feat(cli): suggest matching commands if the user mistypes (#3860)

Author: jamesgeorge007

packages/@vue/cli/bin/vue.js

@@ -6,6 +6,10 @@
 const chalk = require('chalk')
 const semver = require('semver')
 const requiredVersion = require('../package.json').engines.node
+const didYouMean = require('didyoumean')
+
+// Setting edit distance to 60% of the input string's length
+didYouMean.threshold = 0.6
 
 function checkNodeVersion (wanted, id) {
   if (!semver.satisfies(process.version, wanted)) {
@@ -196,6 +200,7 @@ program
     program.outputHelp()
     console.log(`  ` + chalk.red(`Unknown command ${chalk.yellow(cmd)}.`))
     console.log()
+    suggestCommands(cmd)
   })
 
 // add some useful info on help
@@ -230,6 +235,17 @@ if (!process.argv.slice(2).length) {
   program.outputHelp()
 }
 
+function suggestCommands (cmd) {
+  const availableCommands = program.commands.map(cmd => {
+    return cmd._name
+  })
+
+  const suggestion = didYouMean(cmd, availableCommands)
+  if (suggestion) {
+    console.log(`  ` + chalk.red(`Did you mean ${chalk.yellow(suggestion)}?`))
+  }
+}
+
 function camelize (str) {
   return str.replace(/-(\w)/g, (_, c) => c ? c.toUpperCase() : '')
 }