From 10c0c08fc25fea3c18c7c030d4618a401963355a Mon Sep 17 00:00:00 2001
From: isaacs <i@izs.me>
Date: Wed, 18 Sep 2019 10:07:56 -0700
Subject: [PATCH] fix: filter functions and undefined out of makeEnv

---
 index.js      | 7 ++++++-
 test/index.js | 9 ++++++++-
 2 files changed, 14 insertions(+), 2 deletions(-)

diff --git a/index.js b/index.js
index f775155..337de71 100644
--- a/index.js
+++ b/index.js
@@ -458,12 +458,17 @@ function makeEnv (data, opts, prefix, env) {
       return
     }
     var value = opts.config[i]
-    if (value instanceof Stream || Array.isArray(value)) return
+    if (value instanceof Stream || Array.isArray(value) || typeof value === 'function') return
     if (i.match(/umask/)) value = umask.toString(value)
+
     if (!value) value = ''
     else if (typeof value === 'number') value = '' + value
     else if (typeof value !== 'string') value = JSON.stringify(value)
 
+    if (typeof value !== 'string') {
+      return
+    }
+
     value = value.indexOf('\n') !== -1
       ? JSON.stringify(value)
       : value
diff --git a/test/index.js b/test/index.js
index a81f340..4a77ba4 100644
--- a/test/index.js
+++ b/test/index.js
@@ -20,7 +20,10 @@ test('makeEnv', function (t) {
     'myPackage:bar': 2,
     'myPackage:foo': 3,
     'myPackage@1.0.0:baz': 4,
-    'myPackage@1.0.0:foo': 5
+    'myPackage@1.0.0:foo': 5,
+    ignoreThisFunction: () => {},
+    jsonsAsUndefined: { toJSON: () => undefined },
+    jsonsAsFunction: { toJSON: () => () => {} }
   }
 
   const env = lifecycle.makeEnv(pkg, {
@@ -44,6 +47,10 @@ test('makeEnv', function (t) {
   t.equal('4', env.npm_package_config_baz, 'package@version config is included')
   t.equal('5', env.npm_package_config_foo, 'package@version config overrides package config')
 
+  t.equal(env.npm_package_config_ignoreThisFunction, undefined)
+  t.equal(env.npm_package_config_jsonsAsUndefined, undefined)
+  t.equal(env.npm_package_config_jsonsAsFunction, undefined)
+
   t.equal('--inspect-brk --abort-on-uncaught-exception', env.NODE_OPTIONS, 'nodeOptions sets NODE_OPTIONS')
   t.end()
 })