From fc4fae5229c66712b18f70262cb9f9132674b291 Mon Sep 17 00:00:00 2001
From: Nitin Kumar <snitin315@gmail.com>
Date: Thu, 5 Mar 2020 16:27:24 +0530
Subject: [PATCH] feat(webpack-cli): add mode argument validation

---
 packages/webpack-cli/lib/utils/cli-flags.js | 13 ++++++++++---
 test/mode/prod/prod.test.js                 | 18 +++++++++++++++++-
 test/mode/prod/src/index.js                 |  4 ++++
 3 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/packages/webpack-cli/lib/utils/cli-flags.js b/packages/webpack-cli/lib/utils/cli-flags.js
index 5264a2146e5..33fd1067e8f 100644
--- a/packages/webpack-cli/lib/utils/cli-flags.js
+++ b/packages/webpack-cli/lib/utils/cli-flags.js
@@ -1,3 +1,4 @@
+const { logger } = require('@webpack-cli/logger');
 const HELP_GROUP = 'help';
 const CONFIG_GROUP = 'config';
 const BASIC_GROUP = 'basic';
@@ -286,11 +287,17 @@ module.exports = {
         {
             name: 'mode',
             usage: '--mode <development | production>',
-            type: String,
+            type: (value) => {
+                if (value === 'development' || value === 'production' || value === 'none') {
+                    return value ;
+                } else {
+                    logger.warn('You provided an invalid value for "mode" option.');
+                    return 'production' ;
+                }
+            },
             group: ZERO_CONFIG_GROUP,
             description: 'Defines the mode to pass to webpack',
-            link: 'https://webpack.js.org/concepts/#mode',
-            acceptedValues: ["development", "production"]
+            link: 'https://webpack.js.org/concepts/#mode'
         },
         {
             name: 'no-mode',
diff --git a/test/mode/prod/prod.test.js b/test/mode/prod/prod.test.js
index 6d6482c2037..e8cff151546 100644
--- a/test/mode/prod/prod.test.js
+++ b/test/mode/prod/prod.test.js
@@ -1,6 +1,6 @@
 'use strict';
 const { run } = require('../../utils/test-utils');
-const { stat } = require('fs');
+const { stat, readFile } = require('fs');
 const { resolve } = require('path');
 describe('mode flags', () => {
     it('should load a production config when --prod is passed', done => {
@@ -25,6 +25,22 @@ describe('mode flags', () => {
         });
     });
 
+    it('should load a production config when --mode=abcd is passed', done => {
+        const { stderr, stdout } = run(__dirname, ['--mode', 'abcd']);
+        expect(stderr).toContain('invalid value for "mode"');
+        expect(stdout).toBeTruthy();
+        stat(resolve(__dirname, './bin/main.js'), (err, stats) => {
+            expect(err).toBe(null);
+            expect(stats.isFile()).toBe(true);
+            done();
+        });
+        readFile(resolve(__dirname, './bin/main.js'), 'utf-8', (err, data) => {
+            expect(err).toBe(null);
+            expect(data).toContain('production');
+            done();
+        });
+    });
+
     it('should load a production config when --mode=production and --prod are passed', done => {
         const { stderr, stdout } = run(__dirname, ['--mode', 'production', '--prod']);
         expect(stderr).toContain('"mode" will be used');
diff --git a/test/mode/prod/src/index.js b/test/mode/prod/src/index.js
index 0a899cfdc75..db78df3c106 100644
--- a/test/mode/prod/src/index.js
+++ b/test/mode/prod/src/index.js
@@ -1 +1,5 @@
 console.log('default');
+
+if (process.env.NODE_ENV === "production") {
+    console.log('production');
+}