SplitChunksPlugin shouldn't change entrypoint chunk name

lib/optimize/SplitChunksPlugin.js

@@ -1297,7 +1297,9 @@ module.exports = class SplitChunksPlugin {
 								}
 							} else {
 								// change the chunk to be a part
-								chunk.name = name;
+								if (chunkGraph.getNumberOfEntryModules(chunk) === 0) {
+									chunk.name = name;
+								}
 							}
 						}
 					}

test/configCases/split-chunks/chunk-filename-entrypoint/a.js

@@ -0,0 +1,3 @@
+const c = require("./commons");
+
+module.exports = "a" + c;

test/configCases/split-chunks/chunk-filename-entrypoint/b.js

@@ -0,0 +1,3 @@
+const c = require("./commons");
+
+module.exports = "b" + c;

test/configCases/split-chunks/chunk-filename-entrypoint/c.js

@@ -0,0 +1,3 @@
+const c = require("./commons");
+
+module.exports = "c" + c;

test/configCases/split-chunks/chunk-filename-entrypoint/commons.js

@@ -0,0 +1,2 @@
+/* Large module to trigger chunk generation */
+module.exports = "commons";

test/configCases/split-chunks/chunk-filename-entrypoint/index.js

@@ -0,0 +1,14 @@
+it("should run", function() {
+	Promise.all(
+		[
+			import(/* webpackChunkName: "a" */ "./a"),
+			import(/* webpackChunkName: "b" */ "./b"),
+			import(/* webpackChunkName: "c" */ "./c")
+		]
+	);
+
+	const files = require("fs").readdirSync(__dirname);
+	expect(files).toContain('main.js');
+	expect(files).toContain('a-a_js-2a91f0ff.bundle.js');
+	expect(files).toContain('b-b_js-c441f481.bundle.js');
+});

test/configCases/split-chunks/chunk-filename-entrypoint/test.config.js

@@ -0,0 +1,5 @@
+module.exports = {
+	findBundle: function(i, options) {
+		return ["main.js"];
+	}
+};

test/configCases/split-chunks/chunk-filename-entrypoint/webpack.config.js

@@ -0,0 +1,23 @@
+/** @type {import("../../../../").Configuration} */
+module.exports = {
+	mode: "development",
+	entry: {
+		main: "./index.js"
+	},
+	node: {
+		__dirname: false,
+		__filename: false
+	},
+	output: {
+		filename: "[name].js",
+		chunkFilename: "[name].bundle.js"
+	},
+	optimization: {
+		splitChunks: {
+			chunks: "all",
+			name: "common",
+			maxSize: 2,
+			minSize: 1
+		}
+	}
+};