support only ESM module

rollup.config.js

@@ -1,26 +1,10 @@
-import commonjs from "@rollup/plugin-commonjs";
 import typescript from "@rollup/plugin-typescript";
 import terser from "@rollup/plugin-terser";
 
 const isProduction = process.env.NODE_ENV === "production";
 
 export default [
-  // browser-friendly UMD build
-  {
-    input: "src/main.ts",
-    output: {
-      name: "irem",
-      file: "dist/irem.umd.js",
-      format: "umd",
-    },
-    plugins: [
-      commonjs(), // so Rollup can convert `ms` to an ES module
-      typescript({ module: "esnext", tsconfig: "./tsconfig.json" }), // so Rollup can convert TypeScript to JavaScript
-      isProduction && terser(),
-    ],
-  },
-
-  // CommonJS (for Node) and ES module (for bundlers) build.
+  // ES module (for bundlers) build.
   // (We could have three entries in the configuration array
   // instead of two, but it's quicker to generate multiple
   // builds from a single configuration where possible, using
@@ -33,9 +17,6 @@ export default [
       typescript({ module: "esnext", tsconfig: "./tsconfig.json" }), // so Rollup can convert TypeScript to JavaScript
       isProduction && terser(),
     ],
-    output: [
-      { file: "dist/irem.cjs.js", format: "cjs" },
-      { file: "dist/irem.esm.js", format: "es" },
-    ],
+    output: [{ file: "dist/irem.esm.js", format: "es" }],
   },
 ];

src/main.ts

@@ -8,11 +8,9 @@ import {
 import { readFileSync } from "fs";
 import { isSupportedNonEnglishLanguage } from "./util";
 
-export async function getAllCountries(
-  language?: SupportedLanguage,
-): Promise<SimpleCountry[]> {
+export function getAllCountries(language?: SupportedLanguage): SimpleCountry[] {
   const t1 = new Date().getTime();
-  const data = await readJSON(language);
+  const data = readJSON(language);
   const t2 = new Date().getTime();
   console.log((t2 - t1) / 1000, " seconds passed ");
 
@@ -28,11 +26,11 @@ export async function getAllCountries(
   return countries;
 }
 
-export async function getAllRegionsOfCountry(
+export function getAllRegionsOfCountry(
   countryCode: CountryCode,
   language?: SupportedLanguage,
-): Promise<SimplePlace[]> {
-  const data = await readJSON(language);
+): SimplePlace[] {
+  const data = readJSON(language);
   const regions: SimplePlace[] = [];
   for (const regionNameInEnglish in data[countryCode][">"]) {
     regions.push({
@@ -43,27 +41,28 @@ export async function getAllRegionsOfCountry(
   return regions;
 }
 
-// export async function getAllCities(
-//   countryCode: CountryCode,
-//   language?: SupportedLanguage,
-// ): SimplePlace[] {
-//   const data = await readJSON(language);
+export function getAllCities(
+  countryCode: CountryCode,
+  regionNameInEnglish: string,
+  language?: SupportedLanguage,
+): SimplePlace[] {
+  const data = readJSON(language);
 
-//   const regions: SimplePlace[] = [];
-//   for (const regionNameInEnglish in data[countryCode][">"]) {
-//     regions.push({
-//       englishName: regionNameInEnglish,
-//       name: data[countryCode][">"][regionNameInEnglish].t,
-//     });
-//   }
-//   return regions;
-// }
+  const cities: SimplePlace[] = [];
+  for (const cityName in data[countryCode][">"][regionNameInEnglish][">"]) {
+    cities.push({
+      englishName: cityName,
+      name: data[countryCode][">"][regionNameInEnglish][">"][cityName].t,
+    });
+  }
+  return cities;
+}
 
-async function readJSON(
+function readJSON(
   language?: SupportedLanguage,
   nonEnglishDataPath: string = "./data/",
   englishDataPath: string = "./data/",
-): Promise<Record<CountryCode, CountryData>> {
+): Record<CountryCode, CountryData> {
   const fileToRead = isSupportedNonEnglishLanguage(language)
     ? `${nonEnglishDataPath}GPS-data-${language}.json`
     : `${englishDataPath}GPS-data.json`;

test/main.spec.ts

@@ -1,18 +1,22 @@
-import { getAllCountries, getAllRegionsOfCountry } from "../src/main";
+import {
+  getAllCities,
+  getAllCountries,
+  getAllRegionsOfCountry,
+} from "../src/main";
 import { describe, test, expect } from "vitest";
 import { supportedNonEnglishLanguages } from "../src/util";
 
 describe("allCountriesInEnglish", () => {
   test.each([...supportedNonEnglishLanguages, "en", "EN", "undefined"])(
     "should get all countries in Language %s",
-    async (language) => {
-      const allCountries = await getAllCountries(language);
+    (language) => {
+      const allCountries = getAllCountries(language);
       expect(allCountries).toHaveLength(242);
     },
   );
 
-  test("should get Turkey from all countries in Turkish", async () => {
-    const allCountriesInTurkish = await getAllCountries("tr");
+  test("should get Turkey from all countries in Turkish", () => {
+    const allCountriesInTurkish = getAllCountries("tr");
     const turkey = allCountriesInTurkish.find((x) => x.code == "TR");
     expect(turkey).toEqual({
       code: "TR",
@@ -23,13 +27,13 @@ describe("allCountriesInEnglish", () => {
 });
 
 describe("getAllRegionsOfCountry", () => {
-  test("should get 81 regions (cities) in Turkey", async () => {
-    const allRegionsInTurkey = await getAllRegionsOfCountry("TR", "tr");
+  test("should get 81 regions (cities) in Turkey", () => {
+    const allRegionsInTurkey = getAllRegionsOfCountry("TR", "tr");
     expect(allRegionsInTurkey.length).toBe(81);
   });
 
-  test("should get Kocaeli and İstanbul cities in Turkey", async () => {
-    const allRegionsInTurkey = await getAllRegionsOfCountry("TR", "tr");
+  test("should get Kocaeli and İstanbul cities in Turkey", () => {
+    const allRegionsInTurkey = getAllRegionsOfCountry("TR", "tr");
 
     const istanbul = allRegionsInTurkey.find(
       (x) => x.englishName === "İstanbul",
@@ -39,3 +43,11 @@ describe("getAllRegionsOfCountry", () => {
     expect(kocaeli).toEqual({ englishName: "Kocaeli", name: "" });
   });
 });
+
+describe("getAllCities", () => {
+  test("should get cities (districts) in Ankara in Turkey", () => {
+    const allPlacesInAnkara = getAllCities("TR", "Ankara", "tr");
+    console.log("allPlacesInAnkara: ", allPlacesInAnkara);
+    expect(allPlacesInAnkara.length).toBe(26);
+  });
+});