Allowing reserved characters in a path variables makes '+' decode as a space

[Iman78]

Expected Behavior

To support '+' in the path portion of the url, I'm using https://www.rfc-editor.org/rfc/rfc6570#section-3.2.3 to allow reserved characters like so:

  @Get("{+variable}")
  public HttpResponse<Object> method(@PathVariable("variable") String variable) {
      ...
  }

From this test I understand that f I call my GET endpoint with /tes+t, I should expect the value of variable to be tes+t.

Actual Behaviour

Instead I get tes t. The plus sign is decoded as a space, which seems to be due to the use of java.net.URLDecoder in DefaultUriRouteMatch.
If you think this behavior should remain, then it'd be very helpful to have a configuration to opt-out of it.

Steps To Reproduce

1. Any project with an http server.
2. Add an endpoint that has a path variable allowing reserved characters: @Get("{+variable}")
3. Send a request to said endpoint with a value containing the plus sign.
4. Inspect the value of the variable inside to annotated method, it should have a space instead of the plus sign.

Environment Information

OS: MacOS Catalina
JDK 11

Example Application

No response

Version

3.6.0

[ojebari-ma]

Can you please confirm that this is still an issue in the latest version of Micronaut?