Strange problems with 'less' program on Linux/macOS

I have an Atom plugin named ‘atom-xterm’ which provides terminal emulators in the editor. On Linux and macOS, the less program acts strange. Upon initially starting up less (for example less --help), part of the top portion of the help doc that is displayed is cut off. Also the bottom portion leaves a bunch of blank lines. Also, when you move up or down, you can see portions in the middle of the doc get cut off. Upon quiting and running less again however, less works fine. This happens whenever a new terminal is started or a terminal is resized. Below is a gif on my Ubuntu VM showing exactly what I mean.

This happens consistently on any Linux (at least Ubuntu) or macOS machine. Other terminal emulator program of course don’t have this problem. Also, the ‘less’ program available through Git for Windows works fine.

Details

• Browser and browser version: This is actually happening in the Atom editor. Here are the details atom --version. Atom : 1.19.7 Electron: 1.6.9 Chrome : 56.0.2924.87 Node : 7.4.0

• OS version: Details from lsb_release -a Distributor ID: Ubuntu Description: Ubuntu 17.04 Release: 17.04 Codename: zesty

• xterm.js version: v2.9.2

Steps to reproduce

1. In the latest Atom editor with the latest atom-xterm plugin, on Linux or macOS, start less --help.
2. Start moving around the displayed doc to see the issue.
3. Close less, then reopen.
4. Find that less now almost displays correctly save for the top line which still shows the output from the current shell.

[gtritchie]

Lack of time. I will do it in our next major release, but getting late in the cycle for the release that’s in flight. We’re a desktop product and a purely web product (desktop is a Qt frame using Chromium via QtWebEngine), and our JavaScript is mostly generated from Java via Gwt. Translation: things that should seem trivial sometimes aren’t.

I did a brief experiment when 3.0 came out and hit two things (which I haven’t revisited yet):

• theming; we did it via .css files generated by our build, so I need to do some work there to adapt to the new-improved model
• require.js: our code barfed on that; we have other dependencies, some quite old, which impose constraints there; I see there was some work on that in subsequent 3.x, so maybe that’s already solved for me

Anyway, thanks for the great work!

[Tyriar]

@gtritchie ah yes there were some hiccups regarding require.js, I’m hoping they’re resolved now.