Incorrect capital lettters on non-QWERTY layouts in VSCode when keyboardEnhancements is enabled #1623
Description
Describe the bug
In xterm.js (the terminal used in VSCode) with the keyboard enhancements enabled, keyPress events with the shift modifier receive the letter matching to the QWERTY layout.
Setup
- MacOS 26.3.1
- zsh 5.9, also reproduced on bash 3.2.57
- xterm.js (VSCode 1.111.0)
- no multiplexer
To Reproduce
- Create a bubble tea application, with keyboardEnhancements enabled
- Run it in the VSCode integrated terminal (xterm.js)
- In another layout than QWERTY, type a capital letter that does not match QWERTY ('A' in AZERTY for instance)
- Notice that the application considered it received the letter matching the QWERTY layout
Source Code
I ran the following snippet, that logs typed keys :
package main
import (
"fmt"
"log"
"os"
tea "charm.land/bubbletea/v2"
)
type Model struct {
}
func (m Model) Init() tea.Cmd {
return nil
}
func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
switch msg := msg.(type) {
case tea.KeyPressMsg:
log.Printf("input (key=%v) Text: %s", string(msg.Key().Code), msg.Text)
if msg.String() == "ctrl+c" {
return m, tea.Quit
}
}
return m, nil
}
func (m Model) View() tea.View {
v := tea.NewView("")
v.KeyboardEnhancements.ReportEventTypes = true
return v
}
func main() {
f, _ := os.OpenFile("output.log", os.O_RDWR|os.O_CREATE|os.O_APPEND, 0644)
log.SetOutput(f)
fmt.Println("listening to key events...")
m := Model{}
tea.NewProgram(m).Run()
fmt.Println("done")
}
Expected behavior
When typing 'A' on my azerty keyboard, I want a log that contains 'A'. Instead, the letter 'Q' is printed.
Screenshots
In this screengrab, we can see my sample program running in the VSCode integrated terminal. I first type using my AZERTY layout, then using the QWERTY layout. I edited ultraviolet to log all bytes received from the terminal as well.
Additional context
In AZERTY, the lowercase top left letter correctly sends the control sequence ^[97u (=> a) but with the shift modifier, it sends the control sequence ^[133;2u(=> Q)
If we want to receive the correct letter, we can enable the report alternate keys flag to the kitty keyboard configuration. With this modification, the control sequence becomes ^[133:65;2;3u which is then correctly interpreted as an A.
This is what is done in the helix text editor for instance and it works with non-QWERTY layouts. (here or here)