feat(jest-config): add `defineConfig` and `mergeConfig` functions by ahnpnl · Pull Request #15844 · jestjs/jest

ahnpnl · 2025-09-30T09:49:25Z

Summary

Inspired from Vite and Playwright, this PR introduces 2 new functions to jest-config: defineConfig and mergeConfig.

This will greatly improve DX that developers:

Don't need to know which interface to use
Get autocomplete OOTB
Don't need to use JSDOC comment for types

Test plan

Added unit tests and e2e tests
Green CI

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commit: 4f7105c

ahnpnl · 2025-09-30T13:31:25Z

Hi @cpojer @SimenB would you pls help me to check this PR? Thank you 🙏

To start Jest doc, we need to run `fetchSupporters` first otherwise it's not possible to start doc server

SimenB · 2025-10-10T12:42:36Z

Yes, love this! I actually thought about this yesterday after seeing ESLint has added the same 👍

SimenB

thank you!

website/package.json

github-actions · 2025-11-11T00:12:45Z

This pull request has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs.
Please note this issue tracker is not a help forum. We recommend using StackOverflow or our discord channel for questions.

ahnpnl force-pushed the feat/config-utils branch 3 times, most recently from 3496223 to 565fc14 Compare September 30, 2025 13:10

ahnpnl marked this pull request as ready for review September 30, 2025 13:30

ahnpnl added 2 commits October 9, 2025 20:10

feat(config): add defineConfig and mergeConfig functions

ae07875

docs(infra): simplify doc site start command

4f7105c

To start Jest doc, we need to run `fetchSupporters` first otherwise it's not possible to start doc server

ahnpnl force-pushed the feat/config-utils branch from 565fc14 to 4f7105c Compare October 9, 2025 18:10

ahnpnl changed the title ~~feat(config): add defineConfig and mergeConfig functions~~ feat(jest-config): add defineConfig and mergeConfig functions Oct 9, 2025

SimenB approved these changes Oct 10, 2025

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SimenB merged commit 96c53d3 into jestjs:main Oct 10, 2025
74 checks passed

ahnpnl deleted the feat/config-utils branch October 11, 2025 10:09

github-actions bot locked as resolved and limited conversation to collaborators Nov 11, 2025

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feat(jest-config): add `defineConfig` and `mergeConfig` functions#15844

feat(jest-config): add `defineConfig` and `mergeConfig` functions#15844
SimenB merged 2 commits intojestjs:mainfrom
ahnpnl:feat/config-utils

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