Babel preset: Make Platform inlining opt-in via inlinePlatform (default on via @react-native/metro-babel-transformer) (#57973) - #57973
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Babel preset: Make Platform inlining opt-in via inlinePlatform (default on via @react-native/metro-babel-transformer) (#57973)#57973robhogan wants to merge 1 commit into
@react-native/metro-babel-transformer) (#57973)#57973robhogan wants to merge 1 commit into
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…lt on via `@react-native/metro-babel-transformer`) (#57973) Summary: `react-native/babel-preset` inlines `Platform.OS` and `Platform.select(...)` whenever it is handed a `platform` (since yesterday - #57848 ), but this is over-zealous - `platform` is a pre-existing transform option whose intent is to set the transform target. In some cases (eg, to allow `Platform` mocking from tests), we don't want `Platform` inlining, even though `platform` may already be passed for other reasons. Gate the inlining behind a separate `inlinePlatform` opt-in, resolved as `options.inlinePlatform ?? babel.caller(...) ?? false`, mirroring how `platform` and `unstable_transformProfile` are already resolved. Metro already models this as a distinct transform option, so both Babel transformers pass it straight through. The caller channel covers the case where the preset is named in a `babel.config.js` and so receives no preset options at all. Bundling is unaffected: Metro sets `inlinePlatform` on every transform, so `Platform` continues to be inlined through `react-native/metro-babel-transformer`. Changelog: [General][Changed] - `Platform.OS` and `Platform.select(...)` inlining in `react-native/babel-preset` now requires the `inlinePlatform` option in addition to `platform` Reviewed By: GijsWeterings Differential Revision: D116281656
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…lt on via `@react-native/metro-babel-transformer`) Summary: X-link: react/react-native#57973 `react-native/babel-preset` inlines `Platform.OS` and `Platform.select(...)` whenever it is handed a `platform` (since yesterday - react/react-native#57848 ), but this is over-zealous - `platform` is a pre-existing transform option whose intent is to set the transform target. In some cases (eg, to allow `Platform` mocking from tests), we don't want `Platform` inlining, even though `platform` may already be passed for other reasons. Gate the inlining behind a separate `inlinePlatform` opt-in, resolved as `options.inlinePlatform ?? babel.caller(...) ?? false`, mirroring how `platform` and `unstable_transformProfile` are already resolved. Metro already models this as a distinct transform option, so both Babel transformers pass it straight through. The caller channel covers the case where the preset is named in a `babel.config.js` and so receives no preset options at all. Bundling is unaffected: Metro sets `inlinePlatform` on every transform, so `Platform` continues to be inlined through `react-native/metro-babel-transformer`. Changelog: [General][Changed] - `Platform.OS` and `Platform.select(...)` inlining in `react-native/babel-preset` now requires the `inlinePlatform` option in addition to `platform` Reviewed By: GijsWeterings Differential Revision: D116281656 fbshipit-source-id: 0230cd74f38661862396391da62cf81b34773b85
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Summary:
react-native/babel-presetinlinesPlatform.OSandPlatform.select(...)whenever it is handed aplatform(since yesterday - #57848 ), but this is over-zealous -platformis a pre-existing transform option whose intent is to set the transform target. In some cases (eg, to allowPlatformmocking from tests), we don't wantPlatforminlining, even thoughplatformmay already be passed for other reasons.Gate the inlining behind a separate
inlinePlatformopt-in, resolved asoptions.inlinePlatform ?? babel.caller(...) ?? false, mirroring howplatformandunstable_transformProfileare already resolved. Metro already models this as a distinct transform option, so both Babel transformers pass it straight through. The caller channel covers the case where the preset is named in ababel.config.jsand so receives no preset options at all.Bundling is unaffected: Metro sets
inlinePlatformon every transform, soPlatformcontinues to be inlined throughreact-native/metro-babel-transformer.Changelog:
[General][Changed] -
Platform.OSandPlatform.select(...)inlining inreact-native/babel-presetnow requires theinlinePlatformoption in addition toplatformReviewed By: GijsWeterings
Differential Revision: D116281656