From 39e032fe86d826e34dc5690c092ac0c0f6fda8a3 Mon Sep 17 00:00:00 2001
From: Guy Bedford <guybedford@gmail.com>
Date: Wed, 14 Feb 2018 22:55:49 +0200
Subject: [PATCH] module: fix main lookup regression from #18728

Backport-PR-URL: https://github.com/nodejs/node/pull/18923
PR-URL: https://github.com/nodejs/node/pull/18788
Refs: https://github.com/nodejs/node/pull/18728
Reviewed-By: Benjamin Gruenbaum <benjamingr@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
---
 src/module_wrap.cc                               | 12 +++++++-----
 test/es-module/test-esm-main-lookup.mjs          |  6 ++++++
 test/fixtures/es-modules/pjson-main/main.js      |  1 +
 test/fixtures/es-modules/pjson-main/package.json |  3 +++
 4 files changed, 17 insertions(+), 5 deletions(-)
 create mode 100644 test/es-module/test-esm-main-lookup.mjs
 create mode 100644 test/fixtures/es-modules/pjson-main/main.js
 create mode 100644 test/fixtures/es-modules/pjson-main/package.json

diff --git a/src/module_wrap.cc b/src/module_wrap.cc
index 6cf792deef76e0..175475b738b2aa 100644
--- a/src/module_wrap.cc
+++ b/src/module_wrap.cc
@@ -534,7 +534,7 @@ const PackageConfig& GetPackageConfig(Environment* env,
   }
 
   auto entry = env->package_json_cache.emplace(path,
-      PackageConfig { Exists::Yes, IsValid::Yes, has_main, "" });
+      PackageConfig { Exists::Yes, IsValid::Yes, has_main, main_std });
   return entry.first->second;
 }
 
@@ -575,13 +575,15 @@ Maybe<URL> ResolveMain(Environment* env, const URL& search) {
       GetPackageConfig(env, pkg.ToFilePath());
   // Note invalid package.json should throw in resolver
   // currently we silently ignore which is incorrect
-  if (!pjson.exists || !pjson.is_valid || !pjson.has_main) {
+  if (pjson.exists == Exists::No ||
+      pjson.is_valid == IsValid::No ||
+      pjson.has_main == HasMain::No) {
     return Nothing<URL>();
   }
   if (!ShouldBeTreatedAsRelativeOrAbsolutePath(pjson.main)) {
-    return Resolve(env, "./" + pjson.main, search);
+    return Resolve(env, "./" + pjson.main, search, IgnoreMain);
   }
-  return Resolve(env, pjson.main, search);
+  return Resolve(env, pjson.main, search, IgnoreMain);
 }
 
 Maybe<URL> ResolveModule(Environment* env,
@@ -592,7 +594,7 @@ Maybe<URL> ResolveModule(Environment* env,
   do {
     dir = parent;
     Maybe<URL> check =
-        Resolve(env, "./node_modules/" + specifier, dir, IgnoreMain);
+        Resolve(env, "./node_modules/" + specifier, dir, CheckMain);
     if (!check.IsNothing()) {
       const size_t limit = specifier.find('/');
       const size_t spec_len =
diff --git a/test/es-module/test-esm-main-lookup.mjs b/test/es-module/test-esm-main-lookup.mjs
new file mode 100644
index 00000000000000..7c81cb647cff38
--- /dev/null
+++ b/test/es-module/test-esm-main-lookup.mjs
@@ -0,0 +1,6 @@
+// Flags: --experimental-modules
+/* eslint-disable required-modules */
+import assert from 'assert';
+import main from '../fixtures/es-modules/pjson-main';
+
+assert.strictEqual(main, 'main');
diff --git a/test/fixtures/es-modules/pjson-main/main.js b/test/fixtures/es-modules/pjson-main/main.js
new file mode 100644
index 00000000000000..dfdd47b877319c
--- /dev/null
+++ b/test/fixtures/es-modules/pjson-main/main.js
@@ -0,0 +1 @@
+module.exports = 'main';
diff --git a/test/fixtures/es-modules/pjson-main/package.json b/test/fixtures/es-modules/pjson-main/package.json
new file mode 100644
index 00000000000000..c13b8cf6acfd33
--- /dev/null
+++ b/test/fixtures/es-modules/pjson-main/package.json
@@ -0,0 +1,3 @@
+{
+  "main": "main.js"
+}