Added pnpm package manager + refactored package managers

src/getPackageManager.ts

@@ -0,0 +1,95 @@
+import execa from 'execa';
+import { existsSync } from 'fs';
+
+export type InstallArgsMaker = (packages: string[]) => string[];
+
+export interface PackageManager {
+  name: string;
+  install: string;
+  build: string;
+  start: string;
+  test: string;
+  lockFiles: string[];
+  getInstallArgs: InstallArgsMaker;
+  installed: boolean;
+  checkIsInstalled: () => Promise<any> | void;
+}
+
+export const packageManagers: { [key: string]: PackageManager } = {
+  yarn: {
+    name: 'yarn',
+    install: 'yarn install',
+    build: 'yarn build',
+    start: 'yarn start',
+    test: 'yarn test',
+    lockFiles: ['yarn.lock'],
+    getInstallArgs: packages => ['add', ...packages, '--dev'],
+    installed: false,
+    checkIsInstalled: () => execa('yarnpkg', ['--version']),
+  },
+  pnpm: {
+    name: 'pnpm',
+    install: 'pnpm i',
+    build: 'pnpm run build',
+    start: 'pnpm run start',
+    test: 'pnpm test',
+    lockFiles: ['pnpm-lock.yaml'],
+    getInstallArgs: packages => ['i', ...packages, '--save-dev'],
+    installed: false,
+    checkIsInstalled: () => execa('pnpm', ['--version']),
+  },
+  npm: {
+    name: 'npm',
+    install: 'npm install',
+    build: 'npm run build',
+    start: 'npm run start',
+    test: 'npm test',
+    lockFiles: ['npm-shrinkwrap.json'],
+    getInstallArgs: packages => ['install', ...packages, '--save-dev'],
+    installed: true,
+    checkIsInstalled: () => {},
+  },
+};
+
+let packageManager: PackageManager;
+
+export type PackageManagerName = keyof typeof packageManagers;
+
+export default async function getPackageManager(): Promise<PackageManager> {
+  if (packageManager) {
+    return packageManager;
+  }
+
+  // Test which package managers are installed
+  for (let pmName in packageManagers)
+    try {
+      await packageManagers[pmName].checkIsInstalled();
+      packageManagers[pmName].installed = true;
+    } catch (e) {}
+
+  // If a lock file exists in project, then we can't use any other package manager than that
+  for (let pmName in packageManagers)
+    for (let lockFileName of packageManagers[pmName].lockFiles) {
+      try {
+        if (existsSync(lockFileName))
+          return (packageManager = packageManagers[pmName]);
+      } catch (e) {}
+    }
+
+  // If user specified package_manager with 'npm config set package_manager xxx' - use it
+  try {
+    const pmName = (await execa('npm', ['config', 'get', 'package_manager']))
+      .stdout;
+    if (packageManagers[pmName as any]) {
+      return (packageManager = packageManagers[pmName as any]);
+    }
+  } catch (e) {}
+
+  // Else pick the first one installed
+  for (let pmName in packageManagers)
+    if (packageManagers[pmName].installed)
+      return (packageManager = packageManagers[pmName]);
+
+  // Else pick npm
+  return (packageManager = packageManagers.npm);
+}

src/index.ts

@@ -33,8 +33,7 @@ import {
   getNodeEngineRequirement,
 } from './utils';
 import { concatAllArray } from 'jpjs';
-import getInstallCmd from './getInstallCmd';
-import getInstallArgs from './getInstallArgs';
+import getPackageManager from './getPackageManager';
 import { Input, Select } from 'enquirer';
 import {
   PackageJson,
@@ -240,8 +239,8 @@ prog
 
     const installSpinner = ora(Messages.installing(deps.sort())).start();
     try {
-      const cmd = await getInstallCmd();
-      await execa(cmd, getInstallArgs(cmd, deps));
+      const pm = await getPackageManager();
+      await execa(pm.name, pm.getInstallArgs(deps));
       installSpinner.succeed('Installed dependencies');
       console.log(await Messages.start(pkg));
     } catch (error) {

src/messages.ts

@@ -1,5 +1,5 @@
 import chalk from 'chalk';
-import getInstallCmd from './getInstallCmd';
+import getPackageManager from './getPackageManager';
 import * as Output from './output';
 
 // This was copied from Razzle. Lots of unused stuff.
@@ -61,14 +61,7 @@ Creating ${chalk.bold(chalk.green(projectName))}...
 };
 
 export const start = async function(projectName: string) {
-  const cmd = await getInstallCmd();
-
-  const commands = {
-    install: cmd === 'npm' ? 'npm install' : 'yarn install',
-    build: cmd === 'npm' ? 'npm run build' : 'yarn build',
-    start: cmd === 'npm' ? 'npm run start' : 'yarn start',
-    test: cmd === 'npm' ? 'npm test' : 'yarn test',
-  };
+  const commands = await getPackageManager();
 
   return `
   ${chalk.green('Awesome!')} You're now ready to start coding.