Summary
React Review reports local Expo config plugins as unused-file when they are referenced from app.config.ts via Expo's documented string-path plugin syntax.
What happened
In an Expo SDK 56 app, app.config.ts uses local config plugins like this:
export default (): ExpoConfig => ({
plugins: [
"./plugins/android-secure-flag.plugin.ts",
"./plugins/android-faster-startup-no-bundle.ts",
"./plugins/android-day-night-theme.ts",
"./plugins/android-res-config.ts",
],
})React Review flagged each target plugin file:
plugins/android-day-night-theme.ts:0
Unused file — not reachable from any entry point
Rule: unused-file
plugins/android-faster-startup-no-bundle.ts:0
Unused file — not reachable from any entry point
Rule: unused-file
plugins/android-res-config.ts:0
Unused file — not reachable from any entry point
Rule: unused-file
plugins/android-secure-flag.plugin.ts:0
Unused file — not reachable from any entry point
Rule: unused-file
These files are not unused from Expo's perspective: Expo resolves and runs local config plugins listed by string path in the plugins array.
Why this seems like a false positive
Expo docs show local config plugins being added by path in app config:
plugins: [
["./plugins/withPlugin.ts"],
]
The app validates successfully:
npx expo config --json
npx expo config --type introspect --json
Native builds also pass:
cd android && ./gradlew :app:assembleDebug
bun ios -- --device generic --no-bundler --no-install
Expected behavior
unused-file should treat local Expo config plugin string paths in app.config.ts / app.config.js / app.json as reachability edges, so the plugin implementation files are not reported as unused.
Notes
I searched existing issues for combinations of unused-file, Expo, config plugin, and app.config.ts and did not find an existing report.
Interestingly, running the local CLI did not reproduce the exact unused-file warnings for me:
npx react-doctor@latest --verbose --diff --offline --fail-on none
This returned only unrelated warnings in changed React UI files, while React Review in the PR reported the four unused-file warnings above. So this may be specific to the React Review environment or to the dead-code/reachability pass used there.
Summary
React Review reports local Expo config plugins as
unused-filewhen they are referenced fromapp.config.tsvia Expo's documented string-path plugin syntax.What happened
In an Expo SDK 56 app,
app.config.tsuses local config plugins like this:React Review flagged each target plugin file:
These files are not unused from Expo's perspective: Expo resolves and runs local config plugins listed by string path in the
pluginsarray.Why this seems like a false positive
Expo docs show local config plugins being added by path in app config:
The app validates successfully:
Native builds also pass:
Expected behavior
unused-fileshould treat local Expo config plugin string paths inapp.config.ts/app.config.js/app.jsonas reachability edges, so the plugin implementation files are not reported as unused.Notes
I searched existing issues for combinations of
unused-file,Expo,config plugin, andapp.config.tsand did not find an existing report.Interestingly, running the local CLI did not reproduce the exact
unused-filewarnings for me:This returned only unrelated warnings in changed React UI files, while React Review in the PR reported the four
unused-filewarnings above. So this may be specific to the React Review environment or to the dead-code/reachability pass used there.