Test: Integrated terminal IME support

[Tyriar]

Test for #7045:

• Windows - @rebornix
• OS X - @kieferrm
• Linux - @joaomoreno

The integrated terminal now supports input via IMEs (Input Method Editors). During development I tested this across all 3 OS' with Japanese and Korean IMEs as I'm familiar with them. Here are some things to try:

• Install/enable an IME for the OS, preferably not Japanese/Korean
• Test input, if you're familiar with the IME try all the edge cases
  • Multiple character compositions?
  • Multiple keystrokes per character?
  • Multiple characters reducing to a single character?
• Test executing a command using the text (eg. echo)

See xtermjs/xterm.js#175 for more details on the change and testing that was performed at implementation time.

[ZCShou]

@Tyriar Cannot follow cursor! The first input is ok ,but The following Input can not work well!

Win10 x64 Chinese IME

[rebornix]

@Tyriar try type two Chinese characters then switch to English and type 'abc', you will see the cursor position is wrong, which breaks deleting functionality.

[Tyriar]

@ZCShou @rebornix are you experiencing the cursor-related issue I describe at the bottom of xtermjs/xterm.js#175 (comment)? I found that input seemed fine but the cursor disappeared so the composition window was never in the right position.

[rebornix]

@Tyriar I ran into the issue you described there and the input works fine. Besides, the cursor position comes back if you switch to English IME but the position is wrong, and its offset depends on how many Chinese characters you type

At first, type abc and the cursor is at the right of last char.

Then type a Chinese char 吕 (lv) and abc again

See above, the cursor is on last char. Then you type 鹏 (peng) and abc

The cursor now is on the last two char of text. I suppose its offset is just how many Chinese chars you type. My suspicion is we don't move the cursor position when we handle CJK IME composition?

[Tyriar]

The cursor position is handled entirely by the pty though, not vscode. I wonder if this is something to do with #7345 which is an upstream problem that does weird things when using backspace/left/right.

[joaomoreno]

@Tyriar I've found it hard to test and even to know whether what I did actually tested your work. I followed a guide or two in installing IMEs, I was able to type some Japanese/Korean, but I'm not sure I actually tested what you should be tested.

[Tyriar]

@joaomoreno no problems, I did a bunch of testing myself on Linux so hopefully that will be enough.