Add in file check to make sure all entry points have equivalent files in ./npm folder.

Fail the build if any equivalent missing.

Author: yu-tian113

scripts/rollup/packaging.js

@@ -6,6 +6,7 @@ const join = require('path').join;
 const resolve = require('path').resolve;
 const Bundles = require('./bundles');
 const asyncCopyTo = require('./utils').asyncCopyTo;
+const glob = require('glob');
 
 const UMD_DEV = Bundles.bundleTypes.UMD_DEV;
 const UMD_PROD = Bundles.bundleTypes.UMD_PROD;
@@ -170,27 +171,35 @@ function copyNodePackageTemplate(packageName) {
   const whitelistedFiles = fs.existsSync(packageJson)
     ? require(packageJson).files
     : null;
-  if (whitelistedFiles && whitelistedFiles.length > 0) {
-    const npmFiles = fs.readdirSync(npmFrom);
-    const whitelistedNpmFiles = npmFiles.filter(file => {
-      return (
-        whitelistedFiles.includes(file) || whitelistedFiles.includes(`${file}/`)
-      );
-    });
-    let whitelistedNpmFilesProxies = [];
-    if (whitelistedNpmFiles.length > 0) {
-      whitelistedNpmFilesProxies = whitelistedNpmFiles.reduce(
-        (proxies, file) => {
-          proxies.push(
-            asyncCopyTo(resolve(`${npmFrom}/${file}`), `${to}/${file}`)
-          );
-          return proxies;
-        },
-        whitelistedNpmFilesProxies
+  const npmRootFiles = fs.readdirSync(npmFrom);
+  const packageRootEntries = glob.sync('*.js', {
+    cwd: from,
+  });
+  packageRootEntries.forEach(entry => {
+    // Terminate the build if any entry point in the package root does not have an equivalent in ./npm.
+    // Exceptions: *.fb.js
+    if (!npmRootFiles.includes(entry) && !/.fb.js$/.test(entry)) {
+      console.error(
+        `Entry point ${entry} in package ${packageName} does not have an equivalent in ./npm`
       );
+      process.exit(1);
     }
+  });
+  if (whitelistedFiles && whitelistedFiles.length > 0) {
+    let asyncCopyProxies = [];
+    asyncCopyProxies = npmRootFiles.reduce((proxies, file) => {
+      if (
+        whitelistedFiles.includes(file) ||
+        whitelistedFiles.includes(`${file}/`)
+      ) {
+        proxies.push(
+          asyncCopyTo(resolve(`${npmFrom}/${file}`), `${to}/${file}`)
+        );
+      }
+      return proxies;
+    }, asyncCopyProxies);
     return Promise.all([
-      ...whitelistedNpmFilesProxies,
+      ...asyncCopyProxies,
       asyncCopyTo(resolve(`${from}/package.json`), `${to}/package.json`),
       asyncCopyTo(resolve(`${from}/README.md`), `${to}/README.md`),
       asyncCopyTo(resolve('./LICENSE'), `${to}/LICENSE`),