From 91a2506c824b58b92d719a67cb474997a5b22b0e Mon Sep 17 00:00:00 2001
From: Greg Magolan <gmagolan@gmail.com>
Date: Fri, 15 Nov 2019 21:46:22 -0800
Subject: [PATCH] build: fix for ng_rollup_bundle outside of a sandbox (#33867)

Fixes issue introduced in https://github.com/angular/angular/pull/33808 for ng_rollup_bundle with `-spawn_strategy=standalone`. Without the sandbox (if --spawn_strategy=standalone is set) rollup can resolve to the non-esm .js file generated by ts_library instead of the desired .mjs. This fixes the problem by prioritizing .mjs.

Issue observed is of the flavor:

```
ERROR: modules/benchmarks/src/views/BUILD.bazel:20:1: Bundling JavaScript modules/benchmarks/src/views/bundle.es2015.js
[rollup] failed (Exit 1)
[!] Error: 'enableProdMode' is not exported by bazel-out/darwin-fastbuild/bin/packages/core/index.js
https://rollupjs.org/guide/en/#error-name-is-not-exported-by-module
bazel-out/darwin-fastbuild/bin/modules/benchmarks/src/views/index.mjs (12:9)
10:  * found in the LICENSE file at https://angular.io/license
11:  */
12: import { enableProdMode } from '@angular/core';
             ^
13: import { platformBrowser } from '@angular/platform-browser';
14: import { ViewsBenchmarkModuleNgFactory } from './views-benchmark.ngfactory';
Error: 'enableProdMode' is not exported by bazel-out/darwin-fastbuild/bin/packages/core/index.js
```

PR Close #33867
---
 tools/ng_rollup_bundle/rollup.config.js | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/tools/ng_rollup_bundle/rollup.config.js b/tools/ng_rollup_bundle/rollup.config.js
index daf90067b6..d7e1b05fe1 100644
--- a/tools/ng_rollup_bundle/rollup.config.js
+++ b/tools/ng_rollup_bundle/rollup.config.js
@@ -65,16 +65,19 @@ function resolveBazel(
         return undefined;
       }
     }
-    // Attempt to resovle first as specified, then in the following order
-    // {importee}.mjs, {importee}/index.mjs, {importee}.js, {importee}/index.js.
+    // Attempt in the following order {importee}.mjs, {importee}/index.mjs,
+    // {importee}, {importee}.js, {importee}/index.js. If an .mjs file is
+    // available it should be resolved as rollup cannot handle the .js files
+    // generated by ts_library as they are not esm. When rolling up esm5 files
+    // these are re-rooted so it is not an issue.
     // TODO(gregmagolan): clean this up in the future as the .mjs es2015 outputs
     // along side the .js es5 outputs from ts_library creates this unusual situation for
     // which we can't rely on standard node module resolution to do the right thing.
     // In the future ts_library (or equivalent) should only produce a single flavor of
     // output and ng_rollup_bundle should also just use the use the vanilla rollup_bundle
     // rule without the need for a custom bazel resolver.
-    return tryImportee(importee) || tryImportee(`${importee}.mjs`) ||
-        tryImportee(`${importee}/index.mjs`) || tryImportee(`${importee}.js`) ||
+    return tryImportee(`${importee}.mjs`) || tryImportee(`${importee}/index.mjs`) ||
+        tryImportee(importee) || tryImportee(`${importee}.js`) ||
         tryImportee(`${importee}/index.js`);
   }