diff --git a/src/header/interpreter.ts b/src/header/interpreter.ts
index 423698d..e653a04 100644
--- a/src/header/interpreter.ts
+++ b/src/header/interpreter.ts
@@ -35,8 +35,6 @@ export const defaultHeaderInterpreter: HeadersInterpreter = (headers) => {
 
       return (maxAge - Number(age)) * 1000;
     }
-
-    return undefined;
   }
 
   const expires = headers[Header.Expires];
diff --git a/test/interceptors/util.test.ts b/test/interceptors/util.test.ts
index 6089d66..cedc1df 100644
--- a/test/interceptors/util.test.ts
+++ b/test/interceptors/util.test.ts
@@ -1,4 +1,4 @@
-import { createValidateStatus } from '../../src/interceptors/util';
+import { createValidateStatus, isMethodIn } from '../../src/interceptors/util';
 
 describe('test util functions', () => {
   it('tests validate-status function', async () => {
@@ -19,4 +19,15 @@ describe('test util functions', () => {
     expect(randomValue(405)).toBe(true);
     expect(randomValue(304)).toBe(true);
   });
+
+  it('tests isMethodIn function', () => {
+    expect(isMethodIn('get', ['get', 'post'])).toBe(true);
+    expect(isMethodIn('get', ['get', 'post', 'put'])).toBe(true);
+    expect(isMethodIn('post', ['get', 'post', 'put'])).toBe(true);
+
+    expect(isMethodIn('get')).toBe(false);
+    expect(isMethodIn('get', [])).toBe(false);
+    expect(isMethodIn('post', ['get', 'put', 'delete'])).toBe(false);
+    expect(isMethodIn('get', ['post', 'put', 'delete'])).toBe(false);
+  });
 });