Support non-enumerable 'cause' on errors

Declare a type-only readonly `cause?: unknown` on HookError and SensitiveInfoError so TS configs that predate ES2022 type-check. Update HookError to accept an options object, install the `cause` property via Object.defineProperty when `'cause' in options` (so passing { cause: undefined } still creates a non-enumerable own property), and wire up operation/hint from the options. Add tests for HookError and SensitiveInfoError that assert a non-enumerable own `cause` is defined when explicitly passed as undefined. Also remove react-native-specific exports from package.json.

Author: mCodex

package.json

@@ -10,7 +10,6 @@
 	"sideEffects": false,
 	"exports": {
 		".": {
-			"react-native": "./src/index.ts",
 			"import": {
 				"types": "./lib/typescript/module/src/index.d.ts",
 				"default": "./lib/module/index.js"
@@ -22,7 +21,6 @@
 			"default": "./lib/module/index.js"
 		},
 		"./hooks": {
-			"react-native": "./src/hooks/index.ts",
 			"import": {
 				"types": "./lib/typescript/module/src/hooks/index.d.ts",
 				"default": "./lib/module/hooks/index.js"
@@ -34,7 +32,6 @@
 			"default": "./lib/module/hooks/index.js"
 		},
 		"./errors": {
-			"react-native": "./src/errors.ts",
 			"import": {
 				"types": "./lib/typescript/module/src/errors.d.ts",
 				"default": "./lib/module/errors.js"

src/__tests__/errors.test.ts

@@ -88,6 +88,18 @@ describe('errors', () => {
 				expect(Object.hasOwn(err, 'cause')).toBe(false)
 			})
 
+			it('defines a non-enumerable own cause when explicitly passed as undefined', () => {
+				const err = new SensitiveInfoError(ErrorCode.NotFound, 'wrapped', {
+					cause: undefined,
+				})
+				const descriptor = Object.getOwnPropertyDescriptor(err, 'cause')
+				expect(Object.hasOwn(err, 'cause')).toBe(true)
+				expect(err.cause).toBeUndefined()
+				expect(descriptor).toBeDefined()
+				expect(descriptor?.enumerable).toBe(false)
+				expect(Object.keys(err)).not.toContain('cause')
+			})
+
 			it('propagates cause through subclasses (NotFoundError)', () => {
 				const cause = new Error('native miss')
 				const err = new NotFoundError('missing', { cause })

src/__tests__/hooks.types.test.ts

@@ -35,6 +35,16 @@ describe('hooks/types', () => {
 		expect(Object.hasOwn(error, 'cause')).toBe(false)
 	})
 
+	it('defines a non-enumerable own cause when explicitly passed as undefined', () => {
+		const error = new HookError('Wrapper message', { cause: undefined })
+		const descriptor = Object.getOwnPropertyDescriptor(error, 'cause')
+		expect(Object.hasOwn(error, 'cause')).toBe(true)
+		expect(error.cause).toBeUndefined()
+		expect(descriptor).toBeDefined()
+		expect(descriptor?.enumerable).toBe(false)
+		expect(Object.keys(error)).not.toContain('cause')
+	})
+
 	it('creates the initial async state', () => {
 		const state = createInitialAsyncState<string>()
 		expect(state).toEqual({

src/errors.ts

@@ -62,6 +62,16 @@ export class SensitiveInfoError extends Error {
 	/** Stable discriminant identifying the failure mode. */
 	readonly code: ErrorCodeValue
 
+	/**
+	 * The underlying cause forwarded to {@link Error.cause}.
+	 *
+	 * Declared as a type-only member so the property type-checks under `tsconfig`
+	 * `lib` targets that predate ES2022 (where {@link Error} did not yet expose
+	 * `cause`). At runtime the value is installed by the constructor via
+	 * {@link Object.defineProperty} so it stays non-enumerable.
+	 */
+	declare readonly cause?: unknown
+
 	/**
 	 * @param code    - Stable {@link ErrorCodeValue} for the failure.
 	 * @param message - Human-readable description.

src/hooks/types.ts

@@ -30,25 +30,36 @@ export class HookError extends Error {
 	/** UI-facing remediation hint (e.g. `'Ask the user to retry biometrics.'`). */
 	readonly hint?: string | undefined
 
+	/**
+	 * The underlying cause forwarded to {@link Error.cause}.
+	 *
+	 * Declared as a type-only member so the property type-checks under `tsconfig`
+	 * `lib` targets that predate ES2022 (where {@link Error} did not yet expose
+	 * `cause`). At runtime the value is installed by the constructor via
+	 * {@link Object.defineProperty} so it stays non-enumerable.
+	 */
+	declare readonly cause?: unknown
+
 	/**
 	 * @param message - Human-readable description of the failure.
 	 * @param options - Additional metadata; see {@link HookErrorOptions}.
 	 */
-	constructor(
-		message: string,
-		{ cause, operation, hint }: HookErrorOptions = {}
-	) {
+	constructor(message: string, options: HookErrorOptions = {}) {
 		super(message)
 		this.name = 'HookError'
-		this.operation = operation
-		this.hint = hint
+		this.operation = options.operation
+		this.hint = options.hint
 		// Define `cause` manually instead of passing it to `super()` so this
 		// compiles cleanly under TS configs whose `lib` predates ES2022 (where
 		// the second `Error` constructor argument was introduced), while keeping
 		// the property non-enumerable to match the native ES2022 `Error` constructor.
-		if (cause !== undefined) {
+		//
+		// We deliberately use `'cause' in options` (rather than a value check)
+		// so that `new HookError(msg, { cause: undefined })` still installs the
+		// property — matching native `new Error(msg, { cause: undefined })`.
+		if ('cause' in options) {
 			Object.defineProperty(this, 'cause', {
-				value: cause,
+				value: options.cause,
 				writable: true,
 				configurable: true,
 				enumerable: false,