diff --git a/package-lock.json b/package-lock.json
index 5894d7c..9678a24 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -93,6 +93,12 @@
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@@ -558,6 +584,15 @@
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@@ -582,6 +617,15 @@
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@@ -602,6 +646,12 @@
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@@ -766,6 +816,12 @@
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@@ -858,6 +914,12 @@
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-          "dev": true
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-          "resolved": "https://registry.npmjs.org/growl/-/growl-1.10.3.tgz",
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@@ -2160,6 +2195,12 @@
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+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.0.tgz",
+      "integrity": "sha1-uULm1L3mUwBe9rcTYd74cn0GReA=",
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@@ -2734,6 +2775,12 @@
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+      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.6.tgz",
+      "integrity": "sha512-qZ3bAurt2IXGPR3c57PyaSYEnQiLRwPeS60G9TahElBZsdOABo+iKYch/PhRjSTZJ5/DF08x43XMt9qec2g3ig==",
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diff --git a/package.json b/package.json
index c6251ec..eabd916 100644
--- a/package.json
+++ b/package.json
@@ -47,7 +47,7 @@
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-    "chai": "3.5.0",
+    "chai": "4.1.2",
     "grunt": "1.0.2",
     "grunt-contrib-jshint": "1.1.0",
     "grunt-contrib-watch": "1.0.0",