diff --git a/package.json b/package.json
index cff9796..01c4ebe 100644
--- a/package.json
+++ b/package.json
@@ -12,7 +12,7 @@
     "lint": "eslint --ext js,jsx ."
   },
   "devDependencies": {
-    "chai": "^4.1.2",
+    "chai": "^4.3.4",
     "eslint": "^3.0.0",
     "eslint-config-standard": "^10.2.1",
     "eslint-config-vue": "^2.0.2",
diff --git a/yarn.lock b/yarn.lock
index e22f378..6bef69c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -220,9 +220,9 @@ assert@^1.1.1:
   dependencies:
     util "0.10.3"
 
-assertion-error@^1.0.1:
-  version "1.0.2"
-  resolved "https://registry.yarnpkg.com/assertion-error/-/assertion-error-1.0.2.tgz#13ca515d86206da0bac66e834dd397d87581094c"
+assertion-error@^1.1.0:
+  version "1.1.0"
+  resolved "https://registry.yarnpkg.com/assertion-error/-/assertion-error-1.1.0.tgz#e60b6b0e8f301bd97e5375215bda406c85118c0b"
 
 async-each@^1.0.0:
   version "1.0.1"
@@ -1101,16 +1101,16 @@ center-align@^0.1.1:
     align-text "^0.1.3"
     lazy-cache "^1.0.3"
 
-chai@^4.1.2:
-  version "4.1.2"
-  resolved "https://registry.yarnpkg.com/chai/-/chai-4.1.2.tgz#0f64584ba642f0f2ace2806279f4f06ca23ad73c"
+chai@^4.3.4:
+  version "4.3.4"
+  resolved "https://registry.yarnpkg.com/chai/-/chai-4.3.4.tgz#b55e655b31e1eac7099be4c08c21964fce2e6c49"
   dependencies:
-    assertion-error "^1.0.1"
-    check-error "^1.0.1"
-    deep-eql "^3.0.0"
+    assertion-error "^1.1.0"
+    check-error "^1.0.2"
+    deep-eql "^3.0.1"
     get-func-name "^2.0.0"
-    pathval "^1.0.0"
-    type-detect "^4.0.0"
+    pathval "^1.1.1"
+    type-detect "^4.0.5"
 
 chalk@^1.0.0, chalk@^1.1.1, chalk@^1.1.3:
   version "1.1.3"
@@ -1130,7 +1130,7 @@ chalk@^2.0.1, chalk@^2.1.0:
     escape-string-regexp "^1.0.5"
     supports-color "^4.0.0"
 
-check-error@^1.0.1:
+check-error@^1.0.2:
   version "1.0.2"
   resolved "https://registry.yarnpkg.com/check-error/-/check-error-1.0.2.tgz#574d312edd88bb5dd8912e9286dd6c0aed4aac82"
 
@@ -1627,7 +1627,7 @@ decamelize@^1.0.0, decamelize@^1.1.1, decamelize@^1.1.2:
   version "1.2.0"
   resolved "https://registry.yarnpkg.com/decamelize/-/decamelize-1.2.0.tgz#f6534d15148269b20352e7bee26f501f9a191290"
 
-deep-eql@^3.0.0:
+deep-eql@^3.0.1:
   version "3.0.1"
   resolved "https://registry.yarnpkg.com/deep-eql/-/deep-eql-3.0.1.tgz#dfc9404400ad1c8fe023e7da1df1c147c4b444df"
   dependencies:
@@ -4195,9 +4195,9 @@ path-type@^2.0.0:
   dependencies:
     pify "^2.0.0"
 
-pathval@^1.0.0:
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/pathval/-/pathval-1.1.0.tgz#b942e6d4bde653005ef6b71361def8727d0645e0"
+pathval@^1.1.1:
+  version "1.1.1"
+  resolved "https://registry.yarnpkg.com/pathval/-/pathval-1.1.1.tgz#8534e77a77ce7ac5a2512ea21e0fdb8fcf6c3d8d"
 
 pbkdf2@^3.0.3:
   version "3.0.13"
@@ -5674,9 +5674,9 @@ type-check@~0.3.2:
   dependencies:
     prelude-ls "~1.1.2"
 
-type-detect@^4.0.0:
-  version "4.0.3"
-  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-4.0.3.tgz#0e3f2670b44099b0b46c284d136a7ef49c74c2ea"
+type-detect@^4.0.0, type-detect@^4.0.5:
+  version "4.0.8"
+  resolved "https://registry.yarnpkg.com/type-detect/-/type-detect-4.0.8.tgz#7646fb5f18871cfbb7749e69bd39a6388eb7450c"
 
 type-is@~1.6.15:
   version "1.6.15"