Native code highlighting

Optional syntax highlighting for @apollohg/react-native-rich-text-editor. Requires Expo native modules and a native app rebuild after installation.

npm install @apollohg/react-native-rich-text-editor-code-highlighting

import { RichTextEditor } from '@apollohg/react-native-rich-text-editor';
import { createCodeHighlightingAddon } from '@apollohg/react-native-rich-text-editor-code-highlighting';

const highlighting = createCodeHighlightingAddon({ theme: 'base16-ocean.dark' });

<RichTextEditor documentHandle={documentHandle} addons={[highlighting]} />;

RichTextViewer accepts the same addon. Set the code block's language attribute to select its grammar. Supported language values are javascript/js, typescript/ts, tsx, jsx, swift, kotlin/kt, rust/rs, python/py, json, html, css, and bash/shell/sh. JSX uses the TypeScript React grammar. Missing, plain, and unsupported language values render ordinary code without guessing.

codeHighlightingThemes lists the seven supported theme names. The selected theme contributes token foregrounds and bold/italic/underline traits. The editor's codeBlock style controls panel geometry and background.

The package registers its native provider synchronously when imported. Factories only create immutable configuration. Omit the descriptor to disable work for a view; uninstall and rebuild to remove the engine and grammar assets from the app. The base editor does not install this package automatically.

The engine uses syntect 5.3.0 with its pure Rust regex backend and the two-face 0.5.1 compatible grammar pack. Prebuilt libraries are included for iOS device/simulator and Android arm64-v8a, armeabi-v7a, x86, and x86_64. Consumer installation does not invoke Cargo.

Blocks over 64 KiB, lines over 4 KiB, or blocks over 1,000 lines fall back to ordinary styling. A worker-local cache retains at most 64 blocks and 1 MiB of accounted source/range data. Regex backtracking has the upstream finite step limit; this is not a wall-clock timeout. No syntax state or color marks are written to the document.

The core and all extensions share the same release version. Installing only the core does not install this extension or its native engine and grammar assets.

Maintainers build from this repository with Rust 1.95.0, the seven mobile Rust targets, Xcode, Android NDK and cargo-ndk installed:

npm run build
npm run test:rust
npm run build:native
npm pack

Licenses and attribution

This package's own code is Apache-2.0. Syntect is MIT-licensed; its bundled grammars, themes, Rust dependencies, and native dependencies retain their own licenses. Full texts, copyright notices, and corresponding-source links are included in THIRD_PARTY_NOTICES.md and RUST-STANDARD-LIBRARY-NOTICES.html.

Include these notices alongside the core editor's notices in your distributed app's open-source acknowledgements or accompanying materials. Keep the MPL corresponding-source links and notices for the framework/native dependency versions your app actually resolves. Refresh these files when upgrading dependencies, syntax/theme assets, or the Rust toolchain.

Releases

Bump versions from the repository root with npm version; its version hook synchronizes every extension and the example lockfile. The Publish / Dry Run workflow builds and validates the core and highlighting artifacts, then publishes them together when a GitHub release is published. Pushes and pull requests affecting extensions run the same validation without publishing. Unchanged native sources reuse their own build cache; JavaScript and tarballs are always rebuilt. A retry skips package versions already published after a partial release.