From 652b0328ab6d11942c8fe77de71b7187cbc1c802 Mon Sep 17 00:00:00 2001
From: Hiroki Osame <hiroki.osame@gmail.com>
Date: Mon, 7 Aug 2023 15:44:18 +0900
Subject: [PATCH] fix(plugin): only minimize when used as minimizer

---
 .github/workflows/test.yml |  2 +-
 src/plugin.ts              | 35 ++++++++++++-------
 tests/specs/plugin.ts      | 69 ++++++++++++++++++++++++++++++++++++--
 3 files changed, 90 insertions(+), 16 deletions(-)

diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index b064950b..318984e7 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -35,7 +35,7 @@ jobs:
 
     - name: Test
       env:
-        NODE_OPTIONS: --openssl-legacy-provider 
+        NODE_OPTIONS: --openssl-legacy-provider
       run: pnpm test
 
     - name: Test Node.js v16
diff --git a/src/plugin.ts b/src/plugin.ts
index d01f988d..698dca8c 100644
--- a/src/plugin.ts
+++ b/src/plugin.ts
@@ -5,7 +5,7 @@ import {
 } from 'webpack-sources';
 import webpack4 from 'webpack';
 import webpack5 from 'webpack5';
-import { matchObject } from 'webpack/lib/ModuleFilenameHelpers.js';
+import ModuleFilenameHelpers from 'webpack/lib/ModuleFilenameHelpers.js';
 import { version } from '../package.json';
 import type { EsbuildPluginOptions } from './types.js';
 
@@ -47,7 +47,7 @@ const transformAssets = async (
 			isJsFile.test(asset.name)
 			|| (minifyCss && isCssFile.test(asset.name))
 		)
-		&& matchObject(
+		&& ModuleFilenameHelpers.matchObject(
 			{ include, exclude },
 			asset.name,
 		)
@@ -129,17 +129,7 @@ export default function EsbuildPlugin(
 
 	const transform = implementation?.transform ?? defaultEsbuildTransform;
 
-	const hasGranularMinificationConfig = (
-		'minifyIdentifiers' in options
-		|| 'minifySyntax' in options
-		|| 'minifyWhitespace' in options
-	);
-
-	if (!hasGranularMinificationConfig) {
-		options.minify = true;
-	}
-
-	return {
+	const pluginInstance = {
 		apply(compiler: Compiler) {
 			if (!('format' in options)) {
 				const { target } = compiler.options;
@@ -162,6 +152,23 @@ export default function EsbuildPlugin(
 				}
 			}
 
+			/**
+			 * Enable minification by default if used in the minimizer array
+			 * unless further specified in the options
+			 */
+			const usedAsMinimizer = compiler.options.optimization?.minimizer?.includes?.(pluginInstance);
+			if (
+				usedAsMinimizer
+				&& !(
+					'minify' in options
+					|| 'minifyWhitespace' in options
+					|| 'minifyIdentifiers' in options
+					|| 'minifySyntax' in options
+				)
+			) {
+				options.minify = compiler.options.optimization?.minimize;
+			}
+
 			compiler.hooks.compilation.tap(pluginName, (compilation) => {
 				const meta = JSON.stringify({
 					name: 'esbuild-loader',
@@ -230,4 +237,6 @@ export default function EsbuildPlugin(
 			});
 		},
 	};
+
+	return pluginInstance;
 }
diff --git a/tests/specs/plugin.ts b/tests/specs/plugin.ts
index b4cb14d8..98c4b16d 100644
--- a/tests/specs/plugin.ts
+++ b/tests/specs/plugin.ts
@@ -9,7 +9,7 @@ import {
 	configureMiniCssExtractPlugin,
 } from '../utils.js';
 import * as fixtures from '../fixtures.js';
-import type { EsbuildPluginOptions } from '#esbuild-loader';
+import { EsbuildPlugin, type EsbuildPluginOptions } from '#esbuild-loader';
 
 const assertMinified = (code: string) => {
 	expect(code).not.toMatch(/\s{2,}/);
@@ -23,7 +23,72 @@ export default testSuite(({ describe }, webpack: typeof webpack4 | typeof webpac
 	const webpackIs4 = isWebpack4(webpack);
 
 	describe('Plugin', ({ test, describe }) => {
-		describe('Minify JS', ({ test }) => {
+		describe('Minify JS', ({ test, describe }) => {
+			describe('should not minify by default', ({ test }) => {
+				test('minimizer', async () => {
+					const built = await build(
+						fixtures.minification,
+						(config) => {
+							config.optimization = {
+								minimize: false,
+								minimizer: [
+									new EsbuildPlugin(),
+								],
+							};
+						},
+						webpack,
+					);
+
+					expect(built.stats.hasWarnings()).toBe(false);
+					expect(built.stats.hasErrors()).toBe(false);
+
+					const exportedFunction = built.require('/dist/');
+					expect(exportedFunction('hello world')).toBe('hello world');
+					expect(exportedFunction.toString()).toMatch(/\s{2,}/);
+				});
+
+				test('plugin', async () => {
+					const built = await build(
+						fixtures.minification,
+						(config) => {
+							config.plugins?.push(new EsbuildPlugin());
+						},
+						webpack,
+					);
+
+					expect(built.stats.hasWarnings()).toBe(false);
+					expect(built.stats.hasErrors()).toBe(false);
+
+					const exportedFunction = built.require('/dist/');
+					expect(exportedFunction('hello world')).toBe('hello world');
+					expect(exportedFunction.toString()).toMatch(/\s{2,}/);
+				});
+
+				test('plugin with minimize enabled', async () => {
+					const built = await build(
+						fixtures.minification,
+						(config) => {
+							config.optimization = {
+								minimize: true,
+
+								// Remove Terser
+								minimizer: [],
+							};
+
+							config.plugins?.push(new EsbuildPlugin());
+						},
+						webpack,
+					);
+
+					expect(built.stats.hasWarnings()).toBe(false);
+					expect(built.stats.hasErrors()).toBe(false);
+
+					const exportedFunction = built.require('/dist/');
+					expect(exportedFunction('hello world')).toBe('hello world');
+					expect(exportedFunction.toString()).toMatch(/\s{2,}/);
+				});
+			});
+
 			test('minify', async () => {
 				const built = await build(
 					fixtures.minification,