Files
bun.sh/test
Claude Bot 7f39a1859d fix(spawn): close libuv pipes before freeing to prevent handle queue corruption (#27063)
On Windows, libuv tracks all handles in the event loop's handle_queue
doubly-linked list. When uv_pipe_init() is called, the pipe is inserted
into this queue. If the pipe's memory is later freed without calling
uv_close() first, the queue retains dangling pointers. Subsequent
handle insertions (e.g. during Bun.spawn()) crash when traversing the
corrupted linked list.

Three sites were freeing pipe handles without uv_close:

1. process.zig WindowsSpawnOptions.Stdio.deinit(): When spawn failed,
   already-initialized pipes were freed without uv_close(). Now checks
   pipe.loop to determine if the pipe was registered with the event
   loop, and calls uv_close() if so.

2. process.zig spawnProcessWindows IPC handling: Unsupported IPC pipes
   in stdin/stdout/stderr were freed directly. Now uses the same safe
   close-then-destroy pattern.

3. source.zig openPipe(): If pipe.open(fd) failed after pipe.init()
   succeeded, the pipe was destroyed directly. Now calls uv_close()
   with a callback that frees the memory.

Additionally, pipe allocations in stdio.zig are now zeroed so that the
loop field is reliably null before uv_pipe_init, enabling the init
detection in deinit.

Co-Authored-By: Claude <noreply@anthropic.com>
2026-02-16 14:06:46 +00:00
..
2026-01-18 14:07:30 -08:00
2026-01-07 23:39:10 -08:00
2025-09-30 05:26:32 -07:00

Tests

Finding tests

Tests are located in the test/ directory and are organized using the following structure:

  • test/
    • js/ - tests for JavaScript APIs.
    • cli/ - tests for commands, configs, and stdout.
    • bundler/ - tests for the transpiler/bundler.
    • regression/ - tests that reproduce a specific issue.
    • harness.ts - utility functions that can be imported from any test.

The tests in test/js/ directory are further categorized by the type of API.

  • test/js/
    • bun/ - tests for Bun-specific APIs.
    • node/ - tests for Node.js APIs.
    • web/ - tests for Web APIs, like fetch().
    • first_party/ - tests for npm packages that are built-in, like undici.
    • third_party/ - tests for npm packages that are not built-in, but are popular, like esbuild.

Running tests

To run a test, use Bun's built-in test command: bun test.

bun test # Run all tests
bun test js/bun # Only run tests in a directory
bun test sqlite.test.ts # Only run a specific test

If you encounter lots of errors, try running bun install, then trying again.

Writing tests

Tests are written in TypeScript (preferred) or JavaScript using Jest's describe(), test(), and expect() APIs.

import { describe, test, expect } from "bun:test";
import { gcTick } from "harness";

describe("TextEncoder", () => {
  test("can encode a string", async () => {
    const encoder = new TextEncoder();
    const actual = encoder.encode("bun");
    await gcTick();
    expect(actual).toBe(new Uint8Array([0x62, 0x75, 0x6E]));
  });
});

If you are fixing a bug that was reported from a GitHub issue, remember to add a test in the test/regression/ directory.

// test/regression/issue/02005.test.ts

import { it, expect } from "bun:test";

it("regex literal should work with non-latin1", () => {
  const text = "这是一段要替换的文字";
  expect(text.replace(new RegExp("要替换"), "")).toBe("这是一段的文字");
  expect(text.replace(/要替换/, "")).toBe("这是一段的文字");
});

In the future, a bot will automatically close or re-open issues when a regression is detected or resolved.

Zig tests

These tests live in various .zig files throughout Bun's codebase, leveraging Zig's builtin test keyword.

Currently, they're not run automatically nor is there a simple way to run all of them. We will make this better soon.

TypeScript

Test files should be written in TypeScript. The types in packages/bun-types should be updated to support all new APIs. Changes to the .d.ts files in packages/bun-types will be immediately reflected in test files; no build step is necessary.

Writing a test will often require using invalid syntax, e.g. when checking for errors when an invalid input is passed to a function. TypeScript provides a number of escape hatches here.

  • // @ts-expect-error - This should be your first choice. It tells TypeScript that the next line should fail typechecking.
  • // @ts-ignore - Ignore the next line entirely.
  • // @ts-nocheck - Put this at the top of the file to disable typechecking on the entire file. Useful for autogenerated test files, or when ignoring/disabling type checks an a per-line basis is too onerous.