Route parameter value with an encoded '?' as %3F not decoded in params

[kellyrmilligan]

Version

4.1.1

Test Case

https://codesandbox.io/s/zqj6wvk7m3

Steps to reproduce

click on the Topic Example ?

Expected Behavior

topic example %3F should be displayed as topic example ?

Actual Behavior

the param is displayed as topic example %3F

[timdorr]

This is ultimately caused by history. Here's the issue open to track the bug: remix-run/history#505

[pshrmn]

As a follow up, history uses decodeURI to decode pathnames. decodeURI cannot decode escape sequences that could not have been created by encodeURI. This means that because encodeURI cannot encode a question mark, decodeURI cannot decode an encoded question mark.

const eU = encodeURI('?') // '?'
const eUC = encodeURIComponent('?') // '%3F'
decodeURI(eU) // '?'
decodeURI(eUC) // '%3F'

I would say that if you have characters that need to be encoded using encodeURIComponent, you should expect to have to call decodeURIComponent to decode them.