Lua scripts in Skink: init.lua commands and events

Write Lua in ~/.config/skink/init.lua (%APPDATA%\skink\init.lua on Windows). It runs when Skink starts.

skink.add_command("reviewed", function()
  skink.insert("// reviewed\n")
end)

skink.on("save", function(path)
  skink.message("saved " .. path)
end)

Restart Skink, then run :reviewed.

The API

Call	Does
`skink.add_command(name, fn)`	`:name ARGS` calls `fn(ARGS...)`
`skink.on(event, fn)`	`"open"`, `"save"` and `"change"` (after a typing pause) get the path. `"key"` gets an unbound key like `"Ctrl-Alt-J"`; return `true` to take it
`skink.text()` `skink.path()` `skink.lang()` `skink.selection()`	Read the file
`skink.cursor()` / `skink.set_cursor(line [, col])`	Cursor position, 1-based
`skink.insert(text)` / `skink.set_text(text)`	Type at the cursors / replace the whole text
`skink.action("Save")` / `skink.command("goto 10")`	Run any action or command
`skink.message(text)`	Show a message. `print()` shows a toast
`skink.set_status(name, text)`	An item on the right of the status line (`nil` removes it)
`skink.pick(title, items, fn)`	A list; `fn(label, index)` runs on `Enter`

All the edits of one call undo as one step.

Three complete examples are in docs/scripts: a word count in the status line, trim trailing spaces on save, and a TODO picker.

Lua 5.4 with table, string, math and utf8. No io or os: files and processes go through editor commands. No coroutines.
Each call may run for 250 ms, string patterns included, then it is stopped. All scripts share 32 MB.
Errors show as a toast; the editor keeps running.

A project can ship .skink/init.lua. Skink asks before running it:

This project has a script (.skink/init.lua) that can edit files and run commands. Run it? (t)rust / (n)o

It asks again whenever the file changes. Scripts that come with packages are asked about the same way, once per version.