feat: allow user to modify generated webpack config

test/webpack/utils.test.js

@@ -0,0 +1,107 @@
+import {validate} from 'webpack';
+import path from 'path';
+import Config from 'webpack-chain';
+
+import {applyConfigureWebpack, applyChainWebpack} from '@lib/webpack/utils';
+
+describe('extending generated webpack config', () => {
+  test('direct mutation on generated webpack config object', async () => {
+    // fake generated webpack config
+    let config = {
+      output: {
+        path: __dirname,
+        filename: 'bundle.js'
+      }
+    };
+
+    /* eslint-disable */
+    const configureWebpack = (generatedConfig, isServer) => {
+      if (!isServer) {
+        generatedConfig.entry = 'entry.js';
+        generatedConfig.output = {
+          path: path.join(__dirname, 'dist'),
+          filename: 'new.bundle.js'
+        };
+      }
+    };
+    /* eslint-enable */
+
+    config = applyConfigureWebpack(configureWebpack, config, false);
+    expect(config).toEqual({
+      entry: 'entry.js',
+      output: {
+        path: path.join(__dirname, 'dist'),
+        filename: 'new.bundle.js'
+      }
+    });
+    const errors = validate(config);
+
+    console.log(errors);
+    expect(errors.length).toBe(0);
+  });
+
+  test('webpack-merge with user webpack config object', async () => {
+    // fake generated webpack config
+    let config = {
+      output: {
+        path: __dirname,
+        filename: 'bundle.js'
+      }
+    };
+
+    /* eslint-disable */
+    const configureWebpack = {
+      entry: 'entry.js',
+      output: {
+        path: path.join(__dirname, 'dist'),
+        filename: 'new.bundle.js'
+      }
+    };
+    /* eslint-enable */
+
+    config = applyConfigureWebpack(configureWebpack, config, false);
+    expect(config).toEqual({
+      entry: 'entry.js',
+      output: {
+        path: path.join(__dirname, 'dist'),
+        filename: 'new.bundle.js'
+      }
+    });
+    const errors = validate(config);
+    expect(errors.length).toBe(0);
+  });
+
+  test('use webpack-chain API', async () => {
+    // fake generated webpack config in webpack-chain format
+    let config = new Config();
+    config.output.path(__dirname).filename('bundle.js');
+
+    // user chainWebpack
+    /* eslint-disable */
+    const chainWebpack = (oldConfig, isServer) => {
+      if (!isServer) {
+        oldConfig.entry('main').add('./entry.js');
+        oldConfig.output
+          .path(path.join(__dirname, 'dist'))
+          .filename('new.bundle.js');
+      }
+    };
+    /* eslint-enable */
+
+    applyChainWebpack(chainWebpack, config, false);
+
+    // transform to webpack configuration object format
+    config = config.toConfig();
+    expect(config).toEqual({
+      output: {
+        path: path.join(__dirname, 'dist'),
+        filename: 'new.bundle.js'
+      },
+      entry: {
+        main: ['./entry.js']
+      }
+    });
+    const errors = validate(config);
+    expect(errors.length).toBe(0);
+  });
+});