fix(format): force chunk ID to be string

playground/named/a/README.md

@@ -0,0 +1,4 @@
+Named example - "a" version
+===========================
+
+It's the simplest config with the only chunk named with the constant string.

playground/named/a/package.json

@@ -0,0 +1,15 @@
+{
+  "name": "webpack-stats-explorer-playground-named",
+  "version": "1.0.0",
+  "description": "Playground configuration with named chunks plugin for Webpack Stats Explorer",
+  "main": "src/index.js",
+  "scripts": {
+    "test": "echo \"Error: no test specified\" && exit 1",
+    "build": "webpack --config webpack.config.js --verbose --json 1> ../$(basename $(pwd)).json"
+  },
+  "author": "",
+  "license": "MIT",
+  "devDependencies": {
+    "webpack": "4.41.2"
+  }
+}

playground/named/a/webpack.config.js

@@ -0,0 +1,8 @@
+const { NamedChunksPlugin } = require('webpack');
+
+module.exports = {
+  entry: './src/index.js',
+  plugins: [
+    new NamedChunksPlugin((chunk) => 'foobar')
+  ]
+};

playground/named/b/README.md

@@ -0,0 +1,4 @@
+Named example - "b" version
+===========================
+
+Some code was added to the only entrypoint.