feat: enable reading fonts registered via addCustomFont#55711
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vonovak wants to merge 1 commit intofacebook:mainfrom
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feat: enable reading fonts registered via addCustomFont#55711vonovak wants to merge 1 commit intofacebook:mainfrom
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Summary: `ReactFontManager` has a write-only API for custom fonts — you can register fonts but there's no way to query what's been registered. This asymmetry means a library that needs to know about font availability needs to use reflection on the private `customTypefaceCache` map, or maintain a custom registry that can easily go out of sync. This becomes a problem when multiple libraries need to cooperate around fonts. Today when a library registers a font, there's no clean way for another library to discover what the first one registered. This adds a `customFontFamilies` property that returns the set of font family names currently in the custom typeface cache. Only `customTypefaceCache` is exposed in this PR because it contains fonts explicitly registered by library code via `addCustomFont()`, whereas `fontCache` is lazily populated as a side effect of `getTypeface()` calls and its contents depend on what has been requested so far rather than what is available. Asset-based fonts (in `assets/fonts/`) already have a discoverable source of truth - the filesystem. ## Changelog: [ANDROID] [ADDED] - `ReactFontManager.customFontFamilies` property to query registered custom font family names Pull Request resolved: facebook#55711 Test Plan: - tested ok by adding ```kt val customFonts = ReactFontManager.getInstance().customFontFamilies Log.d("RNTesterApplication", "customFontFamilies: $customFonts") ``` prints: `customFontFamilies: [Rubik, FiraCode]` [here](https://github.com/facebook/react-native/blob/9353eb55b877e6e51c35c6041eebd72971c6b9a5/packages/rn-tester/android/app/src/main/java/com/facebook/react/uiapp/RNTesterApplication.kt#L123) Reviewed By: cortinico Differential Revision: D94665574 Pulled By: javache fbshipit-source-id: 07d802ac98f4a738858038a2af6ce8d85c28b5ce
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Summary:
ReactFontManagerhas a write-only API for custom fonts — you can register fonts but there's no way to query what's been registered. This asymmetry means a library that needs to know about font availability needs to use reflection on the privatecustomTypefaceCachemap, or maintain a custom registry that can easily go out of sync.This becomes a problem when multiple libraries need to cooperate around fonts. Today when a library registers a font, there's no clean way for another library to discover what the first one registered.
This adds a
customFontFamiliesproperty that returns the set of font family names currently in the custom typeface cache.Only
customTypefaceCacheis exposed in this PR because it contains fonts explicitly registered by library code viaaddCustomFont(), whereasfontCacheis lazily populated as a side effect ofgetTypeface()calls and its contents depend on what has been requested so far rather than what is available.Asset-based fonts (in
assets/fonts/) already have a discoverable source of truth - the filesystem.Changelog:
[ANDROID] [ADDED] -
ReactFontManager.customFontFamiliesproperty to query registered custom font family namesTest Plan:
prints:
customFontFamilies: [Rubik, FiraCode]here