diff --git a/test/helpers/font.js b/test/helpers/font.js
index fc1ee40..603037b 100644
--- a/test/helpers/font.js
+++ b/test/helpers/font.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/helpers/next-url.js b/test/helpers/next-url.js
index 87879c8..e1548b0 100644
--- a/test/helpers/next-url.js
+++ b/test/helpers/next-url.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/index.js b/test/index.js
index e6088b6..6c73ec2 100644
--- a/test/index.js
+++ b/test/index.js
@@ -1,5 +1,7 @@
 'use strict';
 
+require('chai').should();
+
 describe('NexT', () => {
   require('./helpers');
   require('./tags');
diff --git a/test/tags/button.js b/test/tags/button.js
index f74583a..2a3785a 100644
--- a/test/tags/button.js
+++ b/test/tags/button.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/caniuse.js b/test/tags/caniuse.js
index 1fe0e20..0a8e8ad 100644
--- a/test/tags/caniuse.js
+++ b/test/tags/caniuse.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/center-quote.js b/test/tags/center-quote.js
index 0f20488..2d52f2e 100644
--- a/test/tags/center-quote.js
+++ b/test/tags/center-quote.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/group-pictures.js b/test/tags/group-pictures.js
index fc242a6..0ca200c 100644
--- a/test/tags/group-pictures.js
+++ b/test/tags/group-pictures.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/label.js b/test/tags/label.js
index bf27108..c096f04 100644
--- a/test/tags/label.js
+++ b/test/tags/label.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/link-grid.js b/test/tags/link-grid.js
index 8faaf94..2d24f9f 100644
--- a/test/tags/link-grid.js
+++ b/test/tags/link-grid.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 
 const result = `<div class="link-grid"><div class="link-grid-container">
 <object class="link-grid-image" data="/images/sample.png"></object>
diff --git a/test/tags/mermaid.js b/test/tags/mermaid.js
index 47ca8e9..99ab879 100644
--- a/test/tags/mermaid.js
+++ b/test/tags/mermaid.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 
 const { escapeHTML } = require('hexo-util');
 
diff --git a/test/tags/note.js b/test/tags/note.js
index 6d11bca..dc12a79 100644
--- a/test/tags/note.js
+++ b/test/tags/note.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/pdf.js b/test/tags/pdf.js
index d360000..2a67991 100644
--- a/test/tags/pdf.js
+++ b/test/tags/pdf.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/tabs.js b/test/tags/tabs.js
index db09ab1..ae77fb9 100644
--- a/test/tags/tabs.js
+++ b/test/tags/tabs.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 const Hexo = require('hexo');
 const hexo = new Hexo();
 
diff --git a/test/tags/video.js b/test/tags/video.js
index fba2faf..ef811ea 100644
--- a/test/tags/video.js
+++ b/test/tags/video.js
@@ -1,6 +1,5 @@
 'use strict';
 
-require('chai').should();
 
 describe('video', () => {
   const postVideo = require('../../scripts/tags/video');
diff --git a/test/validate/index.js b/test/validate/index.js
index 15d736b..8381ae6 100644
--- a/test/validate/index.js
+++ b/test/validate/index.js
@@ -3,26 +3,25 @@
 const fs = require('fs');
 const path = require('path');
 const yaml = require('js-yaml');
-const should = require('chai').should();
 
 describe('Validate', () => {
   it('config', () => {
     const themeConfig = fs.readFileSync(path.join(__dirname, '../../_config.yml'));
-    should.not.throw(() => {
+    (() => {
       yaml.load(themeConfig);
-    });
+    }).should.not.throw();
   });
 
   it('vendors', () => {
     const vendorsFile = fs.readFileSync(path.join(__dirname, '../../_vendors.yml'));
-    should.not.throw(() => {
+    (() => {
       yaml.load(vendorsFile);
-    });
+    }).should.not.throw();
   });
 
   it('language', () => {
     const languagesPath = path.join(__dirname, '../../languages');
-    should.not.throw(() => {
+    (() => {
       fs.readdirSync(languagesPath).forEach(lang => {
         if (!lang.endsWith('.yml')) return;
         const languagePath = path.join(languagesPath, lang);
@@ -30,6 +29,6 @@ describe('Validate', () => {
           filename: path.relative(__dirname, languagePath)
         });
       });
-    });
+    }).should.not.throw();
   });
 });