This is a pure refactor in preparation for letting users configure multiple
alternate bindings for a single command. Every Binding still has exactly one
key, so nothing changes visibly: the cheatsheet, the on-screen options bar,
and the keybindings menu all render identically.
When a Binding ends up with multiple keys, the on-screen options bar will
show only the first (to avoid clutter); the cheatsheet will show all of them (in
a later commit). For now both paths take Key[0].
MenuItem.Key is changed in the same way, it also has a slice of keys now.
In this commit we keep the name `Key` in Binding, KeybindingOpts and MenuItem,
instead of renaming them to `Keys` right away, in order to keep the diff a bit
more readable. We'll do the rename separately in the next commit.
Modifiers were moved into Key in 22169e22f, but the separate Modifier field
on types.Binding and gocui.keybinding was left behind. The keypress matcher
already compares modifiers via Key.Equals, so the old field is never read on
the dispatch path; it just got passed through SetKeybinding and stored.
Drop it from gocui.keybinding, types.Binding, and the SetKeybinding /
DeleteKeybinding signatures, and remove every now-redundant Modifier:
gocui.ModNone struct field. Mouse bindings keep their own Modifier (on
ViewMouseBinding) since that path still consults it.
This bundles the keyName and a rune, so that we don't have to pass these around
separately everywhere. This should make it easier to swap out the rune for a
string when we upgrade to tcell v3.
I copied all files except dot files (.github and .gitignore), the _examples
folder, and go.mod/go.sum.
At some point we may want to copy the files back to the gocui repo when other
clients (e.g. lazydocker) want to use the newer versions of them.
We want to show an error when the user tries to invoke an action that expects only
a single item to be selected.
We're using the GetDisabledReason field to enforce this (as well as DisabledReason
on menu items).
I've created a ListControllerTrait to store some shared convenience functions for this.