OSC sequences are malformed in a prompt

[cpendery]

What happened, and what did you expect to happen?

Similar to #1836, I need to emit non-standard sequences in the prompt for microsoft/inshellisense#138. When trying to emit some OSC sequences prefixing the prompt as shown below, I get the following output in my terminal. It would be great if OSC sequences could be passed through directly to the terminal instead of being parsed / modified as shown below

command

var user_prompt = $edit:prompt
fn prompt {
    put "\x1b]6973;PS\x07"
    $user_prompt
}
set edit:prompt = { prompt }

resulting prompt

^[]6973;PS^G~\OneDrive - Microsoft\Documents\code\clac>

Output of "elvish -version"

0.21.0+official

Code of Conduct

• I agree to follow Elvish's Code of Conduct.

[MrOverlord]

For what it is worth, I think you can basically achieve the desired effect via the edit:before-readline hook. In my case (emitting escape sequences to enable jumping between prompts in the Foot terminal emulator) the following works, while injecting them into the prompt led to junk being printed:

set edit:before-readline = [$@edit:before-readline { printf "\e]133;A\e\\" } ]

[cpendery]

I need to track multiple points of the prompt (points a-d as show below) which I don't think I can achieve with the hooks. These hook look great for reporting other information though (cwd, last command's status, etc).

aprompt>b                                                                                             c[right-prompt]d