Add more runtime guards

lib/conversion.ts

@@ -35,14 +35,23 @@ function elect<T>(candidates: Partial<Record<CandidateKey, T>>, locale: string):
 /**
  * A wrapper around `elect()` to ensure no non-string results are returned.
  */
-function electString(candidates: Candidates, locale: string): string {
+function safeElect(candidates: Candidates, locale: string): string {
+  // Guards to ensure types at runtime
   if (!isPlainObject(candidates)) {
-    throw new TypeError('[HanAssist] Invalid parameter. Needs to be an object.');
+    throw new TypeError('[HanAssist] Invalid parameter. Must be an object.');
+  }
+  if (typeof locale !== 'string') {
+    mw.log.warn('[HanAssist] locale parameter must be a string. Please check your code.');
+    locale = safelyToString(locale);
   }
 
   const result = elect(candidates, locale);
-  if (result === null) {
+
+  if (typeof result !== 'string') {
     mw.log.warn('[HanAssist] Non-string conversion result detected. Please check your code.');
+  }
+
+  if (result === null) {
     return '';
   }
 
@@ -56,7 +65,7 @@ function electString(candidates: Candidates, locale: string): string {
  * @returns selected value
  */
 function conv(candidates: Candidates): string {
-  return electString(candidates, mw.config.get('wgUserLanguage'));
+  return safeElect(candidates, mw.config.get('wgUserLanguage'));
 }
 
 /**
@@ -65,7 +74,7 @@ function conv(candidates: Candidates): string {
  * @returns selected value
  */
 function convByVar(candidates: Candidates): string {
-  return electString(candidates, mw.config.get('wgUserVariant') ?? mw.user.options.get('variant'));
+  return safeElect(candidates, mw.config.get('wgUserVariant') ?? mw.user.options.get('variant'));
 }
 
 /**
@@ -79,15 +88,15 @@ function batchConv(
   locale = mw.config.get('wgUserLanguage')
 ): Record<string, string> {
   if (!isPlainObject(candidatesDict)) {
-    throw new TypeError('[HanAssist] Invalid parameter. Needs to be an object.');
+    throw new TypeError('[HanAssist] Invalid parameter. Must be an object.');
   }
 
   const result: Record<string, string> = {};
 
   for (const key in candidatesDict) {
     const candidates = candidatesDict[key];
     const electionResult = isPlainObject(candidates)
-      ? electString(candidates, locale)
+      ? safeElect(candidates, locale)
       : safelyToString(candidates);
     result[key] = electionResult;
   }

lib/env.d.ts

@@ -1 +1 @@
-const __SHIM_UXS__: boolean;
+const COMPAT: boolean;

lib/index.ts

@@ -1,4 +1,4 @@
-if (__SHIM_UXS__) {
+if (COMPAT) {
   // Compatibility: redirect wgULS, wgUVS and wgUXS calls to HanAssist implementation
   import('./shims');
 }

lib/utils.ts

@@ -1,6 +1,5 @@
 /**
  * Safely convert an object to string.
- * @private
  * @param val value to convert
  * @return string
  */

package.json

@@ -13,7 +13,7 @@
   "scripts": {
     "preinstall": "npx only-allow pnpm",
     "build": "rollup -c",
-    "build:compat": "SHIM_UXS=1 rollup -c",
+    "build:compat": "COMPAT=1 rollup -c",
     "lint": "eslint .",
     "type-check": "tsc --noEmit",
     "test": "jest",

rollup.config.js

@@ -6,7 +6,7 @@ import { readFileSync } from 'fs';
 import mwGadget from 'rollup-plugin-mediawiki-gadget';
 import replace from '@rollup/plugin-replace';
 
-const shimUXS = process.env.SHIM_UXS !== undefined;
+const compat = process.env.COMPAT !== undefined;
 
 export default defineConfig({
   input: 'lib/index.ts',
@@ -22,7 +22,7 @@ export default defineConfig({
     typescript(),
     replace({
       preventAssignment: true,
-      __SHIM_UXS__: JSON.stringify(shimUXS),
+      COMPAT: JSON.stringify(compat),
     }),
     mwGadget({
       gadgetDef: './gadget-definition.txt',