feat(webpack-cli): allow multiple entry flags

packages/webpack-cli/README.md

@@ -35,7 +35,7 @@ Available Commands
 
 Options
 
-  --entry string           The entry point of your application.
+  --entry string[]         The entry point(s) of your application.
   -c, --config string      Provide path to a webpack configuration file
   -m, --merge string       Merge a configuration file using webpack-merge
   --progress               Print compilation progress during build

packages/webpack-cli/__tests__/arg-parser.test.js

@@ -38,6 +38,13 @@ const basicOptions = [
         },
         description: 'custom type flag',
     },
+    {
+        name: 'multiple-flag',
+        usage: '--multiple-flag <value>',
+        type: String,
+        multiple: true,
+        description: 'multiple flag',
+    },
 ];
 
 const helpAndVersionOptions = basicOptions.slice(0);
@@ -176,6 +183,16 @@ describe('arg-parser', () => {
         expect(warnMock.mock.calls.length).toEqual(0);
     });
 
+    it('handles multiple same args', () => {
+        const res = argParser(basicOptions, ['--multiple-flag', 'a.js', '--multiple-flag', 'b.js'], true);
+        expect(res.unknownArgs.length).toEqual(0);
+        expect(res.opts).toEqual({
+            multipleFlag: ['a.js', 'b.js'],
+            stringFlagWithDefault: 'default-value',
+        });
+        expect(warnMock.mock.calls.length).toEqual(0);
+    });
+
     it('calls help callback on --help', () => {
         const helpCb = jest.fn();
         argParser(helpAndVersionOptions, ['--help'], true, '', helpCb);
@@ -192,7 +209,7 @@ describe('arg-parser', () => {
     it('parses webpack args', () => {
         const res = argParser(core, ['--entry', 'test.js', '--hot', '-o', './dist/', '--no-watch'], true);
         expect(res.unknownArgs.length).toEqual(0);
-        expect(res.opts.entry).toEqual('test.js');
+        expect(res.opts.entry).toEqual(['test.js']);
         expect(res.opts.hot).toBeTruthy();
         expect(res.opts.output).toEqual('./dist/');
         expect(res.opts.watch).toBeFalsy();

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

@@ -1,4 +1,5 @@
 const GroupHelper = require('../utils/GroupHelper');
+const chalk = require('chalk');
 const { core, groups } = require('../utils/cli-flags');
 
 class BasicGroup extends GroupHelper {
@@ -35,6 +36,9 @@ class BasicGroup extends GroupHelper {
             }
             if (arg === 'entry') {
                 options[arg] = this.resolveFilePath(args[arg], 'index.js');
+                if (options[arg].length === 0) {
+                    process.stdout.write(chalk.red('\nError: you provided an invalid entry point.\n'));
+                }
             }
         });
         if (outputOptions['dev']) {

packages/webpack-cli/lib/utils/arg-parser.js

@@ -38,13 +38,16 @@ function argParser(options, args, argsOnly = false, name = '', helpFunction = un
     options.reduce((parserInstance, option) => {
         const flags = option.alias ? `-${option.alias}, --${option.name}` : `--${option.name}`;
         const flagsWithType = option.type !== Boolean ? flags + ' <value>' : flags;
-        if (option.type === Boolean || option.type === String) {
+        if ((option.type === Boolean || option.type === String) && !option.multiple) {
             parserInstance.option(flagsWithType, option.description, option.defaultValue);
             if (option.type === Boolean) {
                 // commander requires explicitly adding the negated version of boolean flags
                 const negatedFlag = `--no-${option.name}`;
                 parserInstance.option(negatedFlag, `negates ${option.name}`);
             }
+        } else if (option.multiple) {
+            const multiArg = (value, previous = []) => previous.concat([value]);
+            parserInstance.option(flagsWithType, option.description, multiArg, option.defaultValue);
         } else {
             // in this case the type is a parsing function
             parserInstance.option(flagsWithType, option.description, option.type, option.defaultValue);

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

@@ -74,9 +74,10 @@ module.exports = {
             name: 'entry',
             usage: '--entry <path to entry file>',
             type: String,
+            multiple: true,
             defaultOption: true,
             group: BASIC_GROUP,
-            description: 'The entry point of your application e.g. ./src/main.js',
+            description: 'The entry point(s) of your application e.g. ./src/main.js',
             link: 'https://webpack.js.org/concepts/#entry',
         },
         {

test/entry/flag-entry/entry-with-flag.test.js

@@ -39,9 +39,27 @@ describe('entry flag', () => {
         });
     });
 
-    it('should throw error for invalid entry file', () => {
-        const { stderr, stdout } = run(__dirname, ['--entry', './src/test.js']);
+    it('should load multiple entries provided by user', (done) => {
+        const { stderr, stdout } = run(__dirname, ['--entry', 'src/a.js', '--entry', 'src/b.js']);
         expect(stderr).toBeFalsy();
-        expect(stdout).toContain('not found');
+        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('Hello from a.js');
+            expect(data).toContain('Hello from b.js');
+            done();
+        });
+    });
+
+    it('should throw error for invalid entry file', () => {
+        const { stderr, stdout } = run(__dirname, ['--entry', 'as']);
+        expect(stderr).toBeTruthy();
+        expect(stdout).toContain('you provided an invalid entry point');
     });
 });

test/entry/flag-entry/src/b.js

@@ -0,0 +1 @@
+console.log('Hello from b.js');