fix: add extra merge duplicates call after split chunks

lib/WebpackOptionsApply.js

@@ -53,6 +53,7 @@ const DefaultStatsFactoryPlugin = require("./stats/DefaultStatsFactoryPlugin");
 const DefaultStatsPresetPlugin = require("./stats/DefaultStatsPresetPlugin");
 const DefaultStatsPrinterPlugin = require("./stats/DefaultStatsPrinterPlugin");
 
+const { STAGE_BASIC, STAGE_ADVANCED } = require("./OptimizationStages");
 const { cleverMerge } = require("./util/cleverMerge");
 
 /** @typedef {import("../declarations/WebpackOptions").WebpackOptionsNormalized} WebpackOptions */
@@ -434,7 +435,7 @@ class WebpackOptionsApply extends OptionsApply {
 		}
 		if (options.optimization.mergeDuplicateChunks) {
 			const MergeDuplicateChunksPlugin = require("./optimize/MergeDuplicateChunksPlugin");
-			new MergeDuplicateChunksPlugin().apply(compiler);
+			new MergeDuplicateChunksPlugin(STAGE_BASIC).apply(compiler);
 		}
 		if (options.optimization.flagIncludedChunks) {
 			const FlagIncludedChunksPlugin = require("./optimize/FlagIncludedChunksPlugin");
@@ -474,6 +475,10 @@ class WebpackOptionsApply extends OptionsApply {
 			const SplitChunksPlugin = require("./optimize/SplitChunksPlugin");
 			new SplitChunksPlugin(options.optimization.splitChunks).apply(compiler);
 		}
+		if (options.optimization.mergeDuplicateChunks) {
+			const MergeDuplicateChunksPluginAdv = require("./optimize/MergeDuplicateChunksPlugin");
+			new MergeDuplicateChunksPluginAdv(STAGE_ADVANCED).apply(compiler);
+		}
 		if (options.optimization.runtimeChunk) {
 			const RuntimeChunkPlugin = require("./optimize/RuntimeChunkPlugin");
 			new RuntimeChunkPlugin(

lib/optimize/MergeDuplicateChunksPlugin.js

@@ -5,12 +5,15 @@
 
 "use strict";
 
-const { STAGE_BASIC } = require("../OptimizationStages");
 const { runtimeEqual } = require("../util/runtime");
 
 /** @typedef {import("../Compiler")} Compiler */
 
 class MergeDuplicateChunksPlugin {
+	constructor(stage) {
+		this.stage = stage;
+	}
+
 	/**
 	 * @param {Compiler} compiler the compiler
 	 * @returns {void}
@@ -22,7 +25,7 @@ class MergeDuplicateChunksPlugin {
 				compilation.hooks.optimizeChunks.tap(
 					{
 						name: "MergeDuplicateChunksPlugin",
-						stage: STAGE_BASIC
+						stage: this.stage
 					},
 					chunks => {
 						const { chunkGraph, moduleGraph } = compilation;

test/__snapshots__/StatsTestCases.basictest.js.snap

@@ -4724,6 +4724,29 @@ global:
   global (webpack x.x.x) compiled successfully in X ms"
 `;
 
+exports[`StatsTestCases should print correct stats for split-chunks-dedup 1`] = `
+"asset main.js X KiB [emitted] (name: main) (id hint: main)
+asset table--shared X bytes [emitted]
+asset row-359--shared X bytes [emitted]
+asset cell--shared X bytes [emitted]
+asset templater--shared X bytes [emitted]
+runtime modules X KiB 11 modules
+built modules X bytes (javascript) X bytes (share-init) X bytes (consume-shared) [built]
+  cacheable modules X bytes
+    modules by path ./node_modules/ X bytes 4 modules
+    modules by path ./*.js X bytes 2 modules
+  provide-module modules X bytes
+    provide shared module (default) cell@1.0.0 = ./node_modules/cell/index.js X bytes [built] [code generated]
+    provide shared module (default) row@1.0.0 = ./node_modules/row/index.js X bytes [built] [code generated]
+    + 2 modules
+  consume-shared-module modules X bytes
+    consume shared module (default) table@=1.0.0 (strict) (fallback: ./node_modules/...(truncated) X bytes [built] [code generated]
+    consume shared module (default) row@=1.0.0 (strict) (fallback: ./node_modules...(truncated) X bytes [built] [code generated]
+    consume shared module (default) templater@=1.0.0 (strict) (fallback: ./node_modu...(truncated) X bytes [built] [code generated]
+    consume shared module (default) cell@=1.0.0 (strict) (fallback: ./node_modules/...(truncated) X bytes [built] [code generated]
+webpack x.x.x compiled successfully in X ms"
+`;
+
 exports[`StatsTestCases should print correct stats for tree-shaking 1`] = `
 "asset bundle.js X KiB [emitted] (name: main)
 runtime modules X bytes 3 modules

test/statsCases/split-chunks-dedup/index.js

@@ -0,0 +1,5 @@
+export default async () => {
+	const { test } = await import(/* webpackMode: "eager" */'./module')
+
+	test()
+};

test/statsCases/split-chunks-dedup/module.js

@@ -0,0 +1,5 @@
+import { table } from 'table'
+
+export function test() {
+    expect(table([['1']])).toBe('<table><tr><td>1</td></tr></table>')
+}

test/statsCases/split-chunks-dedup/node_modules/cell/index.js

@@ -0,0 +1,5 @@
+const { tmpl } = require('templater')
+
+module.exports.cell = function(cell) {
+    return tmpl(`<td>CELL</td>`, { CELL: cell })
+}

test/statsCases/split-chunks-dedup/node_modules/cell/package.json

@@ -0,0 +1,8 @@
+{
+    "name": "row",
+    "version": "1.0.0",
+    "dependencies": {
+        "cell": "=1.0.0",
+        "templater": "=1.0.0"
+    }
+}

test/statsCases/split-chunks-dedup/node_modules/row/index.js

@@ -0,0 +1,6 @@
+const { cell } = require('cell')
+const { tmpl } = require('templater')
+
+module.exports.row = function(cells) {
+    return tmpl(`<tr>CELLS</tr>`, { CELLS: cells.map(c => cell(c)).join('\n') })
+}

test/statsCases/split-chunks-dedup/node_modules/row/package.json

@@ -0,0 +1,8 @@
+{
+    "name": "row",
+    "version": "1.0.0",
+    "dependencies": {
+        "cell": "=1.0.0",
+        "templater": "=1.0.0"
+    }
+}

test/statsCases/split-chunks-dedup/node_modules/table/index.js

@@ -0,0 +1,6 @@
+const { row } = require('row')
+const { tmpl } = require('templater')
+
+module.exports.table = function(rows) {
+    return tmpl('<table>ROWS</table>', { ROWS: rows.map(r => row(r)).join('\n') })
+}

test/statsCases/split-chunks-dedup/node_modules/table/package.json

@@ -0,0 +1,8 @@
+{
+    "name": "table",
+    "version": "1.0.0",
+    "dependencies": {
+        "row": "=1.0.0",
+        "templater": "=1.0.0"
+    }
+}

test/statsCases/split-chunks-dedup/node_modules/templater/index.js

@@ -0,0 +1,6 @@
+module.exports.tmpl = function(str, params) {
+    Object.keys(params).forEach((k) => {
+        str = str.replace(new RegExp(k, 'g'), params[k])
+    })
+    return str
+}

test/statsCases/split-chunks-dedup/node_modules/templater/package.json

@@ -0,0 +1,4 @@
+{
+    "name": "templater",
+    "version": "1.0.0"
+}

test/statsCases/split-chunks-dedup/package.json

@@ -0,0 +1,9 @@
+{
+  "private": true,
+  "engines": {
+    "node": ">=10.13.0"
+  },
+  "dependencies": {
+    "table": "=2.0.0"
+  }
+}

test/statsCases/split-chunks-dedup/webpack.config.js

@@ -0,0 +1,82 @@
+const { ModuleFederationPlugin } = require("../../../").container;
+const {
+	WEBPACK_MODULE_TYPE_PROVIDE
+} = require("../../../lib/ModuleTypeConstants");
+
+const chunkIdChunkNameMap = new Map();
+const usedSharedModuleNames = new Set();
+
+/** @type {import("../../../").Configuration} */
+module.exports = {
+	entry: {
+		main: "./"
+	},
+	mode: "production",
+	optimization: {
+		splitChunks: {
+			cacheGroups: {
+				defaultVendors: false,
+				main: {
+					name: "main",
+					enforce: true,
+					minChunks: 3
+				}
+			}
+		}
+	},
+	output: {
+		chunkFilename(pathData) {
+			const { chunk } = pathData;
+			if (chunk && "groupsIterable" in chunk) {
+				for (const group of chunk.groupsIterable) {
+					if (group.origins) {
+						for (const origin of group.origins) {
+							if (
+								origin.module.type === WEBPACK_MODULE_TYPE_PROVIDE &&
+								chunk.id
+							) {
+								if (chunkIdChunkNameMap.has(chunk.id)) {
+									return chunkIdChunkNameMap.get(chunk.id);
+								}
+
+								// @ts-expect-error
+								const sharedModuleName = origin.module._name;
+								let suffix = "";
+								if (usedSharedModuleNames.has(sharedModuleName)) {
+									suffix = `-${chunk.id}`;
+								}
+								const chunkName = `${sharedModuleName}${suffix}--shared`;
+								usedSharedModuleNames.add(sharedModuleName);
+								chunkIdChunkNameMap.set(chunk.id, chunkName);
+
+								return chunkName;
+							}
+						}
+					}
+				}
+			}
+			return "[id]--chunk";
+		}
+	},
+	plugins: [
+		new ModuleFederationPlugin({
+			shared: {
+				table: {
+					requiredVersion: "=1.0.0"
+				},
+				cell: {
+					requiredVersion: "=1.0.0"
+				},
+				row: {
+					requiredVersion: "=1.0.0"
+				},
+				templater: {
+					requiredVersion: "=1.0.0"
+				}
+			}
+		})
+	],
+	stats: {
+		assets: true
+	}
+};