Create preversion script to check exports

It would be easy to forget to add or remove a class from package.json,
index.js, or README.md.  Check that all classes are present before
changing the package version.

Signed-off-by: Kevin Locke <[email protected]>

.eslintrc.json

@@ -20,7 +20,8 @@
   "overrides": [
     {
       "files": [
-        "bin/*.js"
+        "bin/*.js",
+        "scripts/*.js"
       ],
       "rules": {
         // Executable scripts are not expected to have exports

package.json

@@ -76,7 +76,7 @@
     "lint-js": "eslint --report-unused-disable-directives . && echo ESLint passed.",
     "postpublish": "git -C doc push && git push --follow-tags origin main gh-pages && echo Remember to update GitHub Releases from CHANGELOG.md",
     "postversion": "rimraf doc && git clone -b gh-pages -l -q . doc && npm run doc && git -C doc add . && git -C doc commit -n -m \"Docs for v$npm_package_version\"",
-    "preversion": "npm run test-cov && c8 check-coverage --statements 95 && depcheck --ignore-dirs doc --ignores=\"eslint-*,rimraf\" && david && git-branch-is main && hub-ci-status -vv --wait",
+    "preversion": "node ./scripts/preversion.js && npm run test-cov && c8 check-coverage --statements 95 && depcheck --ignore-dirs doc --ignores=\"eslint-*,rimraf\" && david && git-branch-is main && hub-ci-status -vv --wait",
     "test": "npm run lint && npm run test-unit",
     "test-cov": "npm run lint && npm run test-unit-cov",
     "test-unit": "node --throw-deprecation --unhandled-rejections=strict node_modules/mocha/bin/mocha.js --parallel --recursive test",

scripts/preversion.js

@@ -0,0 +1,56 @@
+#!/usr/bin/env node
+/**
+ * @copyright Copyright 2024 Kevin Locke <[email protected]>
+ * @license MIT
+ */
+
+/* eslint-disable no-console */
+
+import { readdir, readFile } from 'node:fs/promises';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import { debuglog } from 'node:util';
+
+const debug = debuglog('openapi-transformers-preversion');
+
+const packagePath = path.dirname(path.dirname(fileURLToPath(import.meta.url)));
+
+const indexJsPath = path.join(packagePath, 'index.js');
+const indexJs = await readFile(indexJsPath, { encoding: 'utf8' });
+
+const packageJsonPath = path.join(packagePath, 'package.json');
+const packageJsonStr = await readFile(packageJsonPath, { encoding: 'utf8' });
+const packageJson = JSON.parse(packageJsonStr);
+
+const readmePath = path.join(packagePath, 'README.md');
+const readme = await readFile(readmePath, { encoding: 'utf8' });
+
+let errors = 0;
+const packageFiles = await readdir(packagePath);
+for (const packageFile of packageFiles) {
+  if (packageFile.slice(-3) === '.js'
+    && packageFile !== 'index.js') {
+    debug('Checking %s...', packageFile);
+
+    const dotPackageFile = `./${packageFile}`;
+
+    if (!indexJs.includes(dotPackageFile)) {
+      console.error('Error: %s not exported from index.js', dotPackageFile);
+      errors += 1;
+    }
+
+    if (packageJson.exports[dotPackageFile] !== dotPackageFile) {
+      console.error('Error: %s not in package.json#exports', dotPackageFile);
+      errors += 1;
+    }
+
+    if (!readme.includes(dotPackageFile)) {
+      console.error('Error: %s not in README.md', dotPackageFile);
+      errors += 1;
+    }
+  }
+}
+
+debug('preversion checks completed with %d errors', errors);
+
+process.exitCode = errors > 0 ? 1 : 0;