[Mike Griese (zadjii-msft)]

When we resize the text buffer, initialize the buffer with the
_default_¹ attributes, not the current ones. If we use the current
attributes, then we can get into scenarios where something like vim is
running, and left the attributes set to something other than the
defaults, and when we resized the buffer, we'd fill it up with color, as
opposed to whatever the default would be.

This PR instead initializes the buffers with the default colors. It also
makes sure to set the active attributes of the newly created buffers
back to whatever the current attributes of the old buffer were.

[1]: For the Terminal, the default attributes are "default on default".
For conhost, the default attributes are whatever the result of
Settings::GetDefaultAttributes is, which could be any combo of the
legacy indices and the default color.

PR Checklist

• Closes Weird blue selection after closing neovim (WSL) #3848
• I work here
• Tests added/passed
• [n/a] Requires documentation to be updated

Validation Steps Performed

• ran tests

[Dustin L. Howett (MSFT) (DHowett-MSFT)]

I'm actually a bit worried about this -- considering that a resize "reveals new lines" below the prompt, those lines should be subject to the same attribute continuation rules... am I off base?

[Mike Griese (zadjii-msft)]

I honestly don't know. I'm not sure it's well defined behavior.

gnome-terminal definitely doesn't let you "reveal new lines" when you increase the height of the buffer - the buffer's always at the bottom, resizing just moves lines from scrollback into the buffer, so that's not really an issue for them.

IMO we should act like those lines don't exist until text gets to them. Then whenever text is output and we eventually do get to that line, we'll initialize it with whatever the new attributes should currently be for those lines. (IIRC, we already do that).

Maybe selfhost this (after 1.0) so we can see how it feels?

[Dustin L. Howett (DHowett)]

Okay. I'm a little scared, but this is probably correct. Resize should initialize to the default and then be filled up with the current attributes. Yes.

This isn't going to bother cmd's color command (in conhost), right?

[Dustin L. Howett (DHowett)]

whoa. this one scares me!! the session default attributes are more important in conhost than terminal. why the change?

[Dustin L. Howett (DHowett)]

oh but it defaults to {Default, Default} doesn't it

[Mike Griese (zadjii-msft)]

Oh I thought this was the way to do it post-#6506

[Dustin L. Howett (DHowett)]

ohhhhhhhhh okay

[Dustin L. Howett (DHowett)]

disc

[Dustin L. Howett (DHowett)]

@msftbot make sure Michael Niksa (@miniksa) signs

[Deleted user (ghost)]

Hello Dustin L. Howett (@DHowett)!

Because you've given me some instructions on how to help merge this pull request, I'll be modifying my merge approach. Here's how I understand your requirements for merging this pull request:

• I'll only merge this pull request if it's approved by Michael Niksa (@miniksa)

If this doesn't seem right to you, you can tell me to cancel these instructions and use the auto-merge policy that has been configured for this repository. Try telling me "forget everything I just told you".

[Michael Niksa (miniksa)]

Yeah. OK. It seems fair.

[Deleted user (ghost)]

🎉Windows Terminal Preview v1.9.1445.0 has been released which incorporates this pull request.:tada:

Handy links:

• Release Notes
• Store Download