[tasks/lib/notice] join all notices with the same separator

tasks/lib/notice/base_notice.txt

@@ -56,4 +56,3 @@ THE SOFTWARE.
 ---
 This product bundles geohash.js which is available under a
 "MIT" license.  For details, see src/ui/public/utils/decode_geo_hash.js.
----

tasks/lib/notice/notice.js

@@ -1,7 +1,7 @@
 import { resolve } from 'path';
 import { readFileSync } from 'fs';
 
-import { generatePackagesNoticeText } from './packages_notice';
+import { generatePackageNoticeText } from './package_notice';
 import { generateNodeNoticeText } from './node_notice';
 
 const BASE_NOTICE = resolve(__dirname, './base_notice.txt');
@@ -20,9 +20,14 @@ const BASE_NOTICE = resolve(__dirname, './base_notice.txt');
  */
 export async function generateNoticeText(options = {}) {
   const { packages, nodeDir } = options;
+
+  const packageNotices = await Promise.all(
+    packages.map(generatePackageNoticeText)
+  );
+
   return [
     readFileSync(BASE_NOTICE, 'utf8'),
-    await generatePackagesNoticeText(packages),
-    generateNodeNoticeText(nodeDir)
-  ].join('');
+    ...packageNotices,
+    generateNodeNoticeText(nodeDir),
+  ].join('\n---\n');
 }

tasks/lib/notice/package_notice.js

@@ -0,0 +1,22 @@
+import { getBundledNotices } from './bundled_notices';
+
+const concatNotices = notices => (
+  notices.map(notice => notice.text).join('\n')
+);
+
+export async function generatePackageNoticeText(pkg) {
+  const bundledNotices = concatNotices(await getBundledNotices(pkg.directory));
+
+  const intro = `This product bundles ${pkg.name}@${pkg.version}`;
+  const license = ` which is available under ${
+    pkg.licenses.length > 1
+    ? `the\n"${pkg.licenses.join('", ')} licenses.`
+    : `a\n"${pkg.licenses[0]}" license.`
+  }`;
+
+  const moreInfo = bundledNotices
+    ? `\n${bundledNotices}\n`
+    : `  For details, see ${pkg.relative}/.`;
+
+  return `${intro}${license}${moreInfo}`;
+}