CLI: Always uses "process.cwd" in the "init" command

cli/init.js

@@ -5,12 +5,12 @@ const inquirer = require('inquirer')
 const invariant = require('./invariant')
 const { SERVICE_WORKER_BUILD_PATH } = require('../config/constants')
 
-const CWD = process.env.INIT_CWD || process.cwd()
+const CWD = process.cwd()
 
 module.exports = function init(args) {
   const { publicDir, save } = args
 
-  // When running as a part of "postinstall" script, CWD equals the library's directory.
+  // When running as a part of "postinstall" script, "cwd" equals the library's directory.
   // The "postinstall" script resolves the right absolute public directory path.
   const absolutePublicDir = path.isAbsolute(publicDir)
     ? publicDir

config/scripts/postinstall.js

@@ -1,10 +1,15 @@
 const fs = require('fs')
 const path = require('path')
-const cwd = process.env.INIT_CWD
+const { execSync } = require('child_process')
+
+// When executing the "postinstall" script, the "process.cwd" equals
+// the package directory, not the parent project where the package is installed.
+// NPM stores the parent project directory in the "INIT_CWD" env variable.
+const parentPackageCwd = process.env.INIT_CWD
 
 // 1. Check if "package.json" has "msw.workerDirectory" property set.
 const packageJson = JSON.parse(
-  fs.readFileSync(path.resolve(cwd, 'package.json'), 'utf8'),
+  fs.readFileSync(path.resolve(parentPackageCwd, 'package.json'), 'utf8'),
 )
 
 if (!packageJson.msw || !packageJson.msw.workerDirectory) {
@@ -13,7 +18,7 @@ if (!packageJson.msw || !packageJson.msw.workerDirectory) {
 
 // 2. Check if the worker directory is an existing path.
 const { workerDirectory } = packageJson.msw
-const absoluteWorkerDirectory = path.resolve(cwd, workerDirectory)
+const absoluteWorkerDirectory = path.resolve(parentPackageCwd, workerDirectory)
 
 if (!fs.existsSync(absoluteWorkerDirectory)) {
   return console.error(
@@ -23,10 +28,13 @@ if (!fs.existsSync(absoluteWorkerDirectory)) {
 }
 
 // 3. Update the worker script.
-const init = require('../../cli/init')
+const cliExecutable = path.resolve(process.cwd(), '../../cli/index.js')
+const relativeCliExecutable = path.relative(parentPackageCwd, cliExecutable)
 
 try {
-  init({ publicDir: absoluteWorkerDirectory })
+  execSync(`node ${relativeCliExecutable} init ${absoluteWorkerDirectory}`, {
+    cwd: parentPackageCwd,
+  })
 } catch (error) {
   console.error(
     `[MSW] Failed to automatically update the worker script:\n${error}`,

test/msw-api/cli/init.test.ts

@@ -74,10 +74,8 @@ test('saves the worker directory in package.json when none are present', async (
   await prepare()
 
   const { stderr, stdout } = await promisifyChildProcess(
-    exec(`node cli/index.js init ${getPath('public')} --save`, {
-      env: {
-        INIT_CWD: getPath('.'),
-      },
+    exec(`node ../../../../cli/index.js init ${getPath('public')} --save`, {
+      cwd: getPath('.'),
     }),
   )
 
@@ -113,10 +111,8 @@ test('warns when current public directory does not match the saved directory fro
   await prepare()
 
   const { stderr, stdout } = await promisifyChildProcess(
-    exec(`node cli/index.js init ${getPath('public')} --save`, {
-      env: {
-        INIT_CWD: getPath('.'),
-      },
+    exec(`node ../../../../cli/index.js init ${getPath('public')} --save`, {
+      cwd: getPath('.'),
     }),
   )