chore: return with an exit code of 1 on supplying an unknown command

Author: jamesgeorge007

packages/@vue/cli/__tests__/__e2e__/args.spec.js

@@ -0,0 +1,14 @@
+const path = require('path')
+const execa = require('execa')
+
+const CLI_PATH = path.resolve(__dirname, '..', '..', 'bin', 'vue.js')
+
+const runAsync = async (args, options) => execa(CLI_PATH, args, options)
+
+test('suggests matching command', async () => {
+  const { code, stdout } = await runAsync(['confgi'], { reject: false })
+
+  // Assertions
+  expect(code).toBe(1)
+  expect(stdout).toContain('Did you mean config?')
+})

packages/@vue/cli/__tests__/args.spec.js

@@ -224,6 +224,7 @@ program
     console.log(`  ` + chalk.red(`Unknown command ${chalk.yellow(cmd)}.`))
     console.log()
     suggestCommands(cmd)
+    process.exitCode = 1
   })
 
 // add some useful info on help