URL with base is always used, even when absolute URL is provided

[phallguy]

MDN documentation for URL states that the base should only be used when url is a relative url. However the current implementation of URL (as of 0.60.4) in react-native always prepends the base if given.

React Native version:

System:
OS: macOS 10.14.6
CPU: (12) x64 Intel(R) Core(TM) i9-8950HK CPU @ 2.90GHz
Memory: 447.55 MB / 16.00 GB
Shell: 3.2.57 - /bin/bash
Binaries:
Node: 12.6.0 - /usr/local/bin/node
Yarn: 1.17.3 - /usr/local/bin/yarn
npm: 6.9.0 - /usr/local/bin/npm
Watchman: 4.9.0 - /usr/local/bin/watchman
SDKs:
iOS SDK:
Platforms: iOS 12.4, macOS 10.14, tvOS 12.4, watchOS 5.3
IDEs:
Android Studio: 3.4 AI-183.6156.11.34.5692245
Xcode: 10.3/10G8 - /usr/bin/xcodebuild
npmPackages:
react: ^16.9.0 => 16.9.0
react-native: 0.60.4 => 0.60.4
npmGlobalPackages:
react-native-cli: 2.0.1

Steps To Reproduce

const url = new URL("http://github.com", "http://google.com")
console.log(url.toString()) // => "http://google.comhttp://github.com"

Describe what you expected to happen:

const url = new URL("http://github.com", "http://google.com")
console.log(url.toString()) // => "http://github.com"

Snack, code example, screenshot, or link to a repository:

https://snack.expo.io/@phallguy/url-bug-report

Notice that if you view the snack with the "Web" preview, it is handled correctly.

[phallguy]

Related to #16434

[jeswinsimon]

Would this be a valid fix for this?

[phallguy]

Yes that looks like it would probably do the trick.

[jeswinsimon]

Ok. I will open a PR then.

[phallguy]

Unfortunately, I think the proposed change is going to break access to localhost. See #26019

[jeswinsimon]

Unfortunately, I think the proposed change is going to break access to localhost. See #26019

This is because the current validateBaseUrl expects a base url to be of the format domain-name.extension. I have proposed a fix in #26019.

[stale]

Hey there, it looks like there has been no activity on this issue recently. Has the issue been fixed, or does it still require the community's attention? This issue may be closed if no further activity occurs. You may also label this issue as a "Discussion" or add it to the "Backlog" and I will leave it open. Thank you for your contributions.

[stale]

Closing this issue after a prolonged period of inactivity. If this issue is still present in the latest release, please feel free to create a new issue with up-to-date information.