From 46f19efa66923a56b1e33aa9d208a83c26cb989e Mon Sep 17 00:00:00 2001
From: Jon Moss <me@jonathanmoss.me>
Date: Fri, 24 Nov 2017 16:29:38 -0500
Subject: [PATCH 1/3]  module: add builtinModules

Provides list of all builtin modules in Node.

Includes modules of all types:
- prefixed (ex: _tls_common)
- deprecated (ex: sys)
- regular (ex: vm)
---
 lib/module.js | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/lib/module.js b/lib/module.js
index 396ca9021ef360..e1279b75bc3271 100644
--- a/lib/module.js
+++ b/lib/module.js
@@ -74,6 +74,12 @@ function Module(id, parent) {
 }
 module.exports = Module;
 
+const builtinModules = Object.keys(NativeModule._source)
+  .filter(NativeModule.nonInternalExists);
+
+Object.freeze(builtinModules);
+Module.builtinModules = builtinModules;
+
 Module._cache = Object.create(null);
 Module._pathCache = Object.create(null);
 Module._extensions = Object.create(null);

From 846dea636e041b6966769baa32ec9c0fba6ee1b6 Mon Sep 17 00:00:00 2001
From: Jon Moss <me@jonathanmoss.me>
Date: Mon, 27 Nov 2017 19:03:09 -0500
Subject: [PATCH 2/3] [squash] add tests and docs

---
 doc/api/modules.md                   | 22 ++++++++++++++++++++++
 test/parallel/test-module-builtin.js | 14 ++++++++++++++
 2 files changed, 36 insertions(+)
 create mode 100644 test/parallel/test-module-builtin.js

diff --git a/doc/api/modules.md b/doc/api/modules.md
index 0b0e62b5bc3402..f9f311d241ce92 100644
--- a/doc/api/modules.md
+++ b/doc/api/modules.md
@@ -817,6 +817,28 @@ The `module.require` method provides a way to load a module as if
 `module` is typically *only* available within a specific module's code, it must
 be explicitly exported in order to be used.
 
+## The `Module` Object
+
+<!-- YAML
+added: v0.3.7
+-->
+
+* {Object}
+
+Provides general utility methods when interacting with instances of
+`Module` -- the `module` variable often seen in file modules. Accessed
+via `require('module')`.
+
+### module.builtinModules
+<!-- YAML
+added: REPLACEME
+-->
+
+* {string[]}
+
+A list of  the names of all modules provided by Node.js. Can be used to verify
+if a module is maintained by a third-party module or not.
+
 [`__dirname`]: #modules_dirname
 [`__filename`]: #modules_filename
 [`Error`]: errors.html#errors_class_error
diff --git a/test/parallel/test-module-builtin.js b/test/parallel/test-module-builtin.js
new file mode 100644
index 00000000000000..5a0e4bdd57af6e
--- /dev/null
+++ b/test/parallel/test-module-builtin.js
@@ -0,0 +1,14 @@
+'use strict';
+require('../common');
+const assert = require('assert');
+const { builtinModules } = require('module');
+
+// Includes modules in lib/ (even deprecated ones)
+assert(builtinModules.includes('http'));
+assert(builtinModules.includes('sys'));
+
+// Does not include internal modules
+assert.deepStrictEqual(
+  builtinModules.filter((mod) => { return mod.startsWith('internal/'); }),
+  []
+);

From 14460415999e5525e5a06948f6b38f70b49a935e Mon Sep 17 00:00:00 2001
From: Jon Moss <me@jonathanmoss.me>
Date: Mon, 27 Nov 2017 19:26:11 -0500
Subject: [PATCH 3/3] nit: addaleax comment

---
 test/parallel/test-module-builtin.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/test/parallel/test-module-builtin.js b/test/parallel/test-module-builtin.js
index 5a0e4bdd57af6e..3897d71ecf4405 100644
--- a/test/parallel/test-module-builtin.js
+++ b/test/parallel/test-module-builtin.js
@@ -9,6 +9,6 @@ assert(builtinModules.includes('sys'));
 
 // Does not include internal modules
 assert.deepStrictEqual(
-  builtinModules.filter((mod) => { return mod.startsWith('internal/'); }),
+  builtinModules.filter((mod) => mod.startsWith('internal/')),
   []
 );