Merge pull request #14 from matrix-org/t3chguy/localazy-lint

package.json

@@ -17,7 +17,8 @@
     "bin": {
         "matrix-gen-i18n": "scripts/gen-i18n.js",
         "matrix-compare-i18n-files": "scripts/compare-file.js",
-        "matrix-i18n-rekey": "scripts/rekey.js"
+        "matrix-i18n-rekey": "scripts/rekey.js",
+        "matrix-i18n-lint": "scripts/lint.js"
     },
     "scripts": {
         "build:ts": "tsc",

scripts/common.ts

@@ -16,7 +16,7 @@ limitations under the License.
 
 import fs from "fs";
 import { isBinaryExpression, isStringLiteral, isTemplateLiteral, Node } from "@babel/types";
-import type { Translation, Translations } from "../src";
+import type { PluralisedTranslation, Translation, Translations } from "../src";
 
 export const NESTING_KEY = process.env["NESTING_KEY"] || "|";
 export const INPUT_FILE = process.env["INPUT_FILE"] || 'src/i18n/strings/en_EN.json';
@@ -57,3 +57,7 @@ export function getTKey(arg: Node): string | null {
     }
     return null;
 }
+
+export function isPluralisedTranslation(translation: Translations[string]): translation is PluralisedTranslation {
+    return typeof translation === "object" && "other" in translation;
+}

scripts/lint-i18n.ts

@@ -0,0 +1,50 @@
+/*
+Copyright 2023 The Matrix.org Foundation C.I.C.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+/**
+ * Applies the following lint rules to the src/i18n/strings/en_EN.json file:
+ *  + ensures the translation key is not equal to its value
+ *  + ensures the translation key contains only alphanumerics and underscores
+ *
+ * Usage: node scripts/lint-i18n.js
+ */
+
+import { getTranslations, isPluralisedTranslation } from "./common";
+
+const input = getTranslations();
+
+const filtered = Object.keys(input).filter(key => {
+    const value = input[key];
+
+    // Check for invalid characters in the translation key
+    if (!!key.replace(/[a-z0-9_]+/g, "")) {
+        console.log(`"${key}": key contains invalid characters`);
+        return true;
+    }
+
+    // Check that the translated string does not match the key.
+    if (key === input[key] || (isPluralisedTranslation(value) && (key === value.other || key === value.one))) {
+        console.log(`"${key}": key matches value`);
+        return true;
+    }
+
+    return false;
+});
+
+if (filtered.length > 0) {
+    console.log(`${filtered.length} invalid translation keys`);
+    process.exit(1);
+}

src/types.ts

@@ -61,11 +61,13 @@ type Join<K, P, S extends string = "."> = K extends string | number
  */
 export type TranslationKey<T extends Translations> = Leaves<T, typeof KEY_SEPARATOR, string | { other: string }, 4>;
 
-export type Translation = string | {
+export type PluralisedTranslation = {
     one?: string;
     other: string;
 };
 
+export type Translation = string | PluralisedTranslation;
+
 export interface Translations {
     [key: string]: Translation | Translations;
 }