From 8b248a74c9bf7310f051d1ba5311623c6ba2eeab Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 07:15:31 +0100
Subject: [PATCH 01/10] feat: deduplicate binary assets option

---
 src/rollup/types.d.ts                       |  2 +
 src/utils/FileEmitter.ts                    | 93 ++++++++++++++-------
 src/utils/options/mergeOptions.ts           |  1 +
 src/utils/options/normalizeOutputOptions.ts |  1 +
 4 files changed, 67 insertions(+), 30 deletions(-)

diff --git a/src/rollup/types.d.ts b/src/rollup/types.d.ts
index 70805021277..d0c73229131 100644
--- a/src/rollup/types.d.ts
+++ b/src/rollup/types.d.ts
@@ -632,6 +632,7 @@ export interface OutputOptions {
 	banner?: string | AddonFunction;
 	chunkFileNames?: string | ((chunkInfo: PreRenderedChunk) => string);
 	compact?: boolean;
+	deduplicateBinaryAssets?: boolean;
 	// only required for bundle.write
 	dir?: string;
 	/** @deprecated Use the "renderDynamicImport" plugin hook instead. */
@@ -685,6 +686,7 @@ export interface NormalizedOutputOptions {
 	banner: AddonFunction;
 	chunkFileNames: string | ((chunkInfo: PreRenderedChunk) => string);
 	compact: boolean;
+	deduplicateBinaryAssets: boolean;
 	dir: string | undefined;
 	/** @deprecated Use the "renderDynamicImport" plugin hook instead. */
 	dynamicImportFunction: string | undefined;
diff --git a/src/utils/FileEmitter.ts b/src/utils/FileEmitter.ts
index 3880a9ea279..4fb0274bf83 100644
--- a/src/utils/FileEmitter.ts
+++ b/src/utils/FileEmitter.ts
@@ -28,33 +28,45 @@ import { extname } from './path';
 import { isPathFragment } from './relativeId';
 import { makeUnique, renderNamePattern } from './renderNamePattern';
 
+function getSourceHash(source: string | Uint8Array, size?: number): string {
+	return createHash()
+		.update(source)
+		.digest('hex')
+		.slice(0, Math.max(0, size || defaultHashSize));
+}
+
+function prepareAssetFileName(
+	name: string | undefined,
+	source: string | Uint8Array,
+	outputOptions: NormalizedOutputOptions
+): { fileName: string; sourceHash: string | undefined } {
+	let sourceHash: string | undefined;
+	const emittedName = outputOptions.sanitizeFileName(name || 'asset');
+	const fileName = renderNamePattern(
+		typeof outputOptions.assetFileNames === 'function'
+			? outputOptions.assetFileNames({ name, source, type: 'asset' })
+			: outputOptions.assetFileNames,
+		'output.assetFileNames',
+		{
+			ext: () => extname(emittedName).slice(1),
+			extname: () => extname(emittedName),
+			hash: size => (sourceHash = getSourceHash(source, size)),
+			name: () =>
+				emittedName.slice(0, Math.max(0, emittedName.length - extname(emittedName).length))
+		}
+	);
+	return { fileName, sourceHash };
+}
+
 function generateAssetFileName(
 	name: string | undefined,
 	source: string | Uint8Array,
 	outputOptions: NormalizedOutputOptions,
-	bundle: OutputBundleWithPlaceholders
+	bundle: OutputBundleWithPlaceholders,
+	preparedFileName?: string
 ): string {
-	const emittedName = outputOptions.sanitizeFileName(name || 'asset');
-	return makeUnique(
-		renderNamePattern(
-			typeof outputOptions.assetFileNames === 'function'
-				? outputOptions.assetFileNames({ name, source, type: 'asset' })
-				: outputOptions.assetFileNames,
-			'output.assetFileNames',
-			{
-				ext: () => extname(emittedName).slice(1),
-				extname: () => extname(emittedName),
-				hash: size =>
-					createHash()
-						.update(source)
-						.digest('hex')
-						.slice(0, Math.max(0, size || defaultHashSize)),
-				name: () =>
-					emittedName.slice(0, Math.max(0, emittedName.length - extname(emittedName).length))
-			}
-		),
-		bundle
-	);
+	const fileName = preparedFileName || prepareAssetFileName(name, source, outputOptions).fileName;
+	return makeUnique(fileName, bundle);
 }
 
 function reserveFileNameInBundle(
@@ -246,9 +258,6 @@ export class FileEmitter {
 		for (const emittedFile of this.filesByReferenceId.values()) {
 			if (emittedFile.fileName) {
 				reserveFileNameInBundle(emittedFile.fileName, output, this.options.onwarn);
-				if (emittedFile.type === 'asset' && typeof emittedFile.source === 'string') {
-					fileNamesBySource.set(emittedFile.source, emittedFile.fileName);
-				}
 			}
 		}
 		for (const [referenceId, consumedFile] of this.filesByReferenceId) {
@@ -332,17 +341,41 @@ export class FileEmitter {
 		referenceId: string,
 		{ bundle, fileNamesBySource, outputOptions }: FileEmitterOutput
 	): void {
-		const fileName =
-			consumedFile.fileName ||
-			(typeof source === 'string' && fileNamesBySource.get(source)) ||
-			generateAssetFileName(consumedFile.name, source, outputOptions, bundle);
+		let preparedFileName: string | undefined;
+		let sourceHash: string | undefined;
+
+		let fileName = consumedFile.fileName;
+
+		if (!fileName) {
+			if (outputOptions.deduplicateBinaryAssets) {
+				// Reuse source hash if it is going to be needed in the asset file name
+				const prepared = prepareAssetFileName(consumedFile.name, source, outputOptions);
+				preparedFileName = prepared.fileName;
+				sourceHash = prepared.sourceHash || getSourceHash(source);
+				fileName = fileNamesBySource.get(sourceHash);
+			} else if (typeof source === 'string') {
+				fileName = fileNamesBySource.get(source);
+			}
+		}
+
+		fileName ||= generateAssetFileName(
+			consumedFile.name,
+			source,
+			outputOptions,
+			bundle,
+			preparedFileName
+		);
 
 		// We must not modify the original assets to avoid interaction between outputs
 		const assetWithFileName = { ...consumedFile, fileName, source };
 		this.filesByReferenceId.set(referenceId, assetWithFileName);
-		if (typeof source === 'string') {
+
+		if (sourceHash) {
+			fileNamesBySource.set(sourceHash, fileName);
+		} else if (typeof source === 'string') {
 			fileNamesBySource.set(source, fileName);
 		}
+
 		bundle[fileName] = {
 			fileName,
 			name: consumedFile.name,
diff --git a/src/utils/options/mergeOptions.ts b/src/utils/options/mergeOptions.ts
index be429cfb598..ccd2493d08a 100644
--- a/src/utils/options/mergeOptions.ts
+++ b/src/utils/options/mergeOptions.ts
@@ -227,6 +227,7 @@ async function mergeOutputOptions(
 		banner: getOption('banner'),
 		chunkFileNames: getOption('chunkFileNames'),
 		compact: getOption('compact'),
+		deduplicateBinaryAssets: getOption('deduplicateBinaryAssets'),
 		dir: getOption('dir'),
 		dynamicImportFunction: getOption('dynamicImportFunction'),
 		dynamicImportInCjs: getOption('dynamicImportInCjs'),
diff --git a/src/utils/options/normalizeOutputOptions.ts b/src/utils/options/normalizeOutputOptions.ts
index e03e92eba9b..66b97059744 100644
--- a/src/utils/options/normalizeOutputOptions.ts
+++ b/src/utils/options/normalizeOutputOptions.ts
@@ -45,6 +45,7 @@ export async function normalizeOutputOptions(
 		banner: getAddon(config, 'banner'),
 		chunkFileNames: config.chunkFileNames ?? '[name]-[hash].js',
 		compact,
+		deduplicateBinaryAssets: config.deduplicateBinaryAssets ?? false,
 		dir: getDir(config, file),
 		dynamicImportFunction: getDynamicImportFunction(config, inputOptions, format),
 		dynamicImportInCjs: config.dynamicImportInCjs ?? true,

From 670cdf770bee328e169d5eafc9aaf50f4f01061c Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 07:18:02 +0100
Subject: [PATCH 02/10] docs: deduplicateBinaryAssets option

---
 docs/02-javascript-api.md       | 1 +
 docs/999-big-list-of-options.md | 6 ++++++
 2 files changed, 7 insertions(+)

diff --git a/docs/02-javascript-api.md b/docs/02-javascript-api.md
index c4cc17bfae8..321d0643c17 100755
--- a/docs/02-javascript-api.md
+++ b/docs/02-javascript-api.md
@@ -181,6 +181,7 @@ const outputOptions = {
   noConflict,
   preferConst,
   sanitizeFileName,
+  deduplicateBinaryAssets,
   strict,
   systemNullSetters
 };
diff --git a/docs/999-big-list-of-options.md b/docs/999-big-list-of-options.md
index 0eff6b40e3c..3c6ac6bfa20 100755
--- a/docs/999-big-list-of-options.md
+++ b/docs/999-big-list-of-options.md
@@ -1468,6 +1468,12 @@ export default {
 // -> define(['./chunk-or-local-file.js', 'dependency', 'third/dependency'],...
 ```
 
+#### output.deduplicateBinaryAssets
+
+Type: `boolean` <br> Default: `false`
+
+Set to `true` to also deduplicate assets when calling `emitFile` with a `Buffer` as source. By default only string sources are deduplicated.
+
 #### output.esModule
 
 Type: `boolean | "if-default-prop"`<br> CLI: `--esModule`/`--no-esModule`<br> Default: `"if-default-prop"`

From 22f9af6b75a7d2177c0a789cf07ad41c23eb2011 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 08:25:19 +0100
Subject: [PATCH 03/10] test: fix previous tests after new option

---
 test/function/samples/output-options-hook/_config.js | 1 +
 test/misc/optionList.js                              | 4 ++--
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/test/function/samples/output-options-hook/_config.js b/test/function/samples/output-options-hook/_config.js
index ed8e82de12c..bbcc8cf074c 100644
--- a/test/function/samples/output-options-hook/_config.js
+++ b/test/function/samples/output-options-hook/_config.js
@@ -24,6 +24,7 @@ module.exports = {
 					assetFileNames: 'assets/[name]-[hash][extname]',
 					chunkFileNames: '[name]-[hash].js',
 					compact: false,
+					deduplicateBinaryAssets: false,
 					dynamicImportInCjs: true,
 					entryFileNames: '[name].js',
 					esModule: 'if-default-prop',
diff --git a/test/misc/optionList.js b/test/misc/optionList.js
index 9cf18ae43ca..f7770c19c85 100644
--- a/test/misc/optionList.js
+++ b/test/misc/optionList.js
@@ -1,6 +1,6 @@
 exports.input =
 	'acorn, acornInjectPlugins, cache, context, experimentalCacheExpiry, external, inlineDynamicImports, input, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, moduleContext, onwarn, perf, plugins, preserveEntrySignatures, preserveModules, preserveSymlinks, shimMissingExports, strictDeprecations, treeshake, watch';
 exports.flags =
-	'acorn, acornInjectPlugins, amd, assetFileNames, banner, bundleConfigAsCjs, c, cache, chunkFileNames, compact, config, configPlugin, context, d, dir, dynamicImportFunction, dynamicImportInCjs, e, entryFileNames, environment, esModule, experimentalCacheExpiry, exports, extend, external, externalImportAssertions, externalLiveBindings, f, failAfterWarnings, file, footer, format, freeze, g, generatedCode, globals, h, hoistTransitiveImports, i, indent, inlineDynamicImports, input, interop, intro, m, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, minifyInternalExports, moduleContext, n, name, namespaceToStringTag, noConflict, o, onwarn, outro, p, paths, perf, plugin, plugins, preferConst, preserveEntrySignatures, preserveModules, preserveModulesRoot, preserveSymlinks, sanitizeFileName, shimMissingExports, silent, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, stdin, strict, strictDeprecations, systemNullSetters, treeshake, v, validate, w, waitForBundleInput, watch';
+	'acorn, acornInjectPlugins, amd, assetFileNames, banner, bundleConfigAsCjs, c, cache, chunkFileNames, compact, config, configPlugin, context, d, deduplicateBinaryAssets, dir, dynamicImportFunction, dynamicImportInCjs, e, entryFileNames, environment, esModule, experimentalCacheExpiry, exports, extend, external, externalImportAssertions, externalLiveBindings, f, failAfterWarnings, file, footer, format, freeze, g, generatedCode, globals, h, hoistTransitiveImports, i, indent, inlineDynamicImports, input, interop, intro, m, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, minifyInternalExports, moduleContext, n, name, namespaceToStringTag, noConflict, o, onwarn, outro, p, paths, perf, plugin, plugins, preferConst, preserveEntrySignatures, preserveModules, preserveModulesRoot, preserveSymlinks, sanitizeFileName, shimMissingExports, silent, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, stdin, strict, strictDeprecations, systemNullSetters, treeshake, v, validate, w, waitForBundleInput, watch';
 exports.output =
-	'amd, assetFileNames, banner, chunkFileNames, compact, dir, dynamicImportFunction, dynamicImportInCjs, entryFileNames, esModule, exports, extend, externalImportAssertions, externalLiveBindings, file, footer, format, freeze, generatedCode, globals, hoistTransitiveImports, indent, inlineDynamicImports, interop, intro, manualChunks, minifyInternalExports, name, namespaceToStringTag, noConflict, outro, paths, plugins, preferConst, preserveModules, preserveModulesRoot, sanitizeFileName, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, sourcemapPathTransform, strict, systemNullSetters, validate';
+	'amd, assetFileNames, banner, chunkFileNames, compact, deduplicateBinaryAssets, dir, dynamicImportFunction, dynamicImportInCjs, entryFileNames, esModule, exports, extend, externalImportAssertions, externalLiveBindings, file, footer, format, freeze, generatedCode, globals, hoistTransitiveImports, indent, inlineDynamicImports, interop, intro, manualChunks, minifyInternalExports, name, namespaceToStringTag, noConflict, outro, paths, plugins, preferConst, preserveModules, preserveModulesRoot, sanitizeFileName, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, sourcemapPathTransform, strict, systemNullSetters, validate';

From 131b6b25080a2e43bc7d0829f3766b7937637d27 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 08:37:19 +0100
Subject: [PATCH 04/10] test: sample using deduplicateBinaryAssets

---
 .../deduplicate-binary-asset/_config.js        | 18 ++++++++++++++++++
 .../_expected/amd/main.js                      |  9 +++++++++
 .../_expected/amd/myfile                       |  1 +
 .../_expected/cjs/main.js                      |  7 +++++++
 .../_expected/cjs/myfile                       |  1 +
 .../_expected/es/main.js                       |  3 +++
 .../_expected/es/myfile                        |  1 +
 .../_expected/system/main.js                   | 12 ++++++++++++
 .../_expected/system/myfile                    |  1 +
 .../emit-file/deduplicate-binary-asset/main.js |  1 +
 10 files changed, 54 insertions(+)
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_config.js
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
 create mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/main.js

diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_config.js b/test/function/samples/emit-file/deduplicate-binary-asset/_config.js
new file mode 100644
index 00000000000..9bdaef2662d
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_config.js
@@ -0,0 +1,18 @@
+const source = Buffer.from('abc');
+
+module.exports = {
+	description: 'warns if multiple files with the same name are emitted',
+	options: {
+		input: 'main.js',
+		plugins: [
+			{
+				buildStart() {
+					this.emitFile({ type: 'asset', name: 'buildStart', source });
+				},
+				generateBundle() {
+					this.emitFile({ type: 'asset', name: 'generateBundle', source });
+				}
+			}
+		]
+	}
+};
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
new file mode 100644
index 00000000000..f99c5d38fdf
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
@@ -0,0 +1,9 @@
+define(['exports'], function (exports) { 'use strict';
+
+	function hi() { return 2 }
+
+	exports.hi = hi;
+
+	Object.defineProperty(exports, '__esModule', { value: true });
+
+});
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
new file mode 100644
index 00000000000..f2ba8f84ab5
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
@@ -0,0 +1 @@
+abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
new file mode 100644
index 00000000000..ce637f0dcc8
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
@@ -0,0 +1,7 @@
+'use strict';
+
+Object.defineProperty(exports, '__esModule', { value: true });
+
+function hi() { return 2 }
+
+exports.hi = hi;
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
new file mode 100644
index 00000000000..f2ba8f84ab5
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
@@ -0,0 +1 @@
+abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
new file mode 100644
index 00000000000..47c2f790880
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
@@ -0,0 +1,3 @@
+function hi() { return 2 }
+
+export { hi };
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
new file mode 100644
index 00000000000..f2ba8f84ab5
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
@@ -0,0 +1 @@
+abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
new file mode 100644
index 00000000000..0581de90888
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
@@ -0,0 +1,12 @@
+System.register([], function (exports) {
+	'use strict';
+	return {
+		execute: function () {
+
+			exports('hi', hi);
+
+			function hi() { return 2 }
+
+		}
+	};
+});
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
new file mode 100644
index 00000000000..f2ba8f84ab5
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
@@ -0,0 +1 @@
+abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/main.js
new file mode 100644
index 00000000000..be03a2f1d9f
--- /dev/null
+++ b/test/function/samples/emit-file/deduplicate-binary-asset/main.js
@@ -0,0 +1 @@
+export function hi() { return 2 }

From 7ad10a97d83fb66b0116e0d3c56dc25f257866ff Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 13:21:20 +0100
Subject: [PATCH 05/10] chore: remove option and simplify code

---
 docs/02-javascript-api.md                     |  1 -
 docs/999-big-list-of-options.md               |  6 ---
 src/rollup/types.d.ts                         |  2 -
 src/utils/FileEmitter.ts                      | 46 ++++---------------
 src/utils/options/mergeOptions.ts             |  1 -
 src/utils/options/normalizeOutputOptions.ts   |  1 -
 test/cli/samples/watch/bundle-error/main.js   |  1 +
 .../samples/output-options-hook/_config.js    |  1 -
 test/misc/optionList.js                       |  4 +-
 9 files changed, 12 insertions(+), 51 deletions(-)
 create mode 100644 test/cli/samples/watch/bundle-error/main.js

diff --git a/docs/02-javascript-api.md b/docs/02-javascript-api.md
index 321d0643c17..c4cc17bfae8 100755
--- a/docs/02-javascript-api.md
+++ b/docs/02-javascript-api.md
@@ -181,7 +181,6 @@ const outputOptions = {
   noConflict,
   preferConst,
   sanitizeFileName,
-  deduplicateBinaryAssets,
   strict,
   systemNullSetters
 };
diff --git a/docs/999-big-list-of-options.md b/docs/999-big-list-of-options.md
index 3c6ac6bfa20..0eff6b40e3c 100755
--- a/docs/999-big-list-of-options.md
+++ b/docs/999-big-list-of-options.md
@@ -1468,12 +1468,6 @@ export default {
 // -> define(['./chunk-or-local-file.js', 'dependency', 'third/dependency'],...
 ```
 
-#### output.deduplicateBinaryAssets
-
-Type: `boolean` <br> Default: `false`
-
-Set to `true` to also deduplicate assets when calling `emitFile` with a `Buffer` as source. By default only string sources are deduplicated.
-
 #### output.esModule
 
 Type: `boolean | "if-default-prop"`<br> CLI: `--esModule`/`--no-esModule`<br> Default: `"if-default-prop"`
diff --git a/src/rollup/types.d.ts b/src/rollup/types.d.ts
index d0c73229131..70805021277 100644
--- a/src/rollup/types.d.ts
+++ b/src/rollup/types.d.ts
@@ -632,7 +632,6 @@ export interface OutputOptions {
 	banner?: string | AddonFunction;
 	chunkFileNames?: string | ((chunkInfo: PreRenderedChunk) => string);
 	compact?: boolean;
-	deduplicateBinaryAssets?: boolean;
 	// only required for bundle.write
 	dir?: string;
 	/** @deprecated Use the "renderDynamicImport" plugin hook instead. */
@@ -686,7 +685,6 @@ export interface NormalizedOutputOptions {
 	banner: AddonFunction;
 	chunkFileNames: string | ((chunkInfo: PreRenderedChunk) => string);
 	compact: boolean;
-	deduplicateBinaryAssets: boolean;
 	dir: string | undefined;
 	/** @deprecated Use the "renderDynamicImport" plugin hook instead. */
 	dynamicImportFunction: string | undefined;
diff --git a/src/utils/FileEmitter.ts b/src/utils/FileEmitter.ts
index 4fb0274bf83..cbbb74d5de8 100644
--- a/src/utils/FileEmitter.ts
+++ b/src/utils/FileEmitter.ts
@@ -35,7 +35,7 @@ function getSourceHash(source: string | Uint8Array, size?: number): string {
 		.slice(0, Math.max(0, size || defaultHashSize));
 }
 
-function prepareAssetFileName(
+function pregenerateAssetFileName(
 	name: string | undefined,
 	source: string | Uint8Array,
 	outputOptions: NormalizedOutputOptions
@@ -58,17 +58,6 @@ function prepareAssetFileName(
 	return { fileName, sourceHash };
 }
 
-function generateAssetFileName(
-	name: string | undefined,
-	source: string | Uint8Array,
-	outputOptions: NormalizedOutputOptions,
-	bundle: OutputBundleWithPlaceholders,
-	preparedFileName?: string
-): string {
-	const fileName = preparedFileName || prepareAssetFileName(name, source, outputOptions).fileName;
-	return makeUnique(fileName, bundle);
-}
-
 function reserveFileNameInBundle(
 	fileName: string,
 	{ bundle }: FileEmitterOutput,
@@ -341,41 +330,24 @@ export class FileEmitter {
 		referenceId: string,
 		{ bundle, fileNamesBySource, outputOptions }: FileEmitterOutput
 	): void {
-		let preparedFileName: string | undefined;
-		let sourceHash: string | undefined;
-
 		let fileName = consumedFile.fileName;
 
+		// Deduplicate assets if an explicit fileName is not provided
 		if (!fileName) {
-			if (outputOptions.deduplicateBinaryAssets) {
-				// Reuse source hash if it is going to be needed in the asset file name
-				const prepared = prepareAssetFileName(consumedFile.name, source, outputOptions);
-				preparedFileName = prepared.fileName;
-				sourceHash = prepared.sourceHash || getSourceHash(source);
-				fileName = fileNamesBySource.get(sourceHash);
-			} else if (typeof source === 'string') {
-				fileName = fileNamesBySource.get(source);
+			const pregenerated = pregenerateAssetFileName(consumedFile.name, source, outputOptions);
+			// Reuse source hash if it was computed as part of the asset file name
+			const sourceHash = pregenerated.sourceHash ?? getSourceHash(source);
+			fileName = fileNamesBySource.get(sourceHash);
+			if (!fileName) {
+				fileName = makeUnique(pregenerated.fileName, bundle);
+				fileNamesBySource.set(sourceHash, fileName);
 			}
 		}
 
-		fileName ||= generateAssetFileName(
-			consumedFile.name,
-			source,
-			outputOptions,
-			bundle,
-			preparedFileName
-		);
-
 		// We must not modify the original assets to avoid interaction between outputs
 		const assetWithFileName = { ...consumedFile, fileName, source };
 		this.filesByReferenceId.set(referenceId, assetWithFileName);
 
-		if (sourceHash) {
-			fileNamesBySource.set(sourceHash, fileName);
-		} else if (typeof source === 'string') {
-			fileNamesBySource.set(source, fileName);
-		}
-
 		bundle[fileName] = {
 			fileName,
 			name: consumedFile.name,
diff --git a/src/utils/options/mergeOptions.ts b/src/utils/options/mergeOptions.ts
index ccd2493d08a..be429cfb598 100644
--- a/src/utils/options/mergeOptions.ts
+++ b/src/utils/options/mergeOptions.ts
@@ -227,7 +227,6 @@ async function mergeOutputOptions(
 		banner: getOption('banner'),
 		chunkFileNames: getOption('chunkFileNames'),
 		compact: getOption('compact'),
-		deduplicateBinaryAssets: getOption('deduplicateBinaryAssets'),
 		dir: getOption('dir'),
 		dynamicImportFunction: getOption('dynamicImportFunction'),
 		dynamicImportInCjs: getOption('dynamicImportInCjs'),
diff --git a/src/utils/options/normalizeOutputOptions.ts b/src/utils/options/normalizeOutputOptions.ts
index 66b97059744..e03e92eba9b 100644
--- a/src/utils/options/normalizeOutputOptions.ts
+++ b/src/utils/options/normalizeOutputOptions.ts
@@ -45,7 +45,6 @@ export async function normalizeOutputOptions(
 		banner: getAddon(config, 'banner'),
 		chunkFileNames: config.chunkFileNames ?? '[name]-[hash].js',
 		compact,
-		deduplicateBinaryAssets: config.deduplicateBinaryAssets ?? false,
 		dir: getDir(config, file),
 		dynamicImportFunction: getDynamicImportFunction(config, inputOptions, format),
 		dynamicImportInCjs: config.dynamicImportInCjs ?? true,
diff --git a/test/cli/samples/watch/bundle-error/main.js b/test/cli/samples/watch/bundle-error/main.js
new file mode 100644
index 00000000000..a4012bff06c
--- /dev/null
+++ b/test/cli/samples/watch/bundle-error/main.js
@@ -0,0 +1 @@
+export default 42;
\ No newline at end of file
diff --git a/test/function/samples/output-options-hook/_config.js b/test/function/samples/output-options-hook/_config.js
index bbcc8cf074c..ed8e82de12c 100644
--- a/test/function/samples/output-options-hook/_config.js
+++ b/test/function/samples/output-options-hook/_config.js
@@ -24,7 +24,6 @@ module.exports = {
 					assetFileNames: 'assets/[name]-[hash][extname]',
 					chunkFileNames: '[name]-[hash].js',
 					compact: false,
-					deduplicateBinaryAssets: false,
 					dynamicImportInCjs: true,
 					entryFileNames: '[name].js',
 					esModule: 'if-default-prop',
diff --git a/test/misc/optionList.js b/test/misc/optionList.js
index f7770c19c85..9cf18ae43ca 100644
--- a/test/misc/optionList.js
+++ b/test/misc/optionList.js
@@ -1,6 +1,6 @@
 exports.input =
 	'acorn, acornInjectPlugins, cache, context, experimentalCacheExpiry, external, inlineDynamicImports, input, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, moduleContext, onwarn, perf, plugins, preserveEntrySignatures, preserveModules, preserveSymlinks, shimMissingExports, strictDeprecations, treeshake, watch';
 exports.flags =
-	'acorn, acornInjectPlugins, amd, assetFileNames, banner, bundleConfigAsCjs, c, cache, chunkFileNames, compact, config, configPlugin, context, d, deduplicateBinaryAssets, dir, dynamicImportFunction, dynamicImportInCjs, e, entryFileNames, environment, esModule, experimentalCacheExpiry, exports, extend, external, externalImportAssertions, externalLiveBindings, f, failAfterWarnings, file, footer, format, freeze, g, generatedCode, globals, h, hoistTransitiveImports, i, indent, inlineDynamicImports, input, interop, intro, m, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, minifyInternalExports, moduleContext, n, name, namespaceToStringTag, noConflict, o, onwarn, outro, p, paths, perf, plugin, plugins, preferConst, preserveEntrySignatures, preserveModules, preserveModulesRoot, preserveSymlinks, sanitizeFileName, shimMissingExports, silent, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, stdin, strict, strictDeprecations, systemNullSetters, treeshake, v, validate, w, waitForBundleInput, watch';
+	'acorn, acornInjectPlugins, amd, assetFileNames, banner, bundleConfigAsCjs, c, cache, chunkFileNames, compact, config, configPlugin, context, d, dir, dynamicImportFunction, dynamicImportInCjs, e, entryFileNames, environment, esModule, experimentalCacheExpiry, exports, extend, external, externalImportAssertions, externalLiveBindings, f, failAfterWarnings, file, footer, format, freeze, g, generatedCode, globals, h, hoistTransitiveImports, i, indent, inlineDynamicImports, input, interop, intro, m, makeAbsoluteExternalsRelative, manualChunks, maxParallelFileOps, maxParallelFileReads, minifyInternalExports, moduleContext, n, name, namespaceToStringTag, noConflict, o, onwarn, outro, p, paths, perf, plugin, plugins, preferConst, preserveEntrySignatures, preserveModules, preserveModulesRoot, preserveSymlinks, sanitizeFileName, shimMissingExports, silent, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, stdin, strict, strictDeprecations, systemNullSetters, treeshake, v, validate, w, waitForBundleInput, watch';
 exports.output =
-	'amd, assetFileNames, banner, chunkFileNames, compact, deduplicateBinaryAssets, dir, dynamicImportFunction, dynamicImportInCjs, entryFileNames, esModule, exports, extend, externalImportAssertions, externalLiveBindings, file, footer, format, freeze, generatedCode, globals, hoistTransitiveImports, indent, inlineDynamicImports, interop, intro, manualChunks, minifyInternalExports, name, namespaceToStringTag, noConflict, outro, paths, plugins, preferConst, preserveModules, preserveModulesRoot, sanitizeFileName, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, sourcemapPathTransform, strict, systemNullSetters, validate';
+	'amd, assetFileNames, banner, chunkFileNames, compact, dir, dynamicImportFunction, dynamicImportInCjs, entryFileNames, esModule, exports, extend, externalImportAssertions, externalLiveBindings, file, footer, format, freeze, generatedCode, globals, hoistTransitiveImports, indent, inlineDynamicImports, interop, intro, manualChunks, minifyInternalExports, name, namespaceToStringTag, noConflict, outro, paths, plugins, preferConst, preserveModules, preserveModulesRoot, sanitizeFileName, sourcemap, sourcemapBaseUrl, sourcemapExcludeSources, sourcemapFile, sourcemapPathTransform, strict, systemNullSetters, validate';

From 12ad13a9d82d9bd4425a9910a705f503338b8a60 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Thu, 10 Nov 2022 13:23:09 +0100
Subject: [PATCH 06/10] docs: update emitFile deduplication note

---
 docs/05-plugin-development.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/05-plugin-development.md b/docs/05-plugin-development.md
index a8c0f3110a5..89839ce7d8a 100644
--- a/docs/05-plugin-development.md
+++ b/docs/05-plugin-development.md
@@ -732,7 +732,7 @@ If there are no dynamic imports, this will create exactly three chunks where the
 
 Note that even though any module id can be used in `implicitlyLoadedAfterOneOf`, Rollup will throw an error if such an id cannot be uniquely associated with a chunk, e.g. because the `id` cannot be reached implicitly or explicitly from the existing static entry points, or because the file is completely tree-shaken. Using only entry points, either defined by the user or of previously emitted chunks, will always work, though.
 
-If the `type` is _`asset`_, then this emits an arbitrary new file with the given `source` as content. It is possible to defer setting the `source` via [`this.setAssetSource(referenceId, source)`](guide/en/#thissetassetsource) to a later time to be able to reference a file during the build phase while setting the source separately for each output during the generate phase. Assets with a specified `fileName` will always generate separate files while other emitted assets may be deduplicated with existing assets if they have the same `string` source even if the `name` does not match. If the source is not a string but a typed array or `Buffer`, no deduplication will occur for performance reasons. If an asset without a `fileName` is not deduplicated, the [`output.assetFileNames`](guide/en/#outputassetfilenames) name pattern will be used.
+If the `type` is _`asset`_, then this emits an arbitrary new file with the given `source` as content. It is possible to defer setting the `source` via [`this.setAssetSource(referenceId, source)`](guide/en/#thissetassetsource) to a later time to be able to reference a file during the build phase while setting the source separately for each output during the generate phase. Assets with a specified `fileName` will always generate separate files while other emitted assets may be deduplicated with existing assets if they have the same source even if the `name` does not match. If an asset without a `fileName` is not deduplicated, the [`output.assetFileNames`](guide/en/#outputassetfilenames) name pattern will be used.
 
 #### `this.error`
 

From bacaf626c44b8f0b0e765f4a10ac1ad2e2ebe260 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Fri, 11 Nov 2022 10:24:02 +0100
Subject: [PATCH 07/10] chore: remove missplaced test case

---
 .../deduplicate-binary-asset/_config.js        | 18 ------------------
 .../_expected/amd/main.js                      |  9 ---------
 .../_expected/amd/myfile                       |  1 -
 .../_expected/cjs/main.js                      |  7 -------
 .../_expected/cjs/myfile                       |  1 -
 .../_expected/es/main.js                       |  3 ---
 .../_expected/es/myfile                        |  1 -
 .../_expected/system/main.js                   | 12 ------------
 .../_expected/system/myfile                    |  1 -
 .../emit-file/deduplicate-binary-asset/main.js |  1 -
 10 files changed, 54 deletions(-)
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_config.js
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
 delete mode 100644 test/function/samples/emit-file/deduplicate-binary-asset/main.js

diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_config.js b/test/function/samples/emit-file/deduplicate-binary-asset/_config.js
deleted file mode 100644
index 9bdaef2662d..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_config.js
+++ /dev/null
@@ -1,18 +0,0 @@
-const source = Buffer.from('abc');
-
-module.exports = {
-	description: 'warns if multiple files with the same name are emitted',
-	options: {
-		input: 'main.js',
-		plugins: [
-			{
-				buildStart() {
-					this.emitFile({ type: 'asset', name: 'buildStart', source });
-				},
-				generateBundle() {
-					this.emitFile({ type: 'asset', name: 'generateBundle', source });
-				}
-			}
-		]
-	}
-};
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
deleted file mode 100644
index f99c5d38fdf..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/main.js
+++ /dev/null
@@ -1,9 +0,0 @@
-define(['exports'], function (exports) { 'use strict';
-
-	function hi() { return 2 }
-
-	exports.hi = hi;
-
-	Object.defineProperty(exports, '__esModule', { value: true });
-
-});
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
deleted file mode 100644
index f2ba8f84ab5..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/amd/myfile
+++ /dev/null
@@ -1 +0,0 @@
-abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
deleted file mode 100644
index ce637f0dcc8..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/main.js
+++ /dev/null
@@ -1,7 +0,0 @@
-'use strict';
-
-Object.defineProperty(exports, '__esModule', { value: true });
-
-function hi() { return 2 }
-
-exports.hi = hi;
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
deleted file mode 100644
index f2ba8f84ab5..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/cjs/myfile
+++ /dev/null
@@ -1 +0,0 @@
-abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
deleted file mode 100644
index 47c2f790880..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/main.js
+++ /dev/null
@@ -1,3 +0,0 @@
-function hi() { return 2 }
-
-export { hi };
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
deleted file mode 100644
index f2ba8f84ab5..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/es/myfile
+++ /dev/null
@@ -1 +0,0 @@
-abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
deleted file mode 100644
index 0581de90888..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/main.js
+++ /dev/null
@@ -1,12 +0,0 @@
-System.register([], function (exports) {
-	'use strict';
-	return {
-		execute: function () {
-
-			exports('hi', hi);
-
-			function hi() { return 2 }
-
-		}
-	};
-});
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile b/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
deleted file mode 100644
index f2ba8f84ab5..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/_expected/system/myfile
+++ /dev/null
@@ -1 +0,0 @@
-abc
\ No newline at end of file
diff --git a/test/function/samples/emit-file/deduplicate-binary-asset/main.js b/test/function/samples/emit-file/deduplicate-binary-asset/main.js
deleted file mode 100644
index be03a2f1d9f..00000000000
--- a/test/function/samples/emit-file/deduplicate-binary-asset/main.js
+++ /dev/null
@@ -1 +0,0 @@
-export function hi() { return 2 }

From 9dbffe152fb0fe90ab2768e4843c076e84507d4d Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Fri, 11 Nov 2022 10:24:43 +0100
Subject: [PATCH 08/10] test: extend chunking-form deduplicate-assets

---
 .../emit-file/deduplicate-assets/_config.js   | 35 +++++++++++++++++++
 .../_expected/amd/assets/buffer-d0ca8c2a.txt  |  1 +
 .../amd/assets/otherBuffer-e8d9b528.txt       |  1 +
 .../_expected/amd/named/buffer.txt            |  1 +
 .../_expected/cjs/assets/buffer-d0ca8c2a.txt  |  1 +
 .../cjs/assets/otherBuffer-e8d9b528.txt       |  1 +
 .../_expected/cjs/named/buffer.txt            |  1 +
 .../_expected/es/assets/buffer-d0ca8c2a.txt   |  1 +
 .../es/assets/otherBuffer-e8d9b528.txt        |  1 +
 .../_expected/es/named/buffer.txt             |  1 +
 .../system/assets/buffer-d0ca8c2a.txt         |  1 +
 .../system/assets/otherBuffer-e8d9b528.txt    |  1 +
 .../_expected/system/named/buffer.txt         |  1 +
 13 files changed, 47 insertions(+)
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/buffer-d0ca8c2a.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/otherBuffer-e8d9b528.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/named/buffer.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/buffer-d0ca8c2a.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/otherBuffer-e8d9b528.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/named/buffer.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/buffer-d0ca8c2a.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/otherBuffer-e8d9b528.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/named/buffer.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/buffer-d0ca8c2a.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/otherBuffer-e8d9b528.txt
 create mode 100644 test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/named/buffer.txt

diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_config.js b/test/chunking-form/samples/emit-file/deduplicate-assets/_config.js
index 1f37410f516..41d3beb4ca0 100644
--- a/test/chunking-form/samples/emit-file/deduplicate-assets/_config.js
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_config.js
@@ -5,10 +5,45 @@ module.exports = {
 		plugins: {
 			buildStart() {
 				this.emitFile({ type: 'asset', name: 'string.txt', source: 'string' });
+				this.emitFile({ type: 'asset', name: 'stringSameSource.txt', source: 'string' });
+				this.emitFile({
+					type: 'asset',
+					name: 'sameStringAsBuffer.txt',
+					source: Buffer.from('string') // Test cross Buffer/string deduplication
+				});
+				// Different string source
 				this.emitFile({ type: 'asset', name: 'otherString.txt', source: 'otherString' });
 
+				const bufferSource = () => Buffer.from([0x62, 0x75, 0x66, 0x66, 0x65, 0x72]);
+				this.emitFile({
+					type: 'asset',
+					name: 'buffer.txt',
+					source: bufferSource()
+				});
+				this.emitFile({
+					type: 'asset',
+					name: 'bufferSameSource.txt',
+					source: bufferSource()
+				});
+				this.emitFile({
+					type: 'asset',
+					name: 'sameBufferAsString.txt',
+					source: bufferSource().toString() // Test cross Buffer/string deduplication
+				});
+				// Different buffer source
+				this.emitFile({
+					type: 'asset',
+					name: 'otherBuffer.txt',
+					source: Buffer.from('otherBuffer')
+				});
+
 				// specific file names will not be deduplicated
 				this.emitFile({ type: 'asset', fileName: 'named/string.txt', source: 'named' });
+				this.emitFile({
+					type: 'asset',
+					fileName: 'named/buffer.txt',
+					source: bufferSource()
+				});
 				return null;
 			}
 		}
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/buffer-d0ca8c2a.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/buffer-d0ca8c2a.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/buffer-d0ca8c2a.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/otherBuffer-e8d9b528.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/otherBuffer-e8d9b528.txt
new file mode 100644
index 00000000000..54eb26bae5c
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/assets/otherBuffer-e8d9b528.txt
@@ -0,0 +1 @@
+otherBuffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/named/buffer.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/named/buffer.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/amd/named/buffer.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/buffer-d0ca8c2a.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/buffer-d0ca8c2a.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/buffer-d0ca8c2a.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/otherBuffer-e8d9b528.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/otherBuffer-e8d9b528.txt
new file mode 100644
index 00000000000..54eb26bae5c
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/assets/otherBuffer-e8d9b528.txt
@@ -0,0 +1 @@
+otherBuffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/named/buffer.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/named/buffer.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/cjs/named/buffer.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/buffer-d0ca8c2a.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/buffer-d0ca8c2a.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/buffer-d0ca8c2a.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/otherBuffer-e8d9b528.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/otherBuffer-e8d9b528.txt
new file mode 100644
index 00000000000..54eb26bae5c
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/assets/otherBuffer-e8d9b528.txt
@@ -0,0 +1 @@
+otherBuffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/named/buffer.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/named/buffer.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/es/named/buffer.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/buffer-d0ca8c2a.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/buffer-d0ca8c2a.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/buffer-d0ca8c2a.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/otherBuffer-e8d9b528.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/otherBuffer-e8d9b528.txt
new file mode 100644
index 00000000000..54eb26bae5c
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/assets/otherBuffer-e8d9b528.txt
@@ -0,0 +1 @@
+otherBuffer
\ No newline at end of file
diff --git a/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/named/buffer.txt b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/named/buffer.txt
new file mode 100644
index 00000000000..ea75f1e9c19
--- /dev/null
+++ b/test/chunking-form/samples/emit-file/deduplicate-assets/_expected/system/named/buffer.txt
@@ -0,0 +1 @@
+buffer
\ No newline at end of file

From aa9a4e1c0a0664144f2718a89c9be7b99afa3961 Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Fri, 11 Nov 2022 10:25:18 +0100
Subject: [PATCH 09/10] chore: simplify sourceHash generation

---
 src/utils/FileEmitter.ts | 9 ++++-----
 1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/src/utils/FileEmitter.ts b/src/utils/FileEmitter.ts
index cbbb74d5de8..a14a55fe4b1 100644
--- a/src/utils/FileEmitter.ts
+++ b/src/utils/FileEmitter.ts
@@ -39,7 +39,7 @@ function pregenerateAssetFileName(
 	name: string | undefined,
 	source: string | Uint8Array,
 	outputOptions: NormalizedOutputOptions
-): { fileName: string; sourceHash: string | undefined } {
+): { fileName: string; sourceHash: string } {
 	let sourceHash: string | undefined;
 	const emittedName = outputOptions.sanitizeFileName(name || 'asset');
 	const fileName = renderNamePattern(
@@ -55,6 +55,7 @@ function pregenerateAssetFileName(
 				emittedName.slice(0, Math.max(0, emittedName.length - extname(emittedName).length))
 		}
 	);
+	sourceHash ??= getSourceHash(source);
 	return { fileName, sourceHash };
 }
 
@@ -335,12 +336,10 @@ export class FileEmitter {
 		// Deduplicate assets if an explicit fileName is not provided
 		if (!fileName) {
 			const pregenerated = pregenerateAssetFileName(consumedFile.name, source, outputOptions);
-			// Reuse source hash if it was computed as part of the asset file name
-			const sourceHash = pregenerated.sourceHash ?? getSourceHash(source);
-			fileName = fileNamesBySource.get(sourceHash);
+			fileName = fileNamesBySource.get(pregenerated.sourceHash);
 			if (!fileName) {
 				fileName = makeUnique(pregenerated.fileName, bundle);
-				fileNamesBySource.set(sourceHash, fileName);
+				fileNamesBySource.set(pregenerated.sourceHash, fileName);
 			}
 		}
 

From 7e41f02915eb2a7a7b293947a325a05594d8188a Mon Sep 17 00:00:00 2001
From: patak <matias.capeletto@gmail.com>
Date: Fri, 11 Nov 2022 21:12:02 +0100
Subject: [PATCH 10/10] refactor: precompute hash then slice

---
 src/utils/FileEmitter.ts | 59 ++++++++++++++++++++++------------------
 1 file changed, 32 insertions(+), 27 deletions(-)

diff --git a/src/utils/FileEmitter.ts b/src/utils/FileEmitter.ts
index a14a55fe4b1..8478b8ab199 100644
--- a/src/utils/FileEmitter.ts
+++ b/src/utils/FileEmitter.ts
@@ -28,35 +28,34 @@ import { extname } from './path';
 import { isPathFragment } from './relativeId';
 import { makeUnique, renderNamePattern } from './renderNamePattern';
 
-function getSourceHash(source: string | Uint8Array, size?: number): string {
-	return createHash()
-		.update(source)
-		.digest('hex')
-		.slice(0, Math.max(0, size || defaultHashSize));
+function getSourceHash(source: string | Uint8Array): string {
+	return createHash().update(source).digest('hex');
 }
 
-function pregenerateAssetFileName(
+function generateAssetFileName(
 	name: string | undefined,
 	source: string | Uint8Array,
-	outputOptions: NormalizedOutputOptions
-): { fileName: string; sourceHash: string } {
-	let sourceHash: string | undefined;
+	sourceHash: string,
+	outputOptions: NormalizedOutputOptions,
+	bundle: OutputBundleWithPlaceholders
+): string {
 	const emittedName = outputOptions.sanitizeFileName(name || 'asset');
-	const fileName = renderNamePattern(
-		typeof outputOptions.assetFileNames === 'function'
-			? outputOptions.assetFileNames({ name, source, type: 'asset' })
-			: outputOptions.assetFileNames,
-		'output.assetFileNames',
-		{
-			ext: () => extname(emittedName).slice(1),
-			extname: () => extname(emittedName),
-			hash: size => (sourceHash = getSourceHash(source, size)),
-			name: () =>
-				emittedName.slice(0, Math.max(0, emittedName.length - extname(emittedName).length))
-		}
+	return makeUnique(
+		renderNamePattern(
+			typeof outputOptions.assetFileNames === 'function'
+				? outputOptions.assetFileNames({ name, source, type: 'asset' })
+				: outputOptions.assetFileNames,
+			'output.assetFileNames',
+			{
+				ext: () => extname(emittedName).slice(1),
+				extname: () => extname(emittedName),
+				hash: size => sourceHash.slice(0, Math.max(0, size || defaultHashSize)),
+				name: () =>
+					emittedName.slice(0, Math.max(0, emittedName.length - extname(emittedName).length))
+			}
+		),
+		bundle
 	);
-	sourceHash ??= getSourceHash(source);
-	return { fileName, sourceHash };
 }
 
 function reserveFileNameInBundle(
@@ -335,11 +334,17 @@ export class FileEmitter {
 
 		// Deduplicate assets if an explicit fileName is not provided
 		if (!fileName) {
-			const pregenerated = pregenerateAssetFileName(consumedFile.name, source, outputOptions);
-			fileName = fileNamesBySource.get(pregenerated.sourceHash);
+			const sourceHash = getSourceHash(source);
+			fileName = fileNamesBySource.get(sourceHash);
 			if (!fileName) {
-				fileName = makeUnique(pregenerated.fileName, bundle);
-				fileNamesBySource.set(pregenerated.sourceHash, fileName);
+				fileName = generateAssetFileName(
+					consumedFile.name,
+					source,
+					sourceHash,
+					outputOptions,
+					bundle
+				);
+				fileNamesBySource.set(sourceHash, fileName);
 			}
 		}