adapt /version for ESM

Author: PabloSzx

package-lock.json

@@ -56,6 +56,7 @@
     "@babel/plugin-transform-typescript": "7.15.8",
     "@babel/preset-env": "7.15.8",
     "@babel/register": "7.15.3",
+    "@types/babel__core": "^7.1.16",
     "@types/chai": "4.2.22",
     "@types/mocha": "9.0.0",
     "@types/node": "16.11.1",

package.json

@@ -8,6 +8,7 @@ const ts = require('typescript');
 const babel = require('@babel/core');
 const prettier = require('prettier');
 
+const { getVersionFileBody } = require('./gen-version.js');
 const { readdirRecursive, showDirStats } = require('./utils.js');
 
 const prettierConfig = JSON.parse(
@@ -31,7 +32,12 @@ if (require.main === module) {
     const destPath = path.join(distDirectory, filepath);
 
     fs.mkdirSync(path.dirname(destPath), { recursive: true });
-    if (filepath.endsWith('.ts')) {
+    if (isFullESM && filepath === 'version.ts') {
+      const js = babelTransform(getVersionFileBody(packageJSON.version), {
+        envName: 'esm',
+      });
+      writeGeneratedFile(destPath.replace(/\.ts$/, '.js'), js);
+    } else if (filepath.endsWith('.ts')) {
       if (isFullESM) {
         const js = babelBuild(srcPath, { envName: 'esm' });
         writeGeneratedFile(destPath.replace(/\.ts$/, '.js'), js);
@@ -117,6 +123,15 @@ function babelBuild(srcPath, options) {
   return code + '\n';
 }
 
+function babelTransform(sourceCode, options) {
+  const { code } = babel.transformSync(sourceCode, {
+    babelrc: false,
+    configFile: './.babelrc-npm.json',
+    ...options,
+  });
+  return code + '\n';
+}
+
 function buildPackageJSON(srcFiles) {
   const packageJSON = JSON.parse(
     fs.readFileSync(require.resolve('../package.json'), 'utf-8'),

resources/build-npm.js

@@ -2,16 +2,26 @@
 
 const fs = require('fs');
 
-const { version } = require('../package.json');
-
-const versionMatch = /^(\d+)\.(\d+)\.(\d+)-?(.*)?$/.exec(version);
-if (!versionMatch) {
-  throw new Error('Version does not match semver spec: ' + version);
+if (require.main === module) {
+  fs.writeFileSync('./src/version.ts', getVersionFileBody());
 }
 
-const [, major, minor, patch, preReleaseTag] = versionMatch;
+function getVersionFileBody(
+  /**
+   * @type {string | undefined}
+   */
+  version,
+) {
+  if (!version) version = require('../package.json').version;
+
+  const versionMatch = /^(\d+)\.(\d+)\.(\d+)-?(.*)?$/.exec(version);
+  if (!versionMatch) {
+    throw new Error('Version does not match semver spec: ' + version);
+  }
 
-const body = `
+  const [, major, minor, patch, preReleaseTag] = versionMatch;
+
+  const body = `
 // Note: This file is autogenerated using "resources/gen-version.js" script and
 // automatically updated by "npm version" command.
 
@@ -33,6 +43,7 @@ export const versionInfo = Object.freeze({
 });
 `;
 
-if (require.main === module) {
-  fs.writeFileSync('./src/version.ts', body.trim() + '\n');
+  return body.trim() + '\n';
 }
+
+exports.getVersionFileBody = getVersionFileBody;