: ContentType.PNG,
      fileExtension: "png",
    });
  });
});
```

### Select tests via a test plan file

If the `ALLURE_TESTPLAN_PATH` environment variable is defined and points to an existing file, Bun will only run tests listed in this file.

Here's an example of running tests according to a file named `testplan.json`:

**MacOS/Linux:**
```bash
export ALLURE_TESTPLAN_PATH=testplan.json
bun test
```

**Windows:**
```powershell
$Env:ALLURE_TESTPLAN_PATH = "testplan.json"
bun test
```

### Environment information

For the main page of the report, you can collect various information about the environment in which the tests were executed. To do so, edit the [`environmentInfo`](/docs/bun-configuration/#environmentinfo) object in the configuration.

For example, it is a good idea to record the OS version and the Bun runtime version. This may help the future reader investigate bugs that are reproducible only in some environments.

```ts
// preload.ts
import type { ReporterConfig } from "allure-js-commons/sdk/reporter";
import * as os from "node:os";

globalThis.allureBunConfig = {
  environmentInfo: {
    os_platform: os.platform(),
    os_release: os.release(),
    os_version: os.version(),
    bun_version: Bun.version,
  },
} satisfies ReporterConfig;

await import("allure-bun/setup");
```

```toml
# bunfig.toml
[test]
preload = ["./preload.ts"]
```