diff --git a/package-lock.json b/package-lock.json
index 8bdda90d8..919821b9a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -2708,14 +2708,17 @@
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-      "resolved": "https://registry.npmjs.org/chai/-/chai-3.5.0.tgz",
-      "integrity": "sha1-TQJjewZ/6Vi9v906QOxW/vc3Mkc=",
+      "version": "4.3.4",
+      "resolved": "https://registry.npmjs.org/chai/-/chai-4.3.4.tgz",
+      "integrity": "sha512-yS5H68VYOCtN1cjfwumDSuzn/9c+yza4f3reKXlE5rUg7SFcCEy90gJvydNgOYtblyf4Zi6jIWRnXOgErta0KA==",
       "dev": true,
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-        "assertion-error": "^1.0.1",
-        "deep-eql": "^0.1.3",
-        "type-detect": "^1.0.0"
+        "assertion-error": "^1.1.0",
+        "check-error": "^1.0.2",
+        "deep-eql": "^3.0.1",
+        "get-func-name": "^2.0.0",
+        "pathval": "^1.1.1",
+        "type-detect": "^4.0.5"
       }
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@@ -2729,6 +2732,12 @@
         "supports-color": "^5.3.0"
       }
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+    "check-error": {
+      "version": "1.0.2",
+      "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.2.tgz",
+      "integrity": "sha1-V00xLt2Iu13YkS6Sht1sCu1KrII=",
+      "dev": true
+    },
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       "resolved": "https://registry.npmjs.org/chokidar/-/chokidar-1.7.0.tgz",
@@ -3640,20 +3649,12 @@
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-      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-0.1.3.tgz",
-      "integrity": "sha1-71WKyrjeJSBs1xOQbXTlaTDrafI=",
+      "version": "3.0.1",
+      "resolved": "https://registry.npmjs.org/deep-eql/-/deep-eql-3.0.1.tgz",
+      "integrity": "sha512-+QeIQyN5ZuO+3Uk5DYh6/1eKO0m0YmJFGNmFHGACpf1ClL1nmlV/p4gNgbl2pJGxgXb4faqo6UE+M5ACEMyVcw==",
       "dev": true,
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-      },
-      "dependencies": {
-        "type-detect": {
-          "version": "0.1.1",
-          "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-0.1.1.tgz",
-          "integrity": "sha1-C6XsKohWQORw6k6FBZcZANrFiCI=",
-          "dev": true
-        }
+        "type-detect": "^4.0.0"
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     "deep-is": {
@@ -6079,6 +6080,12 @@
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       "dev": true
     },
+    "get-func-name": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/get-func-name/-/get-func-name-2.0.0.tgz",
+      "integrity": "sha1-6td0q+5y4gQJQzoGY2YCPdaIekE=",
+      "dev": true
+    },
     "get-own-enumerable-property-symbols": {
       "version": "3.0.0",
       "resolved": "https://registry.npmjs.org/get-own-enumerable-property-symbols/-/get-own-enumerable-property-symbols-3.0.0.tgz",
@@ -9601,6 +9608,12 @@
         }
       }
     },
+    "pathval": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.1.tgz",
+      "integrity": "sha512-Dp6zGqpTdETdR63lehJYPeIOqpiNBNtc7BpWSLrOje7UaIsE5aY92r/AunQA7rsXvet3lrJ3JnZX29UPTKXyKQ==",
+      "dev": true
+    },
     "pbkdf2": {
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       "resolved": "https://registry.npmjs.org/pbkdf2/-/pbkdf2-3.0.17.tgz",
@@ -11582,9 +11595,9 @@
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     "type-detect": {
-      "version": "1.0.0",
-      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-1.0.0.tgz",
-      "integrity": "sha1-diIXzAbbJY7EiQihKY6LlRIejqI=",
+      "version": "4.0.8",
+      "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.8.tgz",
+      "integrity": "sha512-0fr/mIH1dlO+x7TlcMy+bIDqKPsw/70tVyeHW787goQjhmqaZe10uwLujubK9q9Lg6Fiho1KUKDYz0Z7k7g5/g==",
       "dev": true
     },
     "type-is": {
diff --git a/package.json b/package.json
index 5490bdf14..4bbc1468b 100644
--- a/package.json
+++ b/package.json
@@ -38,7 +38,7 @@
     "babelify": "^10.0.0",
     "browserify": "14.0.0",
     "browserify-istanbul": "2.0.0",
-    "chai": "3.5.0",
+    "chai": "4.3.4",
     "coveralls": "2.11.16",
     "cpy-cli": "^2.0.0",
     "dtslint": "^0.4.2",