fix(detection.js, createstrapi.js, packagedetection.js,yarnpackagehelper.js): bugfix for yarn pm

bugfix to give use the option to choose package manager of their choice if yarn npm both exists and
if yarn is provided in the quickstart option and yarn not installed install it for them.

Author: Sudeep Patel

utils/createStrapi.js

@@ -38,6 +38,7 @@ const createStrapiProject = async () => {
 			}
 		]);
 
+		/* eslint-disable */
 		async function checkPathAccessibility(targetPath) {
 			if (!path.isAbsolute(targetPath)) {
 				console.error(`${chalk.bold.red(

utils/detection.js

@@ -2,6 +2,9 @@ const path = require(`path`);
 const { spinner, chalk, constants, access } = require(`./utils`);
 const { setConfig, config } = require(`./config`);
 const fetch = require(`node-fetch`);
+const { checkInstalledPackages } = require(`./packageDetection`);
+const prompts = require(`prompts`);
+const { checkForYarnPackage } = require(`./yarnPackageHelper`);
 const { readFile } = require(`fs`).promises;
 
 const detectDownloadsAndStars = async () => {
@@ -60,6 +63,7 @@ const detectProjectType = async () => {
 
 const detectPackageManager = async () => {
 	spinner.start(` 💻 Detecting package manager... `);
+	spinner.stop();
 	try {
 		if (config.quickStart) {
 			spinner.stopAndPersist({
@@ -70,23 +74,72 @@ const detectPackageManager = async () => {
 						: `${chalk.bold.greenBright(`NPM`)}`
 				} set by cli arguments \n`
 			});
+			await checkForYarnPackage();
 			return;
 		}
-		await access(`yarn.lock`, constants.R_OK);
-		config.packageManager = `yarn`;
 	} catch (error) {
 		config.packageManager = `npm`;
-	}
-	if (!config.quickStart) {
 		spinner.stopAndPersist({
 			symbol: `📦`,
-			text: ` ${chalk.bold.yellow(
+			text: ` Exception Occured! falling back to ${chalk.bold.blueBright(
 				config.packageManager.toUpperCase()
-			)} detected \n`
+			)} \n`
 		});
 	}
-};
 
+	if (!config.quickStart) {
+		const installedPackages = await checkInstalledPackages();
+		if (installedPackages.length === 2) {
+			spinner.stopAndPersist({
+				symbol: `📂`,
+				text: `Detected Yarn & NPM ... \n`
+			});
+			const choosePackageManager = await prompts([
+				{
+					name: `packageManager`,
+					message: `Which package manager do you want to use ? (Strapi Recommends yarn)`,
+					type: `select`,
+					choices: [
+						{
+							title: `Yarn`,
+							value: `yarn`,
+						},
+						{
+							title: `NPM`,
+							value: `npm`,
+						},
+					]
+				}
+			]);
+			config.packageManager = choosePackageManager[`packageManager`];
+			spinner.stopAndPersist({
+				symbol: `\n📦`,
+				text: `Using ${chalk.bold.blueBright(
+					config.packageManager.toUpperCase()
+				)} \n`
+			});
+			return;
+		} else {
+			try {
+				await access(`yarn.lock`, constants.R_OK);
+				config.packageManager = `yarn`;
+				if (!installedPackages.includes(`yarn`)) {
+					await checkForYarnPackage();
+				}
+				return;
+			} catch (error) {
+				config.packageManager = `npm`;
+			}			  
+			spinner.stopAndPersist({
+				symbol: `📦`,
+				text: ` ${chalk.bold.yellow(
+					config.packageManager.toUpperCase()
+				)} detected \n`
+			});
+			return;
+		}
+	}
+};
 const detectStrapiProject = async () => {
 	spinner.start(` 💻 Detecting Strapi project... `);
 	try {

utils/packageDetection.js

@@ -0,0 +1,34 @@
+const { exec } = require(`child_process`);
+const isWindows = process.platform === `win32`;
+
+async function checkPackage(packageName) {
+	return new Promise((resolve) => {
+		const command = isWindows ? `where ${packageName}` : `which ${packageName}`;
+		exec(command, (error) => {
+			if (error) {
+				resolve(false); 
+			} else {
+				resolve(true); 
+			}
+		});
+	});
+}
+
+async function checkInstalledPackages() {
+	const npmExists = await checkPackage(`npm`);
+	const yarnExists = await checkPackage(`yarn`);
+
+	if (npmExists && yarnExists) {
+		return [`npm`, `yarn`]; 
+	} else if (npmExists) {
+		return [`npm`]; 
+	} else if (yarnExists) {
+		return [`yarn`]; 
+	} else {
+		return []; 
+	}
+}
+
+module.exports = {
+	checkInstalledPackages
+};

utils/yarnPackageHelper.js

@@ -0,0 +1,64 @@
+const { exec } = require(`child_process`);
+const { config } = require(`./config`);
+const {checkInstalledPackages} = require(`./packageDetection`);
+const prompts = require(`prompts`);
+const { spinner, chalk } = require(`./utils`);
+
+async function installYarn() {
+	return new Promise((resolve, reject) => {
+		exec(`npm install -g yarn`, (error, stdout, stderr) => {
+			if (error) {
+				console.error(`Error: ${error.message}`);
+				reject(error);
+				return;
+			}
+			if (stderr) {
+				console.error(`Stderr: ${stderr}`);
+				reject(new Error(stderr));
+				return;
+			}
+			resolve(stdout);
+		});
+	});
+}
+
+async function checkForYarnPackage() {
+	if (config.packageManager === `yarn`) {
+		const checkIfYarnIsInstalled = await checkInstalledPackages();
+		let response = ``;
+		if (!checkIfYarnIsInstalled.includes(`yarn`)) {
+			response = await prompts([
+				{
+					name: `installYarnPrompt`,
+					message: `Yarn not installed! Shall we install it for you? (Strapi Recommended)`,
+					active: `Yes`,
+					inactive: `No`,
+					type: `toggle`
+				}
+			]);
+
+			if (response[`installYarnPrompt`] === true) {
+				await installYarn();
+				config.packageManager = `yarn`;
+				spinner.stopAndPersist({
+					text: `\n✅ Yarn installed successfully!\n`
+				});
+			} else {
+				config.packageManager = `npm`;
+			}
+		}
+
+		spinner.stopAndPersist({
+			symbol: `📦`,
+			text: ` Using ${chalk.bold.blueBright(
+				config.packageManager.toUpperCase()
+			)} \n`
+		});
+	}
+}
+
+
+module.exports = {
+	installYarn,
+	checkForYarnPackage
+};