From aae6e873251a21c1e8d528e5e529dbc74dc166f3 Mon Sep 17 00:00:00 2001
From: Evan Shortiss <evanshortiss@gmail.com>
Date: Tue, 22 Nov 2016 10:29:08 -0800
Subject: [PATCH 1/3] only add vars that are not undefined

---
 package.json | 3 ++-
 tasks/env.js | 5 ++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/package.json b/package.json
index a3e32aa..6ec4f80 100644
--- a/package.json
+++ b/package.json
@@ -29,6 +29,7 @@
   },
   "devDependencies": {
     "grunt": "~0.4.5",
+    "grunt-cli": "~1.2.0",
     "grunt-contrib-clean": "~0.6.0",
     "grunt-contrib-jshint": "~0.11.0",
     "grunt-jscs": "^1.5.0"
@@ -42,4 +43,4 @@
     "ini": "~1.3.0",
     "lodash": "~2.4.1"
   }
-}
\ No newline at end of file
+}
diff --git a/tasks/env.js b/tasks/env.js
index 24cc024..02c1e6a 100644
--- a/tasks/env.js
+++ b/tasks/env.js
@@ -65,7 +65,10 @@ module.exports = function(grunt) {
       } else {
         var data = {};
         data[option] = typeof optionData === 'function' ? optionData() : optionData;
-        _.extend(process.env, data);
+
+        if (typeof data[option] !== undefined) {
+          _.extend(process.env, data);
+        }
       }
     });
   }

From 50eb2c16d3a8de070df8bb4833652867447294c8 Mon Sep 17 00:00:00 2001
From: Evan Shortiss <evanshortiss@gmail.com>
Date: Tue, 22 Nov 2016 10:35:14 -0800
Subject: [PATCH 2/3] add test

---
 Gruntfile.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/Gruntfile.js b/Gruntfile.js
index bda8cf0..be0446e 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -10,6 +10,10 @@ module.exports = function(grunt) {
         globalOption: 'foo'
       },
       testData: {
+        UNDEFINED_OPTION: function() {
+          // logic here might return undefined or not, but for testing we do
+          return undefined;
+        },
         TEST: 'test',
         data: 'bar'
       },
@@ -97,6 +101,12 @@ module.exports = function(grunt) {
     assert.equal(process.env.data, 'bar', 'data should be set');
     delete process.env.globalOption;
     delete process.env.data;
+
+    assert.equal(
+      process.env.hasOwnProperty('undefinedOption'),
+      false,
+      'undefinedOption should not be set on process.env'
+    );
   });
 
   grunt.registerTask('testOptions', function() {

From 8f4ab5beb72759788aa17e6c00ecb6788750deb0 Mon Sep 17 00:00:00 2001
From: Evan Shortiss <evanshortiss@gmail.com>
Date: Tue, 22 Nov 2016 10:45:59 -0800
Subject: [PATCH 3/3] fix test

---
 Gruntfile.js | 4 ++--
 tasks/env.js | 2 +-
 2 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/Gruntfile.js b/Gruntfile.js
index be0446e..5d78c75 100644
--- a/Gruntfile.js
+++ b/Gruntfile.js
@@ -103,9 +103,9 @@ module.exports = function(grunt) {
     delete process.env.data;
 
     assert.equal(
-      process.env.hasOwnProperty('undefinedOption'),
+      process.env.hasOwnProperty('UNDEFINED_OPTION'),
       false,
-      'undefinedOption should not be set on process.env'
+      'UNDEFINED_OPTION should not be set on process.env'
     );
   });
 
diff --git a/tasks/env.js b/tasks/env.js
index 02c1e6a..0d9c38f 100644
--- a/tasks/env.js
+++ b/tasks/env.js
@@ -66,7 +66,7 @@ module.exports = function(grunt) {
         var data = {};
         data[option] = typeof optionData === 'function' ? optionData() : optionData;
 
-        if (typeof data[option] !== undefined) {
+        if (data[option] !== undefined) {
           _.extend(process.env, data);
         }
       }