test: add coverage for invalid URLs

tests/test_scope.js

@@ -47,6 +47,26 @@ describe('`Scope#constructor`', () => {
     expect(() => nock('localhost/foo')).to.throw()
     expect(() => nock('foo.com:1234')).to.throw()
   })
+
+  it('throws on invalid URL format', async () => {
+    expect(() => nock(['This is not a url'])).to.throw()
+    // The following contains all valid properties of WHATWG URL, but is not an instance of URL.
+    // Maybe we should support object literals some day? A simple duck-type validator would suffice.
+    expect(() => nock({
+      href: 'http://google.com/foo',
+      origin: 'http://google.com',
+      protocol: 'http:',
+      username: '',
+      password: '',
+      host: 'google.com',
+      hostname: 'google.com',
+      port: 80,
+      pathname: '/foo',
+      search: '',
+      searchParams: {},
+      hash: '',
+    })).to.throw()
+  })
 })
 
 describe('`Scope#remove()`', () => {