[breaking batch] don't glob export ast::UnOp variants

[oli-obk]

r? @Manishearth

I just noticed they can't be rolled up (often modifying the same line(s) in imports). So once I reach the critical amount for them to be merged I'll create a PR that merges all of them.

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[Manishearth]

Feel free to just make a single PR which you keep adding commits to to avoid needing a rebase

[bluss]

Fyi the marker is exactly [breaking-change] with the hyphen. As used by http://bitrust.octarineparrot.com/.

[oli-obk]

ok, this is ready, I'm done for this run. Before the rebase + squash it passed locally. Let's see what travis says. The only potentially controversial changes are in libsyntax/ast.rs, everything else is just fallout due to the renamings or removal of glob exports.

[oli-obk]

jup travis likes it :)

[Manishearth]

Reviewed most of it, have marked places where I'm unsure of something.

[oli-obk]

addressed comments

[oli-obk]

the PR already bitrotted (see travis). rebasing...

[llogiq]

@petrochenkov I don't think it's too ugly, but I guess that's a matter of taste.

[petrochenkov]

Well, ok. I guess.
Also, @Manishearth when does the "breakage window" close? I wanted to do some refactoring is AST and to group it together with these changes to reduce breakage.

[Manishearth]

@petrochenkov In the past we didn't have a concrete policy on breakages.

Try to make a PR before this makes the nightly, basically. The window is flexible, though.

[Manishearth]

Also, if someone wants to do the same reexport change to the HIR it would be nice. Don't worry about breakages there, since only clippy and some other lints depend upon the HIR and we can take care of that.

[Manishearth]

now it has slipped through without much notice.

btw, regarding this, there wasn't much discussion on this PR, but people affected by breaking changes were pinged a couple of days ago on the older version of this PR (which was split up).

Usually I'd wait a few days so that further breaking changes can be collected; however this itself is a large collection of breakages and is large enough that it will bitrot almost every few hours.

In the future, if you feel the need to make a breaking change, make a PR, get reviewed (without the r+), and when we have enough of them around we can roll them up.

[llogiq]

@oli-obk perhaps you can say something about https://internals.rust-lang.org/t/nightly-broke-quote-tokens-1i32/3174/2 ?

[sgrif]

Is there some reasoning for this change? While I understand that we don't want libsyntax to be defacto stable, this seems like really unnecessary breakage that affects basically every crate doing anything with macros.

but people affected by breaking changes were pinged a couple of days ago on the older version of this PR (which was split up).

Nobody on the Diesel team was pinged. :\

[Manishearth]

@sgrif Ah, sorry. I didn't know that Diesel uses syntax extensions a lot. The main breakage I was worried about was serde/aster (which is used by half the ecosystem).

I'll ping y'all next time this happens, and keep a tracking issue where we can coordinate future libsyntax breaking changes.