From 9560bd57ed1a075d8b05e387da1ac3e96e7f1253 Mon Sep 17 00:00:00 2001
From: Arman Ozak <arman@armanozak.com>
Date: Mon, 23 Nov 2020 14:39:31 +0300
Subject: [PATCH] fix: use named imports and exports

---
 .../packages/schematics/src/utils/barrel.ts   | 81 +++++++++++++++----
 1 file changed, 65 insertions(+), 16 deletions(-)

diff --git a/npm/ng-packs/packages/schematics/src/utils/barrel.ts b/npm/ng-packs/packages/schematics/src/utils/barrel.ts
index 1681362568..b5ac6a0cc3 100644
--- a/npm/ng-packs/packages/schematics/src/utils/barrel.ts
+++ b/npm/ng-packs/packages/schematics/src/utils/barrel.ts
@@ -16,15 +16,40 @@ export function createBarrelsGenerator(rootPath: string) {
 
 export function generateBarrelFromPath(tree: Tree, indexPath: string) {
   const saveFile = createFileSaver(tree);
-  const dir = tree.getDir(indexPath);
 
-  const _exports: string[] = [];
+  const asterisk = collectAsteriskBarrel(tree, indexPath);
+  const named = collectNamedBarrel(tree, indexPath);
 
-  dir.subfiles.forEach(fragment => {
-    if (!fragment.endsWith('.ts') || fragment === 'index.ts') return;
+  if (asterisk.exports.length + named.exports.length)
+    saveFile(indexPath + '/index.ts', generateBarrelContent(asterisk, named));
+}
 
-    _exports.push(`export * from './${fragment.replace(/\.ts$/, '')}';`);
-  });
+function generateBarrelContent(asterisk: AsteriskBarrel, named: NamedBarrel): string {
+  const namedImports = !named.imports.length
+    ? ''
+    : named.imports.join(`
+`) +
+      `
+`;
+
+  const namedExports = !named.exports.length
+    ? ''
+    : `export { ${named.exports.join(', ')} };
+`;
+
+  const asteriskExports = !asterisk.exports.length
+    ? ''
+    : asterisk.exports.join(`
+`) +
+      `
+`;
+
+  return namedImports + asteriskExports + namedExports;
+}
+
+function collectNamedBarrel(tree: Tree, indexPath: string) {
+  const dir = tree.getDir(indexPath);
+  const barrel = new NamedBarrel();
 
   dir.subdirs.forEach(fragment => {
     const subDirPath = indexPath + '/' + fragment;
@@ -33,18 +58,42 @@ export function generateBarrelFromPath(tree: Tree, indexPath: string) {
     subDir.visit(() => (hasFiles = true));
     if (!hasFiles) return;
 
-    _exports.push(`export * as ${strings.classify(fragment)} from './${fragment}';`);
+    const namespaceFragment = strings.classify(fragment);
+    barrel.imports.push(`import * as ${namespaceFragment} from './${fragment}';`);
+    barrel.exports.push(namespaceFragment);
     generateBarrelFromPath(tree, subDirPath);
   });
 
-  _exports.sort();
+  barrel.imports.sort();
+  barrel.exports.sort();
 
-  if (_exports.length)
-    saveFile(
-      indexPath + '/index.ts',
-      _exports.join(`
-`) +
-        `
-`,
-    );
+  return barrel;
+}
+
+function collectAsteriskBarrel(tree: Tree, indexPath: string) {
+  const dir = tree.getDir(indexPath);
+  const barrel = new AsteriskBarrel();
+
+  dir.subfiles.forEach(fragment => {
+    if (!fragment.endsWith('.ts') || fragment === 'index.ts') return;
+
+    barrel.exports.push(`export * from './${fragment.replace(/\.ts$/, '')}';`);
+  });
+
+  barrel.exports.sort();
+
+  return barrel;
+}
+
+abstract class Barrel {
+  imports: string[] = [];
+  exports: string[] = [];
+}
+
+class AsteriskBarrel extends Barrel {
+  type = 'Asterisk' as const;
+}
+
+class NamedBarrel extends Barrel {
+  type = 'Named' as const;
 }