feat: support multiple env params

packages/webpack-cli/lib/groups/ConfigGroup.js

@@ -96,7 +96,14 @@ class ConfigGroup extends GroupHelper {
         const configOptions = moduleObj.content;
         if (typeof configOptions === 'function') {
             // when config is a function, pass the env from args to the config function
-            const newOptions = configOptions(this.args.env);
+            let formattedEnv;
+            if (Array.isArray(this.args.env)) {
+                formattedEnv = this.args.env.reduce((envObject, envOption) => {
+                    envObject[envOption] = true;
+                    return envObject;
+                }, {});
+            }
+            const newOptions = configOptions(formattedEnv);
             // When config function returns a promise, resolve it, if not it's resolved by default
             newOptionsObject['options'] = await Promise.resolve(newOptions);
         } else {

packages/webpack-cli/lib/utils/cli-flags.js

@@ -257,6 +257,7 @@ module.exports = {
             name: 'env',
             usage: '--env',
             type: String,
+            multiple: true,
             group: CONFIG_GROUP,
             description: 'Environment passed to the configuration when it is a function',
         },

test/config/type/function-with-env/function-with-env.test.js

@@ -1,5 +1,5 @@
 'use strict';
-const { stat } = require('fs');
+const { existsSync } = require('fs');
 const { resolve } = require('path');
 const { run } = require('../../../utils/test-utils');
 
@@ -9,19 +9,13 @@ describe('function configuration', () => {
         expect(stderr).toBeFalsy();
         expect(stdout).toBeTruthy();
         // Should generate the appropriate files
-        stat(resolve(__dirname, './bin/prod.js'), (err, stats) => {
-            expect(err).toBe(null);
-            expect(stats.isFile()).toBe(true);
-        });
+        expect(existsSync(resolve(__dirname, './bin/prod.js'))).toBeTruthy();
     });
     it('is able to understand a configuration file as a function', () => {
         const { stderr, stdout } = run(__dirname, ['--env', 'isDev']);
         expect(stderr).toBeFalsy();
         expect(stdout).toBeTruthy();
         // Should generate the appropriate files
-        stat(resolve(__dirname, './bin/dev.js'), (err, stats) => {
-            expect(err).toBe(null);
-            expect(stats.isFile()).toBe(true);
-        });
+        expect(existsSync(resolve(__dirname, './bin/dev.js'))).toBeTruthy();
     });
 });

test/config/type/function-with-env/webpack.config.js

@@ -1,5 +1,5 @@
 module.exports = (env) => {
-    if (env === 'isProd') {
+    if (env.isProd) {
         return {
             entry: './a.js',
             output: {