Fix non-deterministic moduleId assignment

lib/ids/OccurrenceModuleIdsPlugin.js

@@ -81,7 +81,7 @@ class OccurrenceModuleIdsPlugin {
 					] of moduleGraph.getIncomingConnectionsByOriginModule(module)) {
 						if (!originModule) continue;
 						if (!connections.some(c => c.isTargetActive(undefined))) continue;
-						sum += initialChunkChunkMap.get(originModule);
+						sum += initialChunkChunkMap.get(originModule) || 0;
 					}
 					return sum;
 				};

test/configCases/contenthash/module-ids-size/async.js

@@ -0,0 +1,10 @@
+export default function test() {
+	const a = 1;
+	const b = 2;
+	const c = 3;
+	const d = 4;
+	const f = 5;
+	const e = 6;
+
+	return a + b + c + d + f + e;
+}

test/configCases/contenthash/module-ids-size/file-1.js

@@ -0,0 +1,19 @@
+async function test() {
+	const a = 1;
+	const b = 2;
+	const c = 3;
+	const d = 4;
+	const f = 5;
+	const e = 6;
+
+	await import("./async.js");
+
+	return a + b + c + d + f + e;
+}
+
+test();
+
+export { test }
+export default test;
+
+test();

test/configCases/contenthash/module-ids-size/file-2.js

@@ -0,0 +1,5 @@
+import { test } from "./file-1.js";
+
+export default function foobar() {
+	return "test" + test();
+}

test/configCases/contenthash/module-ids-size/file-3.js

@@ -0,0 +1,7 @@
+function test() {
+	return "test";
+}
+
+test();
+
+module.exports = "test";

test/configCases/contenthash/module-ids-size/file.js

@@ -0,0 +1,25 @@
+import file from "./file-1.js";
+import file2 from "./file-2.js";
+
+async function test() {
+	const a = 1;
+	const b = 2;
+	const c = 3;
+	const d = 4;
+	const f = 5;
+	const e = 6;
+
+	await import(/* webpackMode: "eager" */"./async.js");
+	await import(/* webpackMode: "eager" */"./file-3.js");
+
+	return a + b + c + d + f + e;
+}
+
+test();
+
+export { test, file, file2 }
+export default function foo() {
+	return "test";
+}
+
+test();

test/configCases/contenthash/module-ids-size/index.js

@@ -0,0 +1,7 @@
+import img from "./1.jpg";
+import file from "./file.js";
+
+it("should compile", () => {
+	expect(typeof img).toBe("string");
+	expect(typeof file).toBe("function");
+});

test/configCases/contenthash/module-ids-size/test.config.js

@@ -0,0 +1,28 @@
+const findOutputFiles = require("../../../helpers/findOutputFiles");
+
+const allAssets = new Set();
+const allBundles = new Set();
+
+module.exports = {
+	findBundle: function (i, options) {
+		const bundle = findOutputFiles(options, new RegExp(`^bundle${i}`))[0];
+
+		allBundles.add(/\.([^.]+)\./.exec(bundle)[1]);
+
+		let asset;
+
+		switch (i) {
+			case 0:
+				asset = findOutputFiles(options, /^1\.[^.]*\.jpg$/, "img")[0];
+				break;
+		}
+
+		if (asset) allAssets.add(asset);
+
+		return `./${bundle}`;
+	},
+	afterExecute: () => {
+		// Bundles have the same contenthash
+		expect(allBundles.size).toBe(1);
+	}
+};

test/configCases/contenthash/module-ids-size/webpack.config.js

@@ -0,0 +1,37 @@
+/** @type {import("../../../../").Configuration} */
+module.exports = [
+	{
+		output: {
+			filename: "bundle0.[contenthash].a.js",
+			assetModuleFilename: "img/[name].a.[contenthash][ext]"
+		},
+		optimization: {
+			moduleIds: "size"
+		},
+		module: {
+			rules: [
+				{
+					test: /\.jpg$/,
+					type: "asset/resource"
+				}
+			]
+		}
+	},
+	{
+		output: {
+			filename: "bundle1.[contenthash].b.js",
+			assetModuleFilename: "img/[name].a.[contenthash][ext]"
+		},
+		optimization: {
+			moduleIds: "size"
+		},
+		module: {
+			rules: [
+				{
+					test: /\.jpg$/,
+					type: "asset/resource"
+				}
+			]
+		}
+	}
+];