diff --git a/package.json b/package.json
index 500f8d815..f3b89ed37 100644
--- a/package.json
+++ b/package.json
@@ -10,7 +10,7 @@
     "unit": "mocha \"test/unit/**/*.ts\"",
     "integration": "mocha \"test/integration/**/*.ts\"",
     "e2e": "npm run build && mocha \"test/e2e/**/*.ts\"",
-    "test": "BUNDLES=cjs npm run build && mocha \"test/**/*.ts\"",
+    "test": "BUNDLES=cjs,umd npm run build && mocha \"test/**/*.ts\"",
     "benchmark": "ts-node benchmark",
     "coverage-html": "nyc --reporter=html mocha \"test/{unit,integration}/**/*.ts\"",
     "coverage-coveralls": "nyc mocha \"test/{unit,integration}/**/*.ts\" && nyc report --reporter=text-lcov | coveralls",
diff --git a/test/e2e/xhr.ts b/test/e2e/xhr.ts
index a29156ca9..3dcfe508a 100644
--- a/test/e2e/xhr.ts
+++ b/test/e2e/xhr.ts
@@ -130,13 +130,13 @@ describe('xhr', () => {
       server.respondWith('GET', 'https://example.com/views/foo.html',
         [200, { 'Content-Type': 'text/plain' }, 'foo1'])
       return engine.renderFile('foo.html')
-        .then((html) => {
+        .then((html: string) => {
           expect(html).to.equal('foo1')
           server.respondWith('GET', 'https://example.com/views/foo.html',
             [200, { 'Content-Type': 'text/plain' }, 'foo2'])
           return engine.renderFile('foo.html')
         })
-        .then(html => expect(html).to.equal('foo2'))
+        .then((html:string) => expect(html).to.equal('foo2'))
     })
     it('should respect cache=true option', () => {
       engine = new Liquid({
@@ -147,13 +147,13 @@ describe('xhr', () => {
       server.respondWith('GET', 'https://example.com/views/foo.html',
         [200, { 'Content-Type': 'text/plain' }, 'foo1'])
       return engine.renderFile('foo.html')
-        .then((html) => {
+        .then((html: string) => {
           expect(html).to.equal('foo1')
           server.respondWith('GET', 'https://example.com/views/foo.html',
             [200, { 'Content-Type': 'text/plain' }, 'foo2'])
           return engine.renderFile('foo.html')
         })
-        .then(html => expect(html).to.equal('foo1'))
+        .then((html:string) => expect(html).to.equal('foo1'))
     })
   })
 })