feat(vitest): Support projectId in wrapVitest config

[ekeith (evanmkeith)]

Summary

Adds an optional projectId field to the wrapVitest configuration, letting users target a specific Braintrust project by its stable ID instead of by name. When projectId is set, it takes precedence over projectName.

Motivation

Project names can be renamed or collide across orgs. Users who already know the project ID (e.g. from CI config or another integration) had no way to bind Vitest experiments to that exact project. This brings the wrapper in line with init / initExperiment, which both accept projectId.

Changes

• js/src/wrappers/vitest/types.ts — Add projectId?: string to WrapperConfig with a docstring noting precedence over projectName.
• js/src/wrappers/vitest/wrapper.ts — In wrapDescribe's lazy getOrCreateContext, branch on config.projectId:
  • If set, call initExperiment({ projectId, experiment }).
  • Otherwise, preserve the existing initExperiment(projectName ?? suiteName, { experiment }) call (no behavior change for existing users).
• js/src/wrappers/vitest/README.md — Document the new projectId parameter on wrapVitest.
• js/src/wrappers/vitest/vitest-wrapper.test.ts:
  • Update the initExperiment mock to handle both overloads (positional projectName and options object).
  • Add configureNode() at module load so AsyncLocalStorage actually propagates context — required for the new tests' synchronous fake describe factories to exercise experiment creation.
  • Add a Project selection describe block with four tests:
    1. projectId is forwarded to initExperiment.
    2. projectId takes precedence when both projectId and projectName are set.
    3. projectName-only path is unchanged.
    4. Suite-name fallback (no project config) is unchanged.

Usage

import * as vitest from "vitest";
import { wrapVitest } from "braintrust";

const bt = wrapVitest(vitest, {
  projectId: "abc-123-stable-project-id",
});

bt.describe("my suite", () => {
  bt.test("logs to the project by id", async () => {
    /* ... */
  });
});

[Caitlin Pinn (cpinn)]

Thank you for making the change.

[Abhijeet Prasad (AbhiPrasad)]

needs a changeset and we can merge this in!

[Abhijeet Prasad (AbhiPrasad)]

released with https://github.com/braintrustdata/braintrust-sdk-javascript/releases/tag/braintrust%403.11.0!