Update package:browser field on pre-publish to support webpack 4

package.json

@@ -97,8 +97,9 @@
     "start": "dumi dev",
     "build": "dumi build",
     "compile": "father build && lessc assets/index.less assets/index.css",
+    "browser-field": "node scripts/update-browser-field.js",
     "gh-pages": "npm run build && father doc deploy",
-    "prepublishOnly": "npm run compile && rc-np",
+    "prepublishOnly": "npm run compile && npm run browser-field && rc-np",
     "lint": "eslint src/ --ext .ts,.tsx,.jsx,.js,.md",
     "lint:tsc": "tsc -p tsconfig.json --noEmit",
     "prettier": "prettier --write \"**/*.{ts,tsx,js,jsx,json,md}\"",

scripts/update-browser-field.js

@@ -0,0 +1,46 @@
+#!/usr/bin/env node
+const fs = require('fs');
+const path = require('path');
+
+const rootDir = path.resolve(__dirname, '..');
+const pkgPath = path.join(rootDir, 'package.json');
+
+const pkg = JSON.parse(fs.readFileSync(pkgPath, 'utf8'));
+
+const browserEntries = [];
+
+const addEntry = (from, to) => {
+  browserEntries.push([from, to]);
+};
+
+// Preserve previous behavior of preferring the ES build for the main entry.
+addEntry('./lib/index.js', './es/index.js');
+
+const addDirMappings = (dirPath, browserPrefix, targetPrefix) => {
+  if (!fs.existsSync(dirPath)) {
+    return;
+  }
+
+  fs.readdirSync(dirPath, { withFileTypes: true })
+    .filter((dirent) => dirent.isFile() && dirent.name.endsWith('.js'))
+    .map((dirent) => dirent.name)
+    .sort()
+    .forEach((file) => {
+      const name = path.basename(file, '.js');
+      const target = `${targetPrefix}/${file}`;
+
+      addEntry(`${browserPrefix}/${name}`, target);
+      addEntry(`${browserPrefix}/${name}.js`, target);
+    });
+};
+
+addDirMappings(path.join(rootDir, 'es', 'locale'), './locale', './es/locale');
+addDirMappings(path.join(rootDir, 'es', 'generate'), './generate', './es/generate');
+
+const browser = Object.fromEntries(browserEntries.sort((a, b) => a[0].localeCompare(b[0])));
+
+pkg.browser = browser;
+
+fs.writeFileSync(pkgPath, `${JSON.stringify(pkg, null, 2)}\n`);
+
+console.log(`Updated browser field with ${browserEntries.length} entries.`);