From cd62e12069bbb7a70e9d9b980be68cb30956e450 Mon Sep 17 00:00:00 2001
From: Evgeny Alaev <alaev89@yandex-team.ru>
Date: Fri, 26 Jan 2024 14:38:47 +0300
Subject: [PATCH] fix: review fixes

---
 src/index.ts               | 22 ++++++++++++++--------
 src/replace-params.ts      |  2 +-
 src/translation-helpers.ts |  4 ++--
 tsconfig.json              |  3 ++-
 4 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/src/index.ts b/src/index.ts
index bb0f827..b38d141 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -132,7 +132,7 @@ export class I18N {
     has(keysetName: string, key: string, lang?: string) {
         const languageData = this.getLanguageData(lang);
 
-        return Boolean(languageData && languageData[keysetName] && languageData[keysetName][key]);
+        return Boolean(languageData && languageData[keysetName] && languageData[keysetName]?.[key]);
     }
 
     i18n(keysetName: string, key: string, params?: Params): string {
@@ -150,12 +150,12 @@ export class I18N {
             const message = mapErrorCodeToMessage({
                 code: details.code,
                 lang: this.lang,
-                fallbackLang: this.fallbackLang,
+                fallbackLang: this.fallbackLang === this.lang ? undefined : this.fallbackLang,
             });
             this.warn(message, details.keysetName, details.key);
         }
 
-        if (this.fallbackLang) {
+        if (text === undefined && this.fallbackLang && this.fallbackLang !== this.lang) {
             ({text, fallbackText, details} = this.getTranslationData({
                 keysetName,
                 key,
@@ -166,14 +166,14 @@ export class I18N {
             if (details && details.code !== ErrorCode.NoLanguageData) {
                 const message = mapErrorCodeToMessage({
                     code: details.code,
-                    lang: this.lang,
-                    fallbackLang: this.fallbackLang,
+                    lang: this.fallbackLang,
                 });
                 this.warn(message, details.keysetName, details.key);
             }
         }
 
-        if (!text && !fallbackText) {
+        const result = text ?? fallbackText;
+        if (result === undefined) {
             const message = mapErrorCodeToMessage({
                 code: details?.code,
                 lang: this.lang,
@@ -182,7 +182,7 @@ export class I18N {
             throw new Error(message);
         }
 
-        return (text || fallbackText) as string;
+        return result;
     }
 
     keyset<TKey extends string = string>(keysetName: string) {
@@ -265,7 +265,7 @@ export class I18N {
         const keyValue = keyset && keyset[key];
         const result: TranslationData = {};
 
-        if (typeof keyValue === 'undefined') {
+        if (keyValue === undefined) {
             return {
                 fallbackText: key,
                 details: {code: ErrorCode.MissingKey, keysetName, key},
@@ -291,6 +291,12 @@ export class I18N {
 
             const pluralizer = this.getLanguagePluralizer(lang);
             result.text = keyValue[pluralizer(count, PluralForm)] || keyValue[PluralForm.Many];
+            if (result.text === undefined) {
+                return {
+                    fallbackText: key,
+                    details: {code: ErrorCode.MissingKeyPlurals, keysetName, key},
+                };
+            }
 
             if (keyValue[PluralForm.None] === undefined) {
                 result.details = {
diff --git a/src/replace-params.ts b/src/replace-params.ts
index d2106e7..f8e79a9 100644
--- a/src/replace-params.ts
+++ b/src/replace-params.ts
@@ -14,7 +14,7 @@ export function replaceParams(keyValue: string, params: Params): string {
         lastIndex = PARAM_REGEXP.lastIndex;
 
         const [all, key] = match;
-        if (Object.prototype.hasOwnProperty.call(params, key)) {
+        if (key && Object.prototype.hasOwnProperty.call(params, key)) {
             result += params[key];
         } else {
             result += all;
diff --git a/src/translation-helpers.ts b/src/translation-helpers.ts
index 0d0a1e0..239ff33 100644
--- a/src/translation-helpers.ts
+++ b/src/translation-helpers.ts
@@ -42,7 +42,7 @@ export function mapErrorCodeToMessage(args: {lang?: string; fallbackLang?: strin
             break;
         }
         case ErrorCode.MissingKeyPlurals: {
-            message = 'Missing required plurals';
+            message = 'Missing required plurals.';
             break;
         }
         case ErrorCode.NoLanguageData: {
@@ -51,7 +51,7 @@ export function mapErrorCodeToMessage(args: {lang?: string; fallbackLang?: strin
     }
 
     if (fallbackLang) {
-        message += ` Trying to use default language "${fallbackLang}"...`;
+        message += ` Trying to use fallback language "${fallbackLang}"...`;
     }
 
     return message;
diff --git a/tsconfig.json b/tsconfig.json
index 1c06f60..940e607 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -5,7 +5,8 @@
     "module": "esnext",
     "baseUrl": ".",
     "importHelpers": true,
-    "declaration": true
+    "declaration": true,
+    "noUncheckedIndexedAccess": true
   },
   "include": ["src/*.ts"],
   "exclude": ["**/*.spec.ts"]