refactor: remove sourcemap option (#305)

BREAKING CHANGE: `sourcemap` option removed

README.md

@@ -344,13 +344,6 @@ Default: `'inline'`
 
 Read more about it in the [esbuild docs](https://esbuild.github.io/api/#legal-comments).
 
-#### sourcemap
-Type: `boolean`
-
-Default: Webpack `devtool` configuration
-
-Whether to emit sourcemaps.
-
 #### css
 Type: `boolean`
 

src/minify-plugin.ts

@@ -56,6 +56,24 @@ class ESBuildMinifyPlugin {
 		compiler.hooks.compilation.tap(pluginName, (compilation) => {
 			compilation.hooks.chunkHash.tap(pluginName, (_, hash) => hash.update(meta));
 
+			/**
+			 * Check if sourcemaps are enabled
+			 * Webpack 4: https://github.com/webpack/webpack/blob/v4.46.0/lib/SourceMapDevToolModuleOptionsPlugin.js#L20
+			 * Webpack 5: https://github.com/webpack/webpack/blob/v5.75.0/lib/SourceMapDevToolModuleOptionsPlugin.js#LL27
+			 */
+			let useSourceMap = false;
+			compilation.hooks.finishModules.tap(
+				pluginName,
+				(modules) => {
+					const firstModule = (
+						Array.isArray(modules)
+							? modules[0]
+							: (modules as Set<webpack5.Module>).values().next().value as webpack5.Module
+					);
+					useSourceMap = firstModule.useSourceMap;
+				},
+			);
+
 			if ('processAssets' in compilation.hooks) {
 				compilation.hooks.processAssets.tapPromise(
 					{
@@ -64,59 +82,52 @@ class ESBuildMinifyPlugin {
 						stage: compilation.constructor.PROCESS_ASSETS_STAGE_OPTIMIZE_SIZE,
 						additionalAssets: true,
 					},
-					async () => await this.transformAssets(compilation),
+					async () => await this.transformAssets(compilation, useSourceMap),
 				);
 
 				compilation.hooks.statsPrinter.tap(pluginName, (statsPrinter) => {
 					statsPrinter.hooks.print
 						.for('asset.info.minimized')
 						.tap(
 							pluginName,
-							(minimized, { green, formatFlag }) => 
-								// @ts-expect-error type incorrectly doesn't accept undefined
-								(
-									minimized
-										// @ts-expect-error type incorrectly doesn't accept undefined
-										? green(formatFlag('minimized'))
-										: undefined
-								),
+							(
+								minimized,
+								{ green, formatFlag },
+							// @ts-expect-error type incorrectly doesn't accept undefined
+							) => (
+								minimized
+									// @ts-expect-error type incorrectly doesn't accept undefined
+									? green(formatFlag('minimized'))
+									: undefined
+							),
 						);
 				});
 			} else {
 				compilation.hooks.optimizeChunkAssets.tapPromise(
 					pluginName,
-					async () => await this.transformAssets(compilation),
+					async () => await this.transformAssets(compilation, useSourceMap),
 				);
 			}
 		});
 	}
 
 	private async transformAssets(
 		compilation: Compilation,
+		useSourceMap: boolean,
 	): Promise<void> {
 		const { compiler } = compilation;
-		const { options: { devtool } } = compiler;
-
 		const sources = 'webpack' in compiler && compiler.webpack.sources;
 		const SourceMapSource = (sources ? sources.SourceMapSource : WP4SourceMapSource);
 		const RawSource = (sources ? sources.RawSource : WP4RawSource);
 
-		const sourcemap = (
-			// TODO: drop support for esbuild sourcemap in future so it all goes through WP API
-			// Might still be necessary when SourceMap plugin is used
-			this.options.sourcemap === undefined
-				? Boolean(devtool && (devtool as string).includes('source-map'))
-				: this.options.sourcemap
-		);
-
 		const {
 			css: minifyCss,
 			include,
 			exclude,
 			...transformOptions
 		} = this.options;
 
-		const assets = (compilation.getAssets() as Asset[]).filter((asset) => (
+		const assets = (compilation.getAssets() as Asset[]).filter(asset => (
 
 			// Filter out already minimized
 			!asset.info.minimized
@@ -153,7 +164,7 @@ class ESBuildMinifyPlugin {
 						? 'css'
 						: transformOptions.loader
 				),
-				sourcemap,
+				sourcemap: useSourceMap,
 				sourcefile: asset.name,
 			});
 
@@ -167,7 +178,7 @@ class ESBuildMinifyPlugin {
 			compilation.updateAsset(
 				asset.name,
 				(
-					sourcemap
+					result.map
 						? new SourceMapSource(
 							result.code,
 							asset.name,

src/types.ts

@@ -15,7 +15,7 @@ export type LoaderOptions = Except<TransformOptions, 'sourcemap' | 'sourcefile'>
 	implementation?: Implementation;
 };
 
-export type MinifyPluginOptions = Except<TransformOptions, 'sourcefile'> & {
+export type MinifyPluginOptions = Except<TransformOptions, 'sourcemap' | 'sourcefile'> & {
 	include?: Filter | Filter[];
 	exclude?: Filter | Filter[];
 	css?: boolean;

tests/index.ts

@@ -2,8 +2,13 @@ import { describe } from 'manten';
 import webpack4 from 'webpack';
 import webpack5 from 'webpack5';
 
+const webpacks = [
+	webpack4,
+	webpack5,
+];
+
 describe('esbuild-loader', ({ describe, runTestSuite }) => {
-	for (const webpack of [webpack4, webpack5]) {
+	for (const webpack of webpacks) {
 		describe(`Webpack ${webpack.version![0]}`, ({ runTestSuite }) => {
 			runTestSuite(import('./specs/loader.js'), webpack);
 			runTestSuite(import('./specs/plugin.js'), webpack);

tests/specs/plugin.ts

@@ -206,39 +206,12 @@ export default testSuite(({ describe }, webpack: typeof webpack4 | typeof webpac
 					expect(file).toContain('//# sourceMappingURL=index.js.map');
 				});
 
-				// TODO: This doesn't work, so maybe we should just remove the option?
-				// test('minify w/ plugin sourcemap option', async () => {
-				// 	const built = await build({
-				// 		'/src/index.js': '',
-				// 	}, (config) => {
-				// 		delete config.devtool;
-				// 		configureEsbuildMinifyPlugin(config, {
-				// 			sourcemap: true,
-				// 		});
-				// 	}, webpack);
-
-				// 	const { stats } = built;
-				// 	expect(stats.hasWarnings()).toBe(false);
-				// 	expect(stats.hasErrors()).toBe(false);
-				// 	expect(
-				// 		Object.keys(stats.compilation.assets),
-				// 	).toStrictEqual([
-				// 		'index.js',
-				// 		// 'index.js.map',
-				// 	]);
-
-				// 	const file = built.fs.readFileSync('/dist/index.js', 'utf8');
-				// 	expect(file).toContain('//# sourceMappingURL=index.js.map');
-				// });
-
 				test('minify w/ source-map option and source-map plugin inline', async () => {
 					const built = await build(
 						fixtures.blank,
 						(config) => {
 							delete config.devtool;
-							configureEsbuildMinifyPlugin(config, {
-								sourcemap: true,
-							});
+							configureEsbuildMinifyPlugin(config);
 
 							config.plugins!.push(
 								new webpack.SourceMapDevToolPlugin({}) as any,
@@ -263,9 +236,7 @@ export default testSuite(({ describe }, webpack: typeof webpack4 | typeof webpac
 						fixtures.blank,
 						(config) => {
 							delete config.devtool;
-							configureEsbuildMinifyPlugin(config, {
-								sourcemap: true,
-							});
+							configureEsbuildMinifyPlugin(config);
 
 							config.plugins!.push(
 								new webpack.SourceMapDevToolPlugin({