Gate jsxDEV source/self with `developmentSourceSelf` option by rootvector2 · Pull Request #17845 · babel/babel

rootvector2 · 2026-03-01T15:47:35Z

Q	A
Fixed Issues?	Fixes #17571
Patch: Bug Fix?
Major: Breaking Change?	👍
Minor: New Feature?	👍
Tests Added + Pass?	Yes
Documentation PR Link
Any Dependency Changes?
License	MIT

React 19.2 removed the source and self parameters from jsxDEV. Babel still unconditionally generates them in development mode which causes unnecessary overhead.

This PR adds a developmentSourceSelf option to @babel/plugin-transform-react-jsx and @babel/preset-react. When set to true the plugin generates __source and __self as before. The default is false in Babel 8 so the output aligns with the current React runtime.

Users who still need these arguments (e.g. older React versions or custom runtimes) can opt back in:

{
  "presets": [
    ["@babel/preset-react", { "development": true, "developmentSourceSelf": true }]
  ]
}

babel-bot · 2026-03-01T15:50:00Z

Build successful! You can test your changes in the REPL here: https://babeljs.io/repl/build/61107

pkg-pr-new · 2026-03-01T15:57:31Z

Open in StackBlitz

commit: 8131f04

packages/babel-preset-react/src/normalize-options.ts

rootvector2 · 2026-03-02T14:53:44Z

HI @JLHwung
i have set the default value to false instead of undefined

JLHwung

Thank you, this PR looks good to me.

I marked this PR as a breaking change because we will not release new minor for Babel 7 and the new output may not work with old React versions.

Could you also prepare a docs update to the babel-website? Specifically, we will need a migration note mentioning this change in https://github.com/babel/website/blob/main/docs/v8-migration.md

JLHwung · 2026-03-02T16:09:31Z

The CI error is not related and has been fixed on main. I will rebase this branch to make the CI green.

rootvector2 · 2026-03-02T16:31:05Z

Thank you, this PR looks good to me.

I marked this PR as a breaking change because we will not release new minor for Babel 7 and the new output may not work with old React versions.

Could you also prepare a docs update to the babel-website? Specifically, we will need a migration note mentioning this change in https://github.com/babel/website/blob/main/docs/v8-migration.md

Done i have prepare a docs update to the babel-website...
babel/website#3185

nicolo-ribaudo

Thanks, this looks good to me and I agree with the new default.

I don't know if we'll have another Babel 7 minor release, but if we do, do you think we should backport this PR (with the default value flipped to true)?

rootvector2 · 2026-03-03T00:20:33Z

yeah I think backporting makes sense. with the default set to true there's no breaking change for babel 7 users, and it gives people on react 19.2+ a way to opt out early. also makes the babel 8 migration smoother since they can set the option explicitly before upgrading.

JLHwung · 2026-03-03T15:16:42Z

packages/babel-plugin-transform-react-jsx/src/create-plugin.ts

      pragma: PRAGMA_DEFAULT = DEFAULT.pragma,
      pragmaFrag: PRAGMA_FRAG_DEFAULT = DEFAULT.pragmaFrag,
+
+      developmentSourceSelf: DEVELOPMENT_SOURCE_SELF = false,


This option should be passed from createPlugin, rather than the returned plugin callback. The main plugin should not be aware of the developmentSourceSelf option.

pending option passing changes.

…tions Move developmentSourceSelf from the Options interface (user-facing plugin options) to the createPlugin factory parameter. This ensures the main plugin is not aware of the developmentSourceSelf option. The preset-react now imports createPlugin directly and passes developmentSourceSelf when creating the development plugin instance.

JLHwung

Thank you!

JLHwung · 2026-03-04T14:54:02Z

The CI error is related, could you run make tscheck and checkout the modified tsconfig.paths.json?

rootvector2 · 2026-03-04T21:27:03Z

@JLHwung Done

nicolo-ribaudo · 2026-03-07T22:58:02Z

Merging, thanks :)

It'd be great if you could also prepare a backport PR targeting the 7.x branch, but we will only actually merge it if/when we release a new Babel 7 minor (which, if it happens, will probably be in a few months)

Backport of babel#17845 to the 7.x branch, as requested by nicolo-ribaudo. Adds a `developmentSourceSelf` option to `@babel/preset-react` (and `sourceSelf` to the underlying JSX development plugin) that controls whether `__source` and `__self` attributes are injected in jsxDEV calls. React 19.2+ generates these from the callsite, making Babel injection unnecessary and sometimes harmful (duplicated props warnings). Default on 7.x: `true` (preserves backward compatibility). Default on 8.x: `false` (React 19.2+ is the common target). Users on React 19.2+ can opt out with: { "runtime": "automatic", "developmentSourceSelf": false }

rootvector2 · 2026-03-12T17:08:48Z

Merging, thanks :)

It'd be great if you could also prepare a backport PR targeting the 7.x branch, but we will only actually merge it if/when we release a new Babel 7 minor (which, if it happens, will probably be in a few months)

#17866
@nicolo-ribaudo Done

Added developmentSourceSelfoption to gatesource/self in jsxDEV

5845717

JLHwung reviewed Mar 2, 2026

View reviewed changes

packages/babel-preset-react/src/normalize-options.ts Show resolved Hide resolved

default value to false

17ec005

JLHwung added PR: Breaking Change 💥 A type of pull request used for our changelog categories for next major release PR: Needs Docs labels Mar 2, 2026

JLHwung previously approved these changes Mar 2, 2026

View reviewed changes

JLHwung force-pushed the jsx-dev-remove-source-self-default branch from 17ec005 to 9fa3a62 Compare March 2, 2026 16:09

rootvector2 mentioned this pull request Mar 2, 2026

Add migration note for developmentSourceSelf option babel/website#3185

Merged

nicolo-ribaudo approved these changes Mar 2, 2026

View reviewed changes

JLHwung reviewed Mar 3, 2026

View reviewed changes

rootvector2 force-pushed the jsx-dev-remove-source-self-default branch from 9fa3a62 to 6b7b62d Compare March 3, 2026 15:47

JLHwung approved these changes Mar 4, 2026

View reviewed changes

update tsconfig.paths.json for create-plugin export

8131f04

nicolo-ribaudo merged commit e259aae into babel:main Mar 7, 2026
55 checks passed

nicolo-ribaudo changed the title ~~Added developmentSourceSelfoption to gatesource/self in jsxDEV~~ Gate jsxDEV source/self with developmentSourceSelf option Mar 7, 2026

nicolo-ribaudo mentioned this pull request Mar 9, 2026

Add sourceSelf option to @babel/plugin-transform-react-jsx-development #17862

Merged

rootvector2 mentioned this pull request Mar 12, 2026

[7.x backport] Add developmentSourceSelf to JSX transform #17866

Open

Uh oh!

Conversation

rootvector2 commented Mar 1, 2026

Uh oh!

babel-bot commented Mar 1, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

pkg-pr-new bot commented Mar 1, 2026 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

Uh oh!

rootvector2 commented Mar 2, 2026

Uh oh!

JLHwung left a comment

Choose a reason for hiding this comment

Uh oh!

JLHwung commented Mar 2, 2026

Uh oh!

rootvector2 commented Mar 2, 2026

Uh oh!

nicolo-ribaudo left a comment

Choose a reason for hiding this comment

Uh oh!

rootvector2 commented Mar 3, 2026

Uh oh!

JLHwung Mar 3, 2026

Choose a reason for hiding this comment

Uh oh!

JLHwung left a comment

Choose a reason for hiding this comment

Uh oh!

JLHwung commented Mar 4, 2026

Uh oh!

rootvector2 commented Mar 4, 2026

Uh oh!

nicolo-ribaudo commented Mar 7, 2026

Uh oh!

Uh oh!

rootvector2 commented Mar 12, 2026

Uh oh!

Reviewers

Assignees

Labels

Projects

Milestone

Development

Uh oh!

4 participants

babel-bot commented Mar 1, 2026 •

edited

Loading

pkg-pr-new bot commented Mar 1, 2026 •

edited

Loading