TUI

[Alizter]

In this PR we add some more features to Dune's TUI.

dune build -w --display tui

Description

We start by vendoring Lwd (light-weight document) and Nottui. We build on the Notty TUI that we currently have by switching components over to Nottui. This allows visual components to react to user input more locally, as in button handlers exist for each component rather than in a global loop like before. Lwd allows us to keep a persistent document state and allows components to be rerendered reactively to any changes.

This work builds on top of #7484.

Checklists

Doc:

• changelog
• (CLI) Documentation

Issues:

• Sometimes we might get a crash which will cause OCaml to complain about resouce deadlocks with the mutex. It happens occasionally with dune build and is reproducible when using dune monitor and connecting to a build with a diagnostic.
• In the above kind of crash, the terminal gets borked and requires a reset. We should work out how to recover.
• When we crash on startup, we don't print anything. Although, we do output to the log. (at least for dune build)

Visual issues:

• Terminals that don't have unicode don't look good. Not much we can do about this.
• When minimizing a message and getting a synopsis, the outline decorations might be over approximated. It's hard to do better than a rough approximation here at the moment.
• We cannot copy text. We should work out a way to allow the user to select and highlight text. (or even just add a copy button but thats a bit trickier).
• Make sure colours look good on light and dark terminals. See below.

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Demo

Click me

When running Dune (in watch mode) with --display tui the user will now be presented with the following screen.

The ? button in the top left corner opens the help screen. Clicking this opens the help screen which looks like this:

Next we purposefully create some errors in our build so we can see what messages look like:

As you can see, scroll bars appear in the TUI which can be interacted with using the mouse. You can also use the arrow keys or vim bindings to scroll and move around.

Above each message there is a horizontal rule, which shows 3 pieces of information.

1. Whether the message can be minimized or expanded. (currently it looks to be expandable).
2. What the ordinal of this message is.
3. The total number of messages.

We now click on the first message bar in order to demonstrate the minimization feature:

A short synopsis of the message is included and the rest of the message is hidden from view. We can see what this looks like as more error messages accumulate:

We can press m to minimize or expand all the messages at once, allowing the user to pick and choose which messages they want to see:

Here is a video demonstrating these behaviours:

Screencast.from.2023-08-21.19-20-44.webm

Appearance on white background

The white background doesn't look to great. It might be impossible to please everybody with this choice, so perhaps a better route would be to make these colours customizable from dune config.

[Alizter]

@rgrinberg I've moved drawing related things into a Drawing module and fixed the odoc comments.

[rgrinberg]

I removed the fist commit because it still needs some work. In particular, Report_error needs to check if the log is set before logging.

[rgrinberg]

This is good enough for now. Thanks.