Windows Terminal hangs up and disappears on window resizing.

[Hamayama]

Environment

Windows build number: 10.0.19042.0
Windows Terminal version (if applicable): 1.6.10571.0

Any other software?

vim 8.2

Steps to reproduce

1. vim aiueo.txt

   ( aiueo.txt is text file including wide characters. )

2. Narrowing the window width by mouse.

Expected behavior

The window is resized normally.

Actual behavior

Windows Terminal hangs up (few seconds) and disappears.

( the condition seems to be a line wrapping of wide characters. )

[Hamayama]

[zadjii-msft]

Well, this could be any of:

• Windows Terminal (Preview) crashes with wrapped text #8730
• Windows Terminal Crashed on window resizing. #8596
• Windows Terminal crashing when resizing panes #8287
• Crash in Windows Terminal TerminalControl!TextBuffer::Reflow #4907

Could you send us a Feedback Hub trace of the crash, to help identify the root cause?

/feedback

[ghost]

Hi there!

Can you please send us feedback with the Feedback Hub with this issue and paste the link here so we can more easily find your crash information on the back end?

Thanks!

[Hamayama]

I sent feedback.

https://aka.ms/AAbm3go

[zadjii-msft]

@DHowett Is there anyone on the team that can actually still access feedback hub links? Or are we all locked out now 😑

[DHowett]

If I had to simply guess, this is the PrepareForDoubleByteSequence resize crash we know about. @zadjii-msft hit me up on Teams -- there's a way 😄

[zadjii-msft]

 "providerName": "Microsoft.Windows.Terminal.Control",
 "lineNumber": "286",
 "fileName": "E:\\BA\\3\\s\\src\\buffer\\out\\textBuffer.cpp",
 "hresult": "2147549183",

Yep, it was _PrepareForDoubleByteSequence, which is #7417, which is #4907

/dup #4907

[ghost]

Hi! We've identified this issue as a duplicate of another one that already exists on this Issue Tracker. This specific instance is being closed in favor of tracking the concern over on the referenced thread. Thanks for your report!

[Hamayama]

I understood this issue is a duplicate of #4907.
But, I will try to investigate a little by myself.

• type aiueo_unicode.txt → resize → no problem

• vim aiueo_unicode.txt → resize → problem occurs

So, there might be a display conflict with vim and windows terminal.

--
file: aiueo_unicode.txt

[Hamayama]

I set up VS2019 and checked the call stack.

• vim aiueo_unicode.txt → resize

src/buffer/out/textBuffer.cpp
  TextBuffer::Reflow
      ↓
  newBuffer.InsertCharacter
      ↓
  _PrepareForDoubleByteSequence
      ↓
  _AssertValidDoubleByteSequence
    // N, T failing case (uncorrectable) or
    // L, N and L, L failing cases (correctable) or
    // T, T failing case (uncorrectable)
    return false;
      ↓
  _PrepareForDoubleByteSequence
    FAIL_FAST_IF → Unhandled exception

[Hamayama]

I made a quick fix.

diff -u -r src_orig/buffer/out/textBuffer.cpp src/buffer/out/textBuffer.cpp
--- src_orig/buffer/out/textBuffer.cpp	2021-04-11 20:24:10.253074800 +0900
+++ src/buffer/out/textBuffer.cpp	2021-04-12 22:05:31.059636600 +0900
@@ -2192,6 +2192,12 @@
                 const auto dbcsAttr = row.GetCharRow().DbcsAttrAt(iOldCol);
                 const auto textAttr = row.GetAttrRow().GetAttrByColumn(iOldCol);
 
+                // workaround for https://github.com/microsoft/terminal/issues/9547
+                if (!newBuffer._AssertValidDoubleByteSequence(dbcsAttr))
+                {
+                    break;
+                }
+
                 if (!newBuffer.InsertCharacter(glyph, dbcsAttr, textAttr))
                 {
                     hr = E_OUTOFMEMORY;

There seems to be multiple error handling methods.

1. hr = E_OUTOFMEMORY; break;
2. CATCH_RETURN();
3. FAIL_FAST_IF();

But, no method seems to be useful for this issue ...

[DHowett]

Sorry -- we actually have a fix for this one coming back in from the Windows OS code. I haven't merged it into this repository yet!

[DHowett]

Thanks for the reminder, though -- i need to do that before we ship 1.7 (!)