diff --git a/test/dynamic/createPrefixer-test.js b/test/dynamic/createPrefixer-test.js
index 190fca0..02c6b59 100644
--- a/test/dynamic/createPrefixer-test.js
+++ b/test/dynamic/createPrefixer-test.js
@@ -29,7 +29,7 @@ describe('Dynamic Prefixer', () => {
       expect(new Prefixer({ userAgent: Chrome45 }).prefix(input)).to.eql(prefixed)
     })
     it('should not break if the value is undefined or false', () => {
-      expect(new Prefixer({ userAgent: Chrome14 }).prefix({ width: undefined })).to.not.throw()
+      expect(new Prefixer({ userAgent: Chrome14 }).prefix({ width: undefined })).to.eql({ width: undefined })
     })
     it('should also resolve nested objects', () => {
       const input = {
@@ -371,10 +371,8 @@ describe('Dynamic Prefixer', () => {
       expect(new Prefixer({ userAgent: MSIE10 }).prefix({ display: 'block' })).to.eql({ display: 'block' })
     })
     it('should not throw if display is null or undefined', () => {
-      expect(new Prefixer({ userAgent: Chrome45 }).prefix({ display: null }))
-        .to.eql({ display: null })
-      expect(new Prefixer({ userAgent: Chrome45 }).prefix({ display: undefined }))
-        .to.eql({ display: undefined })
+      expect(new Prefixer({ userAgent: Chrome45 }).prefix({ display: null })).to.eql({ display: null })
+      expect(new Prefixer({ userAgent: Chrome45 }).prefix({ display: undefined })).to.eql({ display: undefined })
     })
   })
   describe('Using Prefixer.prefixAll', () => {
diff --git a/yarn.lock b/yarn.lock
index d82c72a..610ae7c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -65,7 +65,7 @@ ansi-escapes@^1.1.0:
   version "1.4.0"
   resolved "https://registry.yarnpkg.com/ansi-escapes/-/ansi-escapes-1.4.0.tgz#d3a8a83b319aa67793662b13e761c7911422306e"
 
-ansi-regex@*, ansi-regex@^2.0.0:
+ansi-regex@^2.0.0:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/ansi-regex/-/ansi-regex-2.1.1.tgz#c3b33ab5ee360d86e0e628f0468ae7ef27d654df"
 
@@ -1157,9 +1157,9 @@ center-align@^0.1.1:
     align-text "^0.1.3"
     lazy-cache "^1.0.3"
 
-chai@^3.2.0:
-  version "3.5.0"
-  resolved "https://registry.yarnpkg.com/chai/-/chai-3.5.0.tgz#4d02637b067fe958bdbfdd3a40ec56fef7373247"
+chai@3.2.0:
+  version "3.2.0"
+  resolved "https://registry.yarnpkg.com/chai/-/chai-3.2.0.tgz#a91c06acc01057f4f4b67ed7785bd7ff4466b2fb"
   dependencies:
     assertion-error "^1.0.1"
     deep-eql "^0.1.3"
@@ -1504,7 +1504,7 @@ debug@^2.1.1, debug@^2.2.0:
   dependencies:
     ms "0.7.2"
 
-debuglog@*, debuglog@^1.0.1:
+debuglog@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/debuglog/-/debuglog-1.0.1.tgz#aa24ffb9ac3df9a2351837cfb2d279360cd78492"
 
@@ -1763,11 +1763,11 @@ escape-html@^1.0.3, escape-html@~1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/escape-html/-/escape-html-1.0.3.tgz#0258eae4d3d0c0974de1c169188ef0051d1d1988"
 
-escape-string-regexp@1.0.2, escape-string-regexp@^1.0.2:
+escape-string-regexp@1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/escape-string-regexp/-/escape-string-regexp-1.0.2.tgz#4dbc2fe674e71949caf3fb2695ce7f2dc1d9a8d1"
 
-escape-string-regexp@1.0.5, escape-string-regexp@^1.0.5:
+escape-string-regexp@1.0.5, escape-string-regexp@^1.0.2, escape-string-regexp@^1.0.5:
   version "1.0.5"
   resolved "https://registry.yarnpkg.com/escape-string-regexp/-/escape-string-regexp-1.0.5.tgz#1b61c0562190a8dff6ae3bb2cf0200ca130b86d4"
 
@@ -2395,13 +2395,21 @@ glob-parent@^2.0.0:
   dependencies:
     is-glob "^2.0.0"
 
-"glob@3 || 4", glob@3.2.11:
+"glob@3 || 4":
   version "3.2.11"
   resolved "https://registry.yarnpkg.com/glob/-/glob-3.2.11.tgz#4a973f635b9190f715d10987d5c00fd2815ebe3d"
   dependencies:
     inherits "2"
     minimatch "0.3"
 
+glob@3.2.3:
+  version "3.2.3"
+  resolved "https://registry.yarnpkg.com/glob/-/glob-3.2.3.tgz#e313eeb249c7affaa5c475286b0e115b59839467"
+  dependencies:
+    graceful-fs "~2.0.0"
+    inherits "2"
+    minimatch "~0.2.11"
+
 glob@^6.0.1:
   version "6.0.4"
   resolved "https://registry.yarnpkg.com/glob/-/glob-6.0.4.tgz#0f08860f6a155127b2fadd4f9ce24b1aab6e4d22"
@@ -2467,13 +2475,17 @@ graceful-fs@4.1.4:
   version "4.1.4"
   resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-4.1.4.tgz#ef089d2880f033b011823ce5c8fae798da775dbd"
 
+graceful-fs@~2.0.0:
+  version "2.0.3"
+  resolved "https://registry.yarnpkg.com/graceful-fs/-/graceful-fs-2.0.3.tgz#7cd2cdb228a4a3f36e95efa6cc142de7d1a136d0"
+
 "graceful-readlink@>= 1.0.0":
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/graceful-readlink/-/graceful-readlink-1.0.1.tgz#4cafad76bc62f02fa039b2f94e9a3dd3a391a725"
 
-growl@1.9.2:
-  version "1.9.2"
-  resolved "https://registry.yarnpkg.com/growl/-/growl-1.9.2.tgz#0ea7743715db8d8de2c5ede1775e1b45ac85c02f"
+growl@1.8.1:
+  version "1.8.1"
+  resolved "https://registry.yarnpkg.com/growl/-/growl-1.8.1.tgz#4b2dec8d907e93db336624dcec0183502f8c9428"
 
 handlebars@^4.0.3:
   version "4.0.6"
@@ -2551,11 +2563,7 @@ home-or-tmp@^2.0.0:
     os-homedir "^1.0.0"
     os-tmpdir "^1.0.1"
 
-hosted-git-info@^2.1.4:
-  version "2.2.0"
-  resolved "https://registry.yarnpkg.com/hosted-git-info/-/hosted-git-info-2.2.0.tgz#7a0d097863d886c0fabbdcd37bf1758d8becf8a5"
-
-hosted-git-info@~2.1.4, hosted-git-info@~2.1.5:
+hosted-git-info@^2.1.4, hosted-git-info@~2.1.4, hosted-git-info@~2.1.5:
   version "2.1.5"
   resolved "https://registry.yarnpkg.com/hosted-git-info/-/hosted-git-info-2.1.5.tgz#0ba81d90da2e25ab34a332e6ec77936e1598118b"
 
@@ -2637,7 +2645,7 @@ immutable@^3.8.1:
   version "3.8.1"
   resolved "https://registry.yarnpkg.com/immutable/-/immutable-3.8.1.tgz#200807f11ab0f72710ea485542de088075f68cd2"
 
-imurmurhash@*, imurmurhash@^0.1.4:
+imurmurhash@^0.1.4:
   version "0.1.4"
   resolved "https://registry.yarnpkg.com/imurmurhash/-/imurmurhash-0.1.4.tgz#9218b9b2b928a238b13dc4fb6b6d576f231453ea"
 
@@ -3163,10 +3171,6 @@ lodash._baseflatten@~4.2.0:
   version "4.2.1"
   resolved "https://registry.yarnpkg.com/lodash._baseflatten/-/lodash._baseflatten-4.2.1.tgz#54acad5e6ef53532a5b8269c0ad725470cfd9208"
 
-lodash._baseindexof@*:
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/lodash._baseindexof/-/lodash._baseindexof-3.1.0.tgz#fe52b53a1c6761e42618d654e4a25789ed61822c"
-
 lodash._baseuniq@~4.4.0:
   version "4.4.0"
   resolved "https://registry.yarnpkg.com/lodash._baseuniq/-/lodash._baseuniq-4.4.0.tgz#a445294347a2f5311f585fe3225644530b9b8fae"
@@ -3188,14 +3192,10 @@ lodash._baseuniq@~4.6.0:
     lodash._createset "~4.0.0"
     lodash._root "~3.0.0"
 
-lodash._bindcallback@*, lodash._bindcallback@^3.0.0:
+lodash._bindcallback@^3.0.0:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/lodash._bindcallback/-/lodash._bindcallback-3.0.1.tgz#e531c27644cf8b57a99e17ed95b35c748789392e"
 
-lodash._cacheindexof@*:
-  version "3.0.2"
-  resolved "https://registry.yarnpkg.com/lodash._cacheindexof/-/lodash._cacheindexof-3.0.2.tgz#3dc69ac82498d2ee5e3ce56091bafd2adc7bde92"
-
 lodash._createassigner@^3.0.0:
   version "3.1.1"
   resolved "https://registry.yarnpkg.com/lodash._createassigner/-/lodash._createassigner-3.1.1.tgz#838a5bae2fdaca63ac22dee8e19fa4e6d6970b11"
@@ -3204,17 +3204,11 @@ lodash._createassigner@^3.0.0:
     lodash._isiterateecall "^3.0.0"
     lodash.restparam "^3.0.0"
 
-lodash._createcache@*:
-  version "3.1.2"
-  resolved "https://registry.yarnpkg.com/lodash._createcache/-/lodash._createcache-3.1.2.tgz#56d6a064017625e79ebca6b8018e17440bdcf093"
-  dependencies:
-    lodash._getnative "^3.0.0"
-
 lodash._createset@~4.0.0:
   version "4.0.3"
   resolved "https://registry.yarnpkg.com/lodash._createset/-/lodash._createset-4.0.3.tgz#0f4659fbb09d75194fa9e2b88a6644d363c9fe26"
 
-lodash._getnative@*, lodash._getnative@^3.0.0:
+lodash._getnative@^3.0.0:
   version "3.9.1"
   resolved "https://registry.yarnpkg.com/lodash._getnative/-/lodash._getnative-3.9.1.tgz#570bc7dede46d61cdcde687d65d3eecbaa3aaff5"
 
@@ -3248,11 +3242,7 @@ lodash.cond@^4.3.0:
   version "4.5.2"
   resolved "https://registry.yarnpkg.com/lodash.cond/-/lodash.cond-4.5.2.tgz#f471a1da486be60f6ab955d17115523dd1d255d5"
 
-lodash.isarguments@^3.0.0:
-  version "3.1.0"
-  resolved "https://registry.yarnpkg.com/lodash.isarguments/-/lodash.isarguments-3.1.0.tgz#2f573d85c6a24289ff00663b491c1d338ff3458a"
-
-lodash.isarguments@~3.0.7:
+lodash.isarguments@^3.0.0, lodash.isarguments@~3.0.7:
   version "3.0.9"
   resolved "https://registry.yarnpkg.com/lodash.isarguments/-/lodash.isarguments-3.0.9.tgz#3c4994a4210f340d49ccfafa62176296207d8675"
 
@@ -3300,7 +3290,7 @@ lodash.rest@^4.0.0:
   version "4.0.5"
   resolved "https://registry.yarnpkg.com/lodash.rest/-/lodash.rest-4.0.5.tgz#954ef75049262038c96d1fc98b28fdaf9f0772aa"
 
-lodash.restparam@*, lodash.restparam@^3.0.0:
+lodash.restparam@^3.0.0:
   version "3.6.1"
   resolved "https://registry.yarnpkg.com/lodash.restparam/-/lodash.restparam-3.6.1.tgz#936a4e309ef330a7645ed4145986c85ae5b20805"
 
@@ -3479,6 +3469,13 @@ minimatch@1:
   dependencies:
     brace-expansion "^1.0.0"
 
+minimatch@~0.2.11:
+  version "0.2.14"
+  resolved "https://registry.yarnpkg.com/minimatch/-/minimatch-0.2.14.tgz#c74e780574f63c6f9a090e90efbe6ef53a6a756a"
+  dependencies:
+    lru-cache "2"
+    sigmund "~1.0.0"
+
 minimist@0.0.8, minimist@~0.0.1:
   version "0.0.8"
   resolved "https://registry.yarnpkg.com/minimist/-/minimist-0.0.8.tgz#857fcabfc3397d2625b8228262e86aa7a011b05d"
@@ -3497,20 +3494,19 @@ mkdirp@0.5.1, mkdirp@0.5.x, "mkdirp@>=0.5 0", mkdirp@^0.5.0, mkdirp@^0.5.1, mkdi
   dependencies:
     minimist "0.0.8"
 
-mocha@^2.4.5:
-  version "2.5.3"
-  resolved "https://registry.yarnpkg.com/mocha/-/mocha-2.5.3.tgz#161be5bdeb496771eb9b35745050b622b5aefc58"
+mocha@2.4.5:
+  version "2.4.5"
+  resolved "https://registry.yarnpkg.com/mocha/-/mocha-2.4.5.tgz#151768dd2875eb51bc8295e9800026e9f2bb398f"
   dependencies:
     commander "2.3.0"
     debug "2.2.0"
     diff "1.4.0"
     escape-string-regexp "1.0.2"
-    glob "3.2.11"
-    growl "1.9.2"
+    glob "3.2.3"
+    growl "1.8.1"
     jade "0.26.3"
     mkdirp "0.5.1"
     supports-color "1.2.0"
-    to-iso-string "0.0.2"
 
 modify-babel-preset@^2.1.1:
   version "2.1.1"
@@ -4407,7 +4403,7 @@ readable-stream@~2.1.2, readable-stream@~2.1.4, readable-stream@~2.1.5:
     string_decoder "~0.10.x"
     util-deprecate "~1.0.1"
 
-readdir-scoped-modules@*, readdir-scoped-modules@^1.0.0:
+readdir-scoped-modules@^1.0.0:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/readdir-scoped-modules/-/readdir-scoped-modules-1.0.2.tgz#9fafa37d286be5d92cbaebdee030dc9b5f406747"
   dependencies:
@@ -4501,17 +4497,18 @@ repeating@^2.0.0:
   dependencies:
     is-finite "^1.0.0"
 
-request@2, request@^2.47.0, request@^2.49.0, request@^2.55.0, request@^2.74.0, request@^2.79.0:
-  version "2.79.0"
-  resolved "https://registry.yarnpkg.com/request/-/request-2.79.0.tgz#4dfe5bf6be8b8cdc37fcf93e04b65577722710de"
+request@2, request@2.72.0, request@^2.47.0, request@^2.49.0, request@^2.55.0, request@~2.72.0:
+  version "2.72.0"
+  resolved "https://registry.yarnpkg.com/request/-/request-2.72.0.tgz#0ce3a179512620b10441f14c82e21c12c0ddb4e1"
   dependencies:
     aws-sign2 "~0.6.0"
     aws4 "^1.2.1"
+    bl "~1.1.2"
     caseless "~0.11.0"
     combined-stream "~1.0.5"
     extend "~3.0.0"
     forever-agent "~0.6.1"
-    form-data "~2.1.1"
+    form-data "~1.0.0-rc3"
     har-validator "~2.0.6"
     hawk "~3.1.3"
     http-signature "~1.1.0"
@@ -4519,25 +4516,24 @@ request@2, request@^2.47.0, request@^2.49.0, request@^2.55.0, request@^2.74.0, r
     isstream "~0.1.2"
     json-stringify-safe "~5.0.1"
     mime-types "~2.1.7"
+    node-uuid "~1.4.7"
     oauth-sign "~0.8.1"
-    qs "~6.3.0"
+    qs "~6.1.0"
     stringstream "~0.0.4"
-    tough-cookie "~2.3.0"
+    tough-cookie "~2.2.0"
     tunnel-agent "~0.4.1"
-    uuid "^3.0.0"
 
-request@2.72.0, request@~2.72.0:
-  version "2.72.0"
-  resolved "https://registry.yarnpkg.com/request/-/request-2.72.0.tgz#0ce3a179512620b10441f14c82e21c12c0ddb4e1"
+request@^2.74.0, request@^2.79.0:
+  version "2.79.0"
+  resolved "https://registry.yarnpkg.com/request/-/request-2.79.0.tgz#4dfe5bf6be8b8cdc37fcf93e04b65577722710de"
   dependencies:
     aws-sign2 "~0.6.0"
     aws4 "^1.2.1"
-    bl "~1.1.2"
     caseless "~0.11.0"
     combined-stream "~1.0.5"
     extend "~3.0.0"
     forever-agent "~0.6.1"
-    form-data "~1.0.0-rc3"
+    form-data "~2.1.1"
     har-validator "~2.0.6"
     hawk "~3.1.3"
     http-signature "~1.1.0"
@@ -4545,12 +4541,12 @@ request@2.72.0, request@~2.72.0:
     isstream "~0.1.2"
     json-stringify-safe "~5.0.1"
     mime-types "~2.1.7"
-    node-uuid "~1.4.7"
     oauth-sign "~0.8.1"
-    qs "~6.1.0"
+    qs "~6.3.0"
     stringstream "~0.0.4"
-    tough-cookie "~2.2.0"
+    tough-cookie "~2.3.0"
     tunnel-agent "~0.4.1"
+    uuid "^3.0.0"
 
 request@~2.34.0:
   version "2.34.0"
@@ -4637,14 +4633,10 @@ resolve-from@^1.0.0:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/resolve-from/-/resolve-from-1.0.1.tgz#26cbfe935d1aeeeabb29bc3fe5aeb01e93d44226"
 
-resolve@1.1.7:
+resolve@1.1.7, resolve@^1.0.0, resolve@^1.1.6:
   version "1.1.7"
   resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.1.7.tgz#203114d82ad2c5ed9e8e0411b3932875e889e97b"
 
-resolve@^1.0.0, resolve@^1.1.6:
-  version "1.2.0"
-  resolved "https://registry.yarnpkg.com/resolve/-/resolve-1.2.0.tgz#9589c3f2f6149d1417a40becc1663db6ec6bc26c"
-
 restore-cursor@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/restore-cursor/-/restore-cursor-1.0.1.tgz#34661f46886327fed2991479152252df92daa541"
@@ -4750,11 +4742,7 @@ sax@^1.1.4:
   version "1.2.2"
   resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.2.tgz#fd8631a23bc7826bef5d871bdb87378c95647828"
 
-"semver@2 >=2.2.1 || 3.x || 4 || 5", "semver@2 || 3 || 4 || 5", "semver@2.x || 3.x || 4 || 5", "semver@4 || 5", "semver@^2.3.0 || 3.x || 4 || 5", semver@^5.3.0, semver@~5.3.0:
-  version "5.3.0"
-  resolved "https://registry.yarnpkg.com/semver/-/semver-5.3.0.tgz#9b2ce5d3de02d17c6012ad326aa6b4d0cf54f94f"
-
-semver@5.1.0, semver@~5.1.0:
+"semver@2 >=2.2.1 || 3.x || 4 || 5", "semver@2 || 3 || 4 || 5", "semver@2.x || 3.x || 4 || 5", "semver@4 || 5", semver@5.1.0, "semver@^2.3.0 || 3.x || 4 || 5", semver@~5.1.0:
   version "5.1.0"
   resolved "https://registry.yarnpkg.com/semver/-/semver-5.1.0.tgz#85f2cf8550465c4df000cf7d86f6b054106ab9e5"
 
@@ -4762,6 +4750,10 @@ semver@^4.1.0:
   version "4.3.6"
   resolved "https://registry.yarnpkg.com/semver/-/semver-4.3.6.tgz#300bc6e0e86374f7ba61068b5b1ecd57fc6532da"
 
+semver@^5.3.0, semver@~5.3.0:
+  version "5.3.0"
+  resolved "https://registry.yarnpkg.com/semver/-/semver-5.3.0.tgz#9b2ce5d3de02d17c6012ad326aa6b4d0cf54f94f"
+
 send@0.13.2:
   version "0.13.2"
   resolved "https://registry.yarnpkg.com/send/-/send-0.13.2.tgz#765e7607c8055452bba6f0b052595350986036de"
@@ -4951,7 +4943,7 @@ stringstream@~0.0.4:
   version "0.0.5"
   resolved "https://registry.yarnpkg.com/stringstream/-/stringstream-0.0.5.tgz#4e484cd4de5a0bbbee18e46307710a8a81621878"
 
-strip-ansi@*, strip-ansi@^3.0.0, strip-ansi@^3.0.1, strip-ansi@~3.0.1:
+strip-ansi@^3.0.0, strip-ansi@^3.0.1, strip-ansi@~3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/strip-ansi/-/strip-ansi-3.0.1.tgz#6a385fb8853d952d5ff05d0e8aaf94278dc63dcf"
   dependencies:
@@ -5076,10 +5068,6 @@ to-fast-properties@^1.0.1:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/to-fast-properties/-/to-fast-properties-1.0.2.tgz#f3f5c0c3ba7299a7ef99427e44633257ade43320"
 
-to-iso-string@0.0.2:
-  version "0.0.2"
-  resolved "https://registry.yarnpkg.com/to-iso-string/-/to-iso-string-0.0.2.tgz#4dc19e664dfccbe25bd8db508b00c6da158255d1"
-
 tough-cookie@>=0.12.0, tough-cookie@^2.2.0, tough-cookie@~2.3.0:
   version "2.3.2"
   resolved "https://registry.yarnpkg.com/tough-cookie/-/tough-cookie-2.3.2.tgz#f081f76e4c85720e6c37a5faced737150d84072a"
@@ -5208,7 +5196,7 @@ v8flags@^2.0.10:
   dependencies:
     user-home "^1.1.1"
 
-validate-npm-package-license@*, validate-npm-package-license@^3.0.1, validate-npm-package-license@~3.0.1:
+validate-npm-package-license@^3.0.1, validate-npm-package-license@~3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/validate-npm-package-license/-/validate-npm-package-license-3.0.1.tgz#2804babe712ad3379459acfbe24746ab2c303fbc"
   dependencies: