diff --git a/test/author_test.js b/test/author_test.js
index 807e219d..62148ea0 100644
--- a/test/author_test.js
+++ b/test/author_test.js
@@ -31,7 +31,7 @@ describe('Author', () => {
       });
 
       expect(author.email).to.equal('cedric@belin.io');
-      expect(author.url.href).to.equal('https://belin.io/');
+      expect(author.url).to.be.instanceOf(URL).and.have.property('href').that.equal('https://belin.io/');
     });
   });
 
diff --git a/test/blog_test.js b/test/blog_test.js
index db78cb3c..8aefca09 100644
--- a/test/blog_test.js
+++ b/test/blog_test.js
@@ -36,7 +36,7 @@ describe('Blog', () => {
       expect(blog.languages).to.be.an('array').and.have.lengthOf(2);
       expect(blog.languages[0]).to.equal('en');
       expect(blog.languages[1]).to.equal('fr');
-      expect(blog.url.href).to.equal('https://github.com/cedx/akismet.js');
+      expect(blog.url).to.be.instanceOf(URL).and.have.property('href').that.equal('https://github.com/cedx/akismet.js');
     });
   });
 
diff --git a/test/client_test.js b/test/client_test.js
index 2f45c73c..cabd31d3 100644
--- a/test/client_test.js
+++ b/test/client_test.js
@@ -72,7 +72,7 @@ describe('Client', function() {
       let data = client.toJSON();
       expect(data.apiKey).to.equal('0123456789-ABCDEF');
       expect(data.blog).to.be.null;
-      expect(data.endPoint.href).to.equal('http://localhost/');
+      expect(data.endPoint).to.be.instanceOf(URL).and.have.property('href').that.equal('http://localhost/');
       expect(data.isTest).to.be.false;
       expect(data.userAgent).to.equal('FooBar/6.6.6');
     });
@@ -82,7 +82,7 @@ describe('Client', function() {
       expect(Object.keys(data)).to.have.lengthOf(5);
       expect(data.apiKey).to.equal(process.env.AKISMET_API_KEY);
       expect(data.blog).to.equal('Blog');
-      expect(data.endPoint.href).to.equal(Client.DEFAULT_ENDPOINT.href);
+      expect(data.endPoint).to.be.instanceOf(URL).and.have.property('href').that.equal(Client.DEFAULT_ENDPOINT.href);
       expect(data.isTest).to.be.true;
       expect(data.userAgent.startsWith('Node.js/')).to.be.true;
     });
diff --git a/test/comment_test.js b/test/comment_test.js
index d4dba3d8..9ae4e823 100644
--- a/test/comment_test.js
+++ b/test/comment_test.js
@@ -41,7 +41,7 @@ describe('Comment', () => {
       expect(comment.content).to.equal('A user comment.');
       expect(comment.date).to.be.instanceof(Date);
       expect(comment.date.getFullYear()).to.equal(2000);
-      expect(comment.referrer.href).to.equal('https://belin.io/');
+      expect(comment.referrer).to.be.instanceOf(URL).and.have.property('href').that.equal('https://belin.io/');
       expect(comment.type).to.equal(CommentType.TRACKBACK);
     });
   });