feat(terminal)!: open :terminal in a split by default

[gpanders]

With a bang [!], :terminal opens a terminal buffer in the current window, discarding any changes to the current buffer unless 'hidden' is set (which it is by default as of #15410).

This is a BREAKING CHANGE.

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Note this reverts some of the changes from #15427 (notably the doc changes to |:horizontal| and the news.txt update from that PR).

[asmodeus812]

I find this defaulting to a split strange, given the fact you can prefix the term with mods for a split direction (i.e vert term and hor term), why then default to split. What is the point ?

[gpanders]

I find this defaulting to a split strange, given the fact you can prefix the term with mods for a split direction (i.e vert term and hor term),

Until 14 hours ago, no you could not.

Regardless, the point is that the more user friendly behavior should be the default. “Sane defaults” is one of the core philosophies and design drivers of the entire Neovim project. There are many issues with the current :term behavior of consuming the current window (I know, because I see the same questions being asked repeatedly).

There are valid use cases for the existing behavior, and for those :term! and termopen() are still available.

[asmodeus812]

Well In case it wasn't obvious, i was referring to exactly those changes.

Still, the question stands, i am not convinced by your argument at all, sane defaults is the cop out answer, as both are equally valid. I argue that term has no reason to split the current window by default. As it does more than what is expected imo.

[tssm]

I know I may lose this battle, but implicitly splitting windows has never been a sane default to me, the tab layout should be decided explicitly by the user IMO. Even :help is disruptive, and I had to script it a bit to stop opening a split. I guess it behaves the way it does because :hidden had to be set by the user, but that's not the case anymore, so having commands that behave different it's just annoying.

This is just a summary of what I said here. Again, I expect to lose this battle, but at least I tried 😅