Support a lazy raw color fallback for PlatformColor (#57701) - #57701
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Summary: An implementation for the RFC in react-native-community/discussions-and-proposals#1008 `PlatformColor` previously had no way to specify what color to use when none of the supplied native color tokens resolve on the device. On a miss the behavior was inconsistent across platforms and architectures (transparent, nil, or a thrown error), giving apps no control over the rendered result. This adds an optional trailing `{fallback: '<raw color string>'}` argument to `PlatformColor(...)` and updates the JS entry points to emit it. The fallback is carried lazily to native as a raw, unprocessed string and is only parsed when every provided token fails to resolve (the native side of that behavior landed earlier in this stack). When at least one token resolves the fallback is ignored, so existing call sites are completely unaffected and omitting the argument preserves today's exact behavior. Example: PlatformColor('someSystemToken', {fallback: '#FF0000'}) Each platform entry point (`PlatformColorValueTypes.{android,ios,macos,windows}.js`, plus the vendored macOS/Windows copies) collects the leading string tokens and, when a trailing `{fallback}` object is present, attaches its raw string to the native color object. Non-string arguments in a non-trailing position are filtered out consistently rather than being forwarded to native. The Flow (`.js.flow`), TypeScript (`.d.ts`), and generated (`ReactNativeApi.d.ts`) declarations widen the signature to `Array<string | {fallback: string}>`, which is backward compatible. Changelog: [General][Added] - Support a lazy raw color fallback for PlatformColor when native tokens fail to resolve Differential Revision: D113329139
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Summary: An implementation for the RFC in react-native-community/discussions-and-proposals#1008 `PlatformColor` previously had no way to specify what color to use when none of the supplied native color tokens resolve on the device. On a miss the behavior was inconsistent across platforms and architectures (transparent, nil, or a thrown error), giving apps no control over the rendered result. This adds an optional trailing `{fallback: '<raw color string>'}` argument to `PlatformColor(...)` and updates the JS entry points to emit it. The fallback is carried lazily to native as a raw, unprocessed string and is only parsed when every provided token fails to resolve (the native side of that behavior landed earlier in this stack). When at least one token resolves the fallback is ignored, so existing call sites are completely unaffected and omitting the argument preserves today's exact behavior. Example: PlatformColor('someSystemToken', {fallback: '#FF0000'}) Each platform entry point (`PlatformColorValueTypes.{android,ios,macos,windows}.js`, plus the vendored macOS/Windows copies) collects the leading string tokens and, when a trailing `{fallback}` object is present, attaches its raw string to the native color object. Non-string arguments in a non-trailing position are filtered out consistently rather than being forwarded to native. The Flow (`.js.flow`), TypeScript (`.d.ts`), and generated (`ReactNativeApi.d.ts`) declarations widen the signature to `Array<string | {fallback: string}>`, which is backward compatible. Changelog: [General][Added] - Support a lazy raw color fallback for PlatformColor when native tokens fail to resolve Differential Revision: D113329139
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Summary: An implementation for the RFC in react-native-community/discussions-and-proposals#1008 `PlatformColor` previously had no way to specify what color to use when none of the supplied native color tokens resolve on the device. On a miss the behavior was inconsistent across platforms and architectures (transparent, nil, or a thrown error), giving apps no control over the rendered result. This adds an optional trailing `{fallback: '<raw color string>'}` argument to `PlatformColor(...)` and updates the JS entry points to emit it. The fallback is carried lazily to native as a raw, unprocessed string and is only parsed when every provided token fails to resolve (the native side of that behavior landed earlier in this stack). When at least one token resolves the fallback is ignored, so existing call sites are completely unaffected and omitting the argument preserves today's exact behavior. Example: PlatformColor('someSystemToken', {fallback: '#FF0000'}) Each platform entry point (`PlatformColorValueTypes.{android,ios,macos,windows}.js`, plus the vendored macOS/Windows copies) collects the leading string tokens and, when a trailing `{fallback}` object is present, attaches its raw string to the native color object. Non-string arguments in a non-trailing position are filtered out consistently rather than being forwarded to native. The Flow (`.js.flow`), TypeScript (`.d.ts`), and generated (`ReactNativeApi.d.ts`) declarations widen the signature to `Array<string | {fallback: string}>`, which is backward compatible. Changelog: [General][Added] - Support a lazy raw color fallback for PlatformColor when native tokens fail to resolve Differential Revision: D113329139
Summary: An implementation for the RFC in react-native-community/discussions-and-proposals#1008 `PlatformColor` previously had no way to specify what color to use when none of the supplied native color tokens resolve on the device. On a miss the behavior was inconsistent across platforms and architectures (transparent, nil, or a thrown error), giving apps no control over the rendered result. This adds an optional trailing `{fallback: '<raw color string>'}` argument to `PlatformColor(...)` and updates the JS entry points to emit it. The fallback is carried lazily to native as a raw, unprocessed string and is only parsed when every provided token fails to resolve (the native side of that behavior landed earlier in this stack). When at least one token resolves the fallback is ignored, so existing call sites are completely unaffected and omitting the argument preserves today's exact behavior. Example: PlatformColor('someSystemToken', {fallback: '#FF0000'}) Each platform entry point (`PlatformColorValueTypes.{android,ios,macos,windows}.js`, plus the vendored macOS/Windows copies) collects the leading string tokens and, when a trailing `{fallback}` object is present, attaches its raw string to the native color object. Non-string arguments in a non-trailing position are filtered out consistently rather than being forwarded to native. The Flow (`.js.flow`), TypeScript (`.d.ts`), and generated (`ReactNativeApi.d.ts`) declarations widen the signature to `Array<string | {fallback: string}>`, which is backward compatible. Changelog: [General][Added] - Support a lazy raw color fallback for PlatformColor when native tokens fail to resolve Differential Revision: D113329139
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Summary:
An implementation for the RFC in react-native-community/discussions-and-proposals#1008
PlatformColorpreviously had no way to specify what color to use when none of the supplied native color tokens resolve on the device. On a miss the behavior was inconsistent across platforms and architectures (transparent, nil, or a thrown error), giving apps no control over the rendered result.This adds an optional trailing
{fallback: '<raw color string>'}argument toPlatformColor(...)and updates the JS entry points to emit it. The fallback is carried lazily to native as a raw, unprocessed string and is only parsed when every provided token fails to resolve (the native side of that behavior landed earlier in this stack). When at least one token resolves the fallback is ignored, so existing call sites are completely unaffected and omitting the argument preserves today's exact behavior.Example:
PlatformColor('someSystemToken', {fallback: '#FF0000'})
Each platform entry point (
PlatformColorValueTypes.{android,ios,macos,windows}.js, plus the vendored macOS/Windows copies) collects the leading string tokens and, when a trailing{fallback}object is present, attaches its raw string to the native color object. Non-string arguments in a non-trailing position are filtered out consistently rather than being forwarded to native. The Flow (.js.flow), TypeScript (.d.ts), and generated (ReactNativeApi.d.ts) declarations widen the signature toArray<string | {fallback: string}>, which is backward compatible.Changelog:
[General][Added] - Support a lazy raw color fallback for PlatformColor when native tokens fail to resolve
Differential Revision: D113329139